| 00:13 | Can you see me now? Nobody hear me. Nobody can see |
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| 00:25 | Can you hear me anybody? You you see the screen? And is |
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| 00:32 | , is it the presentation mode? , thank you. It's like pulling |
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| 00:39 | now. Pulling teeth is easier. ? A little bit on rock physics |
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| 00:46 | and we're gonna talk about the velocity an ideal media. Oh, we're |
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| 00:54 | have some exercises and I would prepare by mentioning that this is not going |
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| 01:01 | happen often. But the university every designates, designates so much money I |
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| 01:10 | back to the students. And this to take into effect the fact that |
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| 01:17 | , they had to pay for the building that athletics feel. Uh you |
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| 01:24 | , you had to pay that in tuition and fees. You realize |
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| 01:27 | don't you? What is it? a year? No, $100 a |
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| 01:32 | , something like that. Yeah, like that. $200 a year. |
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| 01:38 | so they're giving, giving me back you paid, you can, you |
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| 01:41 | uh have that back. But they said, Fred, I, I |
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| 01:46 | can't hand it back. So everybody expect that so could you kind of |
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| 01:50 | make it a, a reward? uh in other words, they won |
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| 01:55 | . And so I have to go and do this as a reward to |
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| 02:00 | one of you. So if I you beforehand and if you score well |
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| 02:05 | it, you potentially can earn a of dollars. That's my story. |
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| 02:12 | , I wanna believe in it. see. Ok? You heard |
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| 02:17 | didn't you people away from home? is a chance to earn some big |
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| 02:23 | . OK. It's like crypto It's crypto OK. Velocity of an |
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| 02:32 | medium purpose of the rock. different purposes. Uh Let me see |
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| 02:44 | I can't get that. Uh Relate physics importance to seismic amplitude review |
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| 02:55 | that control velocities in rock, examine these effects can be estimated this part |
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| 03:02 | the articles. You're right now, Wang's article, the three summary |
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| 03:06 | I really think you should kind of those again if you haven't read them |
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| 03:11 | this time after my lecture just concentrated little on it because it it's |
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| 03:16 | Uh even as a geologist looking at interpretation, you always wanna know, |
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| 03:20 | , how could that change? and knowing a little bit about the |
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| 03:25 | can tell you a lot, all have to ha have is uh see |
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| 03:29 | I had fractures. This is the this particular would look. So develop |
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| 03:36 | to predict velocity away from the But like it basically what we're here |
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| 03:42 | . I, I always tell the you're here for what the geologist ask |
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| 03:46 | what ifs. And so let's see we can't get, develop some answers |
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| 03:51 | those, what ifs because they're gonna them and they should, they're the |
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| 03:55 | that have to be able to portray back to the management. So there's |
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| 04:00 | many ways of doing this. We've field investigations in order to verify what's |
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| 04:06 | . Laboratory measurements, we have physical and laboratory, we have theory, |
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| 04:13 | malls and we borrow from other sister , rock mechanics, fluid form, |
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| 04:18 | et cetera. When I was in , I remember the chairman of our |
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| 04:26 | says no more damn physical models in lab. Whoa. And the reason |
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| 04:34 | he had one student that was studying and he would build, build a |
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| 04:41 | model. He would take a not . It's 44 gallon Farrell, put |
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| 04:49 | pipe in it, start filling it of concrete fracture, some of it |
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| 04:54 | more fracture, for more fracture fractures the borehole. Well, there's 1050 |
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| 05:01 | , 5044 barrel drums each weighing about and he just lets him sit there |
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| 05:09 | his degree and walks away. That one episode. The other one was |
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| 05:16 | one who studied physical modeling and he he wanted to see how the waveform |
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| 05:22 | as it propagates away from the So he went into this one room |
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| 05:31 | he built a wooden circle, wooden corral call it and he put his |
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| 05:40 | was about 10 ft in diameter. a borehole, a tube down there |
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| 05:46 | start pouring tar and then let it . Then he put his receiver in |
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| 05:53 | source in there and have another place there where he dropped receivers in, |
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| 05:59 | didn't have to be a board, dropped them in and held the wires |
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| 06:03 | that it later record. And they're very distances. So there is this |
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| 06:07 | ft diameter and he has all this with tar up to about 4 ft |
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| 06:14 | . Now, that was during the , he goes home to visit during |
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| 06:20 | summer time. Meanwhile, another entrepreneurs graduate student is building a model and |
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| 06:28 | needs some wood. So it goes and he takes the sides off of |
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| 06:32 | tower model and said, oh, solid. No problem. Only it |
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| 06:38 | hot in the room in the Even in Colorado, the tar melted |
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| 06:44 | they couldn't even open the door because door opened inwards and all this tar |
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| 06:50 | banged up against the door. They had a chainsaw, the doorknob in |
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| 06:57 | to get in. And after a of those chairman of the department's number |
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| 07:03 | physical models, we've had enough. here's an interesting note here until the |
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| 07:16 | fifties, the objective of Velocity Studies to find a substitute for checks shot |
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| 07:25 | used in time depth relationships. Anybody hear of a check shot survey |
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| 07:31 | You know whoever check shot survey, shots. You ever heard of |
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| 07:37 | You ever hear? Do you ever of a check shot survey? Have |
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| 07:43 | ever heard of one? You it's, it's right. Check |
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| 07:47 | sir. You did. Ok. checks out survey is after they get |
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| 07:55 | drawing a well, they will go lower a geophones to the bottom of |
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| 08:01 | hole. And up at the top , they have a vibrator and they |
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| 08:07 | vibrate and they will measure the time takes to get down to that. |
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| 08:12 | at 19,450 ft, they then move geophones up. 200 ft is a |
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| 08:18 | number and do this again every time measuring the travel time to a certain |
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| 08:25 | until they come up to the surface called a check shot survey. Sometimes |
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| 08:31 | distances are 500 ft in between. , another thing if you wanna get |
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| 08:37 | , very accurate, they do what's A VSP. Instead of having 200 |
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| 08:44 | separations, it might be 25 They do eight times as much. |
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| 08:50 | when they do that, they usually a cable that has 2030 geophones on |
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| 08:59 | . And that makes the, this go a lot faster and they pull |
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| 09:04 | . So what they have is they the depth and they have the time |
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| 09:09 | takes to go to that depth. they can actually just multiply the times |
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| 09:15 | two and they have the time to down and back again. So now |
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| 09:20 | go to their seismic data and they a reflector, they measure the time |
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| 09:25 | the seismic data. They go to check shot and say, who comes |
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| 09:30 | ? What depth are you at? they get the depth that they're at |
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| 09:35 | ft and they go to their their log and they look at the |
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| 09:39 | and say, what's it? 18,400 ? Oh, that's the Austin chalk |
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| 09:45 | in the top of it. So they've been able to correlate, they're |
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| 09:50 | logged data to the seismic using the shot survey. So that's expensive. |
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| 09:57 | the way, it's extra time that have that rig out there pulling up |
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| 10:04 | GEO phone and it takes time. Typically though they could do one in |
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| 10:10 | day. But when you start getting VSP type, now you're spending a |
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| 10:16 | of time when a Sonic log though developed, it was realized that ferocity |
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| 10:23 | to velocity and the Sonic log could used also. Now, in order |
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| 10:29 | do quote like a check shot they could use it to find out |
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| 10:33 | they are. But more importantly with Sonic log, they could make a |
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| 10:39 | seismic data. They can make a seismic map which they would then take |
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| 10:45 | correlate to the seismic data that they telling them now where they log is |
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| 10:52 | to the seismic velocity of an ideal . OK. When you have the |
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| 11:04 | , which is a P wave motion here you go ahead. If I |
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| 11:14 | my hands, what reaches you first a compression, I'm pushing particles away |
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| 11:23 | you. And that's represented by this portion right here. And then of |
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| 11:28 | portion then following that you have a fraction because if I push particles to |
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| 11:33 | , there's gonna be lacking some little back and compression. So this would |
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| 11:40 | a peak at compression trough peak so . Now this is when what's called |
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| 11:47 | acoustic wave. When I do it the air, there's no sheer wave |
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| 11:53 | in air. Because when I come , if I wanna generate shear wave |
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| 11:58 | , the propagation is going that But shear wave says the particle moves |
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| 12:03 | way. So I can't do this get the particles to move back and |
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| 12:08 | like this as it propagates over there there's no rigidity in air. |
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| 12:15 | this is the ground motion for a weight, it travels back and |
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| 12:20 | going up and down like this. see more on that a little bit |
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| 12:27 | . You can have a motion that's like this. And when you |
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| 12:35 | what does the p, what would P wave see sitting there? If |
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| 12:38 | have a sensor, I should say and it's a compression going that way |
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| 12:44 | wave, this is the motion you . If it's a sheer wave going |
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| 12:48 | this, you can go ahead and a sheer phone, it sees the |
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| 12:52 | motion. Yes. Why? what is the motion of the P |
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| 13:08 | S with linear rotation? Both? . What's rotation? Oh OK. |
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| 13:22 | this is a linear type of emotion back and forth because it's all along |
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| 13:29 | straight line. OK. And this rotational and it's kind of hard to |
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| 13:41 | to visualize. But on the sheer here, when I am at this |
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| 13:50 | , right here, if I look this line and if I look at |
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| 13:55 | box, the box is distorted now has the same volume, it's just |
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| 14:03 | in this direction. And then a later, it's distorted in that |
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| 14:09 | So at one particular time, that little vector goes like this and then |
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| 14:15 | on this way, it's going back forth. So at this one |
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| 14:20 | at that one location, you get and forth and I can measure this |
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| 14:24 | here and I can measure that angle , right there. And it's a |
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| 14:30 | one time, it's minus 10 degrees it's plus 10 degrees. So you |
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| 14:37 | actually a special phone called a rotation , which are popular among the |
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| 14:45 | They are extremely expensive because they're homemade . And there are 16 to |
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| 14:53 | They were, that was 10 years . I don't know what they |
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| 14:56 | Now. That is. So you only the sheer wave and not like |
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| 15:06 | motion right up here where I can P wave or shear wave and get |
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| 15:12 | same motion on the phone. We want that. This phone rotation only |
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| 15:19 | sheer wave. It will not measure the linear motion. Good question. |
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| 15:29 | . Anybody go to an engineering engineering degree. Anybody ever take a |
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| 15:36 | class in the in the physics Did you have strength of materials? |
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| 15:43 | other words, where you're given a and you try to pull it |
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| 15:48 | You never had that with the OK. I I, where I |
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| 15:53 | to school, everybody got an engineering . Uh they had to take the |
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| 15:58 | class as the first two years, three years almost and one is pulling |
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| 16:03 | bar apart and seeing what the strain . And so you have a bar |
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| 16:09 | they put a strain gauge vertically and and they pull the bar apart. |
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| 16:17 | you have clamps on here and you it downward. The original length might |
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| 16:22 | 10 inches, you stretch it, one inch and that's an exaggeration. |
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| 16:27 | break the dang bar if you did , but you stretch it one inch |
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| 16:32 | for a number and one inch over inches is gonna be defined as a |
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| 16:40 | and 1/10 has a value of So the strain is 0.1 that means |
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| 16:49 | better be plastic because something that what you see here is I know |
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| 16:58 | force. And if I divide that by an area, I have a |
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| 17:04 | and forgetting about the fact that this not a vector, it's a |
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| 17:09 | The force is the pressure is a field in one direction. So that |
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| 17:16 | that this is dimensionless delta L over meaning that E has to have P |
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| 17:27 | pos spur some pressure and E is a constant, an elastic constant part |
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| 17:37 | Books Law. This is an empirical when it says Hoax Law, it |
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| 17:46 | has to be defined. It's a approximation with Hooks. The law is |
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| 17:53 | we conduct this experiment, E is Young's modulus. How big is a |
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| 18:06 | ? Did I say? How much that vibrator weigh when it shakes the |
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| 18:11 | ? £60,000 30 tons? OK. . That's 10 inches. Bury it |
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| 18:25 | ft 3000 m 10,000 ft vibrators three , 10,000 ft away. It shakes |
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| 18:33 | in time. How much does it this 10 inch rock? Oh It's |
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| 18:42 | gonna strain it the 10,000 ft It's not gonna strain this rock. |
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| 18:47 | , if it doesn't strain this rock don't propagate through it. Oh I |
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| 18:52 | deeper reflections. Oh So this training . That's interesting. How much is |
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| 18:57 | training? How much do you really this rock? How much do you |
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| 19:05 | it now. I said I stretched by 0.1. You can compress it |
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| 19:11 | 0.1 too. But that's ridiculous. too big enough. So, what's |
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| 19:14 | strain? Are you a graduate Are you in Geophysics? You should |
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| 19:20 | this number. You're, you're right the rock physics lab, aren't you |
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| 19:33 | from, from, oh, uh, yeah, full time |
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| 19:45 | Surfer sws. You believe those surfer ? He's gonna get out of answering |
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| 19:53 | question. Ok. How much do think you str straight in? |
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| 20:00 | they say it's 10 to minus the 10 to the minus eight, |
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| 20:05 | did not know what 10 to the six means. It's very same thing |
|
| 20:10 | , well, I'm fine. I'm to ask for a budget of $7 |
|
| 20:19 | . 0 $7 trillion. Yeah, nothing. It doesn't bother you at |
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| 20:23 | saving $7 trillion. However, if came along and said I would ask |
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| 20:29 | a budget of $250,000 a month because relates to your salary. Now all |
|
| 20:37 | a sudden that's a big number. can relate to it, but instead |
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| 20:41 | showing me that you can relate 10 the minus one but 10 to the |
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| 20:45 | six, you can't relate to And that's why I put the bottom |
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| 20:48 | the screen on the Viber size What's the strain at 3000 m? |
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| 20:55 | of taking a core, think of a core, 100 m long. |
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| 21:07 | on the football field laying on the ? No, take one end of |
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| 21:13 | and make it solid and go to other end of the bulldozer and push |
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| 21:18 | end of the core. How much you have to push it? The |
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| 21:23 | of this paper is all, you to make this the width, not |
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| 21:27 | way, the thickness of the that's all. Now 10 to the |
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| 21:32 | eight, you have to squeeze it the thickness of this paper. All |
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| 21:39 | a sudden 10 to minus eight means don't string that rock at all. |
|
| 21:45 | yet our Geophones measure that our geophones the capability of something like 100 and |
|
| 21:56 | DB. I forget what that It's like uh two to the 22nd |
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| 22:04 | wherever the hell that number might And it's a marvel that they were |
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| 22:11 | so many years ago. And yet sensitive young is margins. Y'all. |
|
| 22:19 | we ready? We is the Did you get the boat? Did |
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| 22:25 | get the boats lined up? good. Just you talk about the |
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| 22:34 | . No, no, the, , the, the, the percentage |
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| 22:37 | the shape, right? So, your imagination, what's the size of |
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| 22:46 | QB nine? He said is, know that the change is 10 to |
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| 22:53 | six or minus eight. So what's size of that? You can the |
|
| 22:57 | of, well, everything strain the amount 10 to the minus eight. |
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| 23:02 | it's a big cube, it's 10 the minus eight, it's small, |
|
| 23:06 | 10 to the minus eight. So frequency will not influence your straight, |
|
| 23:13 | frequency we think is not really influencing drain. No, except in surface |
|
| 23:21 | because they're going deeper, the lower frequency like very down to the 3 |
|
| 23:29 | 3000. So they were all straight to minus 6%. And ok. |
|
| 23:41 | , if you have something at 6000 , 15,000, they all are going |
|
| 23:51 | switch. Ok. Here's your, call it an effective medium. In |
|
| 24:00 | words, a wave is gonna hit and effectively, it thinks of it |
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| 24:05 | a big surf, big area. I have an effective medium, the |
|
| 24:09 | of this room and this wave hits . It's gonna shrink it down 10 |
|
| 24:15 | the minus eight and that's very, small. Now take something that's this |
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| 24:24 | at the same depth, it's gonna it 10 to the minus eight. |
|
| 24:30 | , it's just linearly proportional. Want do it, the change of the |
|
| 24:40 | of change the shape, the frequency normally think of the frequency. It |
|
| 24:51 | not proportional to the ST the Yeah, it, it's still 10 |
|
| 24:58 | the minus eight. Um No matter you use a high or low |
|
| 25:08 | that is very misleading. No, , I I'll tell you why. |
|
| 25:31 | at the break, let me look up. I wanna show you, |
|
| 25:36 | , when you say linear, when say constant frequency, the same frequency |
|
| 25:45 | Hertz as an amplitude of 120 Hertz of one. That's in the frequency |
|
| 25:51 | . What's the size of that And the time domain? The voc |
|
| 25:59 | , but this the thing is, they going to be the same |
|
| 26:06 | Awesome. Last Johnson Bossy. If say something, let me uh bye |
|
| 26:39 | . Um zero 200. Got Yeah and 30 hoarding 20 birds. |
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| 27:20 | am specifying to pass the answer. is he of the 30 years. |
|
| 27:27 | is the 40 is the one for this band but it's three times low |
|
| 27:35 | . This damn weapon put three times frequency. That means that it would |
|
| 27:43 | like this same here. It's gonna like this question is what's the |
|
| 28:02 | Yeah, this is the problem we that what you like. That's this |
|
| 28:10 | but this has the same bandwidth as which it does you and have |
|
| 28:18 | 1020 40 4081. This is this here. It's the same ration |
|
| 28:29 | What's the the? Well, this have been won. What would that |
|
| 28:36 | to they say there there that the too. You make this happen |
|
| 28:47 | That yes, it doesn't want in to block the man thing. That |
|
| 28:57 | be so this will be for. . OK. That's good. Very |
|
| 29:10 | . That sounds good. I I the answer is it has to be |
|
| 29:18 | . Yeah, something like that. . That's a good, good |
|
| 29:27 | So when you're asking what strain, you define frequency thing, what does |
|
| 29:34 | mean to activate them? So, so if I can answer that |
|
| 29:47 | no asses problem. Thanks. Now, after all, you made |
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| 29:57 | do, are the boats ready for ? Yes, thank you. |
|
| 30:05 | It's been kept a secret. Geologists go and take a field trip. |
|
| 30:11 | go to the convention. They gotta on a field trip. Geophysics don't |
|
| 30:16 | a chance. Today we have a trip. The boat, the buses |
|
| 30:20 | gonna be arriving in about a half hour and we were gonna travel down |
|
| 30:26 | Galveston. We have the boats ready us and we're gonna go to a |
|
| 30:32 | uh offshore to the water depth is 300 ft. It gets right near |
|
| 30:37 | the shelf edge. Oh, the into the slope rather, I should |
|
| 30:45 | . And we have a rubber ball one of you is gonna take that |
|
| 30:49 | ball measure the diameter and then you're dive 300 ft and you're gonna have |
|
| 30:57 | caliper and at 300 ft you're gonna the diameter again. It's gonna be |
|
| 31:04 | because at 300 ft, what pressure you have on them? What's the |
|
| 31:09 | pressure at 300 ft? I always the rule of thumb. Half A |
|
| 31:14 | si per foot. It's probably 0.46 something like that. But a half |
|
| 31:19 | P ss I per foot means you have an additional 100 and 50 |
|
| 31:23 | si on that rubber ball. you can measure the size of |
|
| 31:31 | So you're able to measure the change the volume over the original volume. |
|
| 31:38 | have 100 and 50 P si, gonna measure K, which we call |
|
| 31:44 | bulk modulus. And it's done under hydrostatic principle there. Now, the |
|
| 31:50 | I go give you that whole goofy is because even I hope there are |
|
| 31:57 | donuts, ok? Because everybody has first year of eating donuts, |
|
| 32:03 | And you've been lacking, we've been track. You're too behind. |
|
| 32:08 | you got pockets, the um Bach Goofy story. It's easy to |
|
| 32:17 | Fred told me a goofy story. , I know how Bob Mo Bach |
|
| 32:22 | is major. It's relatively simple, to do sheer margins, not so |
|
| 32:29 | because I could take this core in afternoon. We're gonna remove this acoustic |
|
| 32:35 | and right above it is a stainless flight detached to the ground. Don't |
|
| 32:44 | about that way. And I would the score and glue it to that |
|
| 32:50 | . And then with my dynamic I'm gonna adjustable hand, I'm gonna |
|
| 32:56 | it with the known force off to side, creating an angle and one |
|
| 33:01 | you will be given a oh my . I can't remember the name of |
|
| 33:07 | thing. Majors angles uh ProTrac or a protractor, but rather than me |
|
| 33:14 | degrees, it will be in So you measure this is radiance and |
|
| 33:20 | turns out it's gonna be a small . So that angle you measure is |
|
| 33:25 | the sheer strain. So here we've the sheer string and I know with |
|
| 33:31 | calibrated hand what force I pulled on sounds great, Fred. Except for |
|
| 33:37 | thing, the glue will give way here. OK. I'll clamp |
|
| 33:43 | There you go, clamp the, , you're gonna break the particles right |
|
| 33:47 | . At this end. We'll start break apart. Hey, sheer strain |
|
| 33:52 | not as easy to measure, is ? No. And this is why |
|
| 33:56 | go to the dynamic measurements. These the static measurements, the dynamic we |
|
| 34:04 | P wave and sheer wave in order measure the strain, I should say |
|
| 34:10 | sheer modulus velocity sheer moguls over the , sheer wave, sheer rigidity over |
|
| 34:23 | square root gives a sheer wave You notice this is an alpha and |
|
| 34:28 | is a beta and most of the literature you're finding P wave is always |
|
| 34:34 | sheer wave beta. Why? Very . It was named after the |
|
| 34:44 | What's the first arrival, the P called alpha first in the alphabet? |
|
| 34:49 | the second wave this she call it ? And that's how it sort of |
|
| 34:53 | about. It's my story and I'm with it. Hey, Fred. |
|
| 34:59 | , I had a question on the slide, if uh I don't know |
|
| 35:03 | you wanna finish. Uh, we're least I was having a little bit |
|
| 35:07 | trouble hearing you at some parts. uh what at the bottom there? |
|
| 35:11 | says, what is the significance of strain of 10 to the negative? |
|
| 35:16 | ? What, what was the answer ? OK. I, I started |
|
| 35:21 | give an analogy which is probably But do you ever listen to President |
|
| 35:27 | Biden? Mhm. And do you listen to what they say? The |
|
| 35:34 | versus the Republicans? And here's how goes, Congress Senate. I'm gonna |
|
| 35:42 | for a $7 trillion budget. That's , Joe. No problem whatsoever. |
|
| 35:50 | , you said, OK, it five last year. What's the |
|
| 35:54 | $7 trillion means nothing to you? this is the scenario that I used |
|
| 35:59 | the classroom. I'm sorry. But , but I'm gonna reward it. |
|
| 36:04 | Biden said, I'm gonna give a . I don't have a new |
|
| 36:09 | $250,000. All of a sudden, , just a 2nd. $250,000. |
|
| 36:16 | come so much? Because it becomes to your salary? And you can |
|
| 36:21 | the significance of the number 10 to A trillion dollars 10 to the |
|
| 36:26 | You have no idea what it It, it just doesn't register. |
|
| 36:31 | , the number 10 to the minus does not register until you give a |
|
| 36:36 | experiment which we did here to show m core only has to be compressed |
|
| 36:43 | width of a paper. I the thickness of a paper and |
|
| 36:48 | and that's 10 to the minus six . It's just a bump on the |
|
| 36:53 | . Now, the other reason is you only strain it 10 to the |
|
| 36:59 | six, think about this another way what if I put gas in that |
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| 37:09 | and I had this 10 to the six. Hey, it doesn't take |
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| 37:15 | gas in order to be 10 to minus six filling of the porosity. |
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| 37:20 | just have to squeeze it a little and you're still safe. So |
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| 37:25 | that's sort of analysis. It's a amount squeezing in there. Gotcha. |
|
| 37:32 | you so much. Here are the wave and sheer wave and just to |
|
| 37:44 | you, I can copy just as as anybody else. We see that |
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| 37:49 | giga pascal is what they're usually given is 10 to the 0.4 or five |
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| 37:57 | 10 to the fifth P si when at 10,000 ft, you have a |
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| 38:04 | SI in the water of about 5000 si and that's 34 mega pascals. |
|
| 38:14 | you see the values for K in , in literature, they are normally |
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| 38:22 | in giga paal. And a lot times you say, oh, it's |
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| 38:26 | to the fifth something or 10 to 10th. Assume their gig of pass |
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| 38:30 | K would be something like 3230 for , 71 for limestone mu for, |
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| 38:41 | quartz is actually a little bit larger the bach modulus. If I take |
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| 38:49 | non porous sandstone made all courts, the K and the U values in |
|
| 38:59 | density, plug them into that You're gonna come out with something in |
|
| 39:05 | order of 20,000 ft per second would what a quartz grain propagation of |
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| 39:12 | I think somebody gave me 19,900 ft second. When I asked for what |
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| 39:18 | a sandstone velocity? And that's then the theoretical value using what they reported |
|
| 39:25 | literature for measurements in the lab? . Is anybody going for the |
|
| 39:42 | Yeah. How many papers do you to publish your journals? What's |
|
| 39:51 | Just one? Have you did You're a geologist? OK. I |
|
| 40:00 | the dean one time. That's kind interesting in order for a professor to |
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| 40:07 | promoted and have a salary increase. many papers do they have to publish |
|
| 40:13 | year? Pure, pure review Three, five. What's that? |
|
| 40:25 | need? Three, three papers a as a professor? And who's told |
|
| 40:31 | that number? Ok. Here's the response. You're, you're, you're |
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| 40:40 | on there on that. It all upon what department you're in. If |
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| 40:46 | in biology, then the number of that he expects might be 20. |
|
| 40:55 | the reason why it, yes, your reason why you'll spend four years |
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| 41:02 | at a particular formula. Some call new feed for cows and you will |
|
| 41:12 | that, feed it to cows and take measurements. That was for a |
|
| 41:20 | steer. What about a milk, cow? What about a rema |
|
| 41:29 | So you get all those versions and what about a squirrel? What about |
|
| 41:35 | , all of them should be All new new research he says, |
|
| 41:40 | that's why he expects a lot. says for math, these are sometimes |
|
| 41:45 | they write one paper in five it's good because math is so hard |
|
| 41:54 | get published. They are such elitists what could be published really, really |
|
| 42:00 | . It's, it's like why in of Houston, do we not have |
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| 42:09 | members of the Academy of Science Geological ? Because the people that go ahead |
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| 42:16 | select are people like from rice word Sot Earth Geophysics and we are not |
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| 42:23 | earth geophysicists. And therefore if you on engineering geophysicists or exploration geophysicists, |
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| 42:32 | not gonna get selected. Some of better paper research were done by expirationist |
|
| 42:39 | uh processing some of the algorithms were passed on. For instance, not |
|
| 42:46 | my smartness. One of my graduate , Tom Morgan, professor at uh |
|
| 42:52 | I now a research he did the transform migration by ST Madam and that |
|
| 43:04 | 10, 100 times faster than the method. He went up to the |
|
| 43:11 | Institute where they're trying to work on S and cat scans and they had |
|
| 43:18 | process the cat scan and they were the old Kirkoff method and he introduced |
|
| 43:26 | for a transform stort method and all a sudden what we're taking them to |
|
| 43:32 | days to process cat scans, they're instantaneously. You get that running |
|
| 43:38 | they're seeing the pictures on the They couldn't believe that they wanted to |
|
| 43:43 | him an award and it was just but it's already been published for five |
|
| 43:48 | . And that's the problem. We steal enough in our science. |
|
| 43:54 | we we should be borrowing from other . We have examples. Poisons |
|
| 44:01 | Poisson grew up in the time of and some of the other great mathematicians |
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| 44:07 | he said when you squeeze the it it also gets fatter. So |
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| 44:14 | measured the facticity factor. The amount strained horizontally over the monastery vertically that's |
|
| 44:30 | post on ratio. And to get ratio from the dynamic that is propagating |
|
| 44:45 | is shown here. And if you get V PV S over the poison |
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| 44:51 | exchange, the rate of the relationships to express poison's ratio using the sheer |
|
| 45:01 | the P. And comparing it to static measurement is no simple task. |
|
| 45:07 | G oh yeah, just a little of algebra bull crap. You get |
|
| 45:12 | thermodynamics trying to do this. It not a simple type of a relationship |
|
| 45:17 | go from a static into a I prefer poison's ratio. Leon Thompson |
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| 45:26 | VP over vs. Leon one time I prefer VP over vs because you |
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| 45:35 | have two VPs, two different P velocities, two different shear wave |
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| 45:41 | And so using Poisson's ratio defeats the and we didn't tell him that Leon |
|
| 45:52 | engineers have poisons ratios in direction in this direction. And that two |
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| 45:59 | too. They've had that for Uh not just one direction but Leon |
|
| 46:06 | up with VPOV. I grew up poison. He and I went to |
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| 46:11 | together. Butch Poussaint was his Did anybody know Butch? Yeah. |
|
| 46:19 | . PSA was his dad's last His dad was a very rich merchant |
|
| 46:26 | songs. His dad was a meat . They called them butchers is a |
|
| 46:34 | cutter butchers and they couldn't call the new child butcher. They just |
|
| 46:42 | him Butch. And that's how he his nickname, Butch Poussaint. You |
|
| 46:52 | that story? OK. That's totally . My colleague for marathon heard me |
|
| 47:02 | that one time. And the next he brought me in a writing on |
|
| 47:06 | Poussin's biography autobiography. He said he come from a rich merchant family and |
|
| 47:16 | had a nanny and this nanny would to the market because she prepared |
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| 47:22 | the meals every day and she hung on the hook in the kitchen and |
|
| 47:28 | had these overalls bib overalls where he straps in the back. She took |
|
| 47:32 | straps and hooked them up and he he'd swing violently in order to try |
|
| 47:39 | get off of that. He says thinks this is the why he spent |
|
| 47:44 | lot of time developing the laws in of a pendulum, which he did |
|
| 47:50 | because of his swinging back and forth a child. That's his story on |
|
| 47:56 | rich uh merchant. Ok. Enough that, let's look at theoretical |
|
| 48:05 | practical limits. Ho on ratio is zero to 0.5. Leon Thompson in |
|
| 48:11 | classical article on the leading edge said , no, no, no. |
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| 48:15 | minus one to 0.5. Although anything zero to minus one is only observed |
|
| 48:23 | cer certain minerals that I think have be created in the lab. So |
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| 48:31 | the way it goes. If you a volume and you strain it, |
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| 48:37 | the volume and it has no ex extension, sideways voice on ratio is |
|
| 48:46 | . So as you squeeze it, it doesn't get fatter, your poisons |
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| 48:51 | is zero. No, if you it and the final squeeze volume is |
|
| 49:00 | same as the beginning volume. Your sons ratio is 0.5. Now, |
|
| 49:08 | the questions. When you squeeze a like this blue box is squeezed, |
|
| 49:16 | doesn't get fatter, it only gets . What type of material can you |
|
| 49:25 | ? And it doesn't get fatter not at not rocks, just rocks |
|
| 49:37 | . A sponge. You take a and you squeeze it, it doesn't |
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| 49:44 | fatter, you can almost squeeze it zero volume in what material that you |
|
| 49:52 | ? No volume change. And that's fluid. So we have two ends |
|
| 49:58 | zero, which is a sponge to . A fluid rocks fall in |
|
| 50:04 | So the rocks poisons ratio is between sponge and fluid interesting concept. But |
|
| 50:11 | will use this shortly. There's a other definitions. It's kind of |
|
| 50:19 | If you take a look at vs over P squared posts ratio, it's |
|
| 50:28 | like a straight line. And he here's what Mike wants us to |
|
| 50:33 | out is if you log gamma to vs over P squared, look at |
|
| 50:39 | way gamma is 0.5 minus poisons one minus point over sigma, which |
|
| 50:47 | Poisson's ratio. They're the same relationship you think of gamma is BVS over |
|
| 50:53 | squared. Ok. Now, how we make use of this material that |
|
| 51:08 | talking about? If I go ahead drilled down to 10,000 ft, 8000 |
|
| 51:26 | and I get a bunch of sandstone and they measure the porcelains ratio, |
|
| 51:33 | gonna be about a value of And of course, it's gonna be |
|
| 51:38 | of a bell shaped type of a , but that's approximate where they're gonna |
|
| 51:44 | . Now, at the same time the same depth, if I measure |
|
| 51:48 | poisons ratio of shale, they're gonna very close to that of the |
|
| 51:52 | but they're gonna be a little higher ratio. A little bit bigger. |
|
| 51:59 | then finally, what about limestone? , bless that limestone. I don't |
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| 52:05 | if it's a gift or not, limestone dolemite, they kind of sit |
|
| 52:09 | the range of 0.3 0.33. They change much. You have to get |
|
| 52:14 | , really high porosity for them to change it. Stick it around |
|
| 52:20 | No, if you take shell and and go shallower, what happens? |
|
| 52:29 | , as you get shallower, you in this direction because what's the |
|
| 52:39 | You can get a sand. It's the Rivermont Delta and you put a |
|
| 52:46 | in and you pull up four screen . That is the beginning of a |
|
| 52:52 | Sana. That's a fluid. It's go ahead and have a point ratio |
|
| 52:58 | 0.5. So the shaller we get more of these two, these two |
|
| 53:07 | shaped distributions will come up to get to 0.5. The deeper you |
|
| 53:17 | the sandstone starts going down, getting and even smaller than 0.1. But |
|
| 53:25 | doesn't decrease that much. It kind stays there. It gets a little |
|
| 53:29 | less but the sandstone, it can way down here. Yeah, but |
|
| 53:36 | you put gas in the sandstone, goes way down here. Uh Hold |
|
| 53:45 | , Fred just a second. You you put gas in the sandstone. |
|
| 53:49 | was wa yeah, gas is up fluids are up here, not down |
|
| 53:54 | for it. Why we putting gas a sandstone make it get smaller poisons |
|
| 54:01 | and not a bigger because this is sponge down here and over here these |
|
| 54:07 | the fluids, the gasses sitting up that needs to be asked why. |
|
| 54:16 | answer it. Here's a plastic bottle with sand grains and water and if |
|
| 54:27 | squeeze it, push it down the which were approximately run, now start |
|
| 54:38 | flatten out. And what has happened as you're squeezing, these greens were |
|
| 54:47 | to take the space of the But the water says, no, |
|
| 54:51 | not, I'm not reducing myself for . Go ahead, make the bottle |
|
| 54:56 | bigger sideways. So it does and a water saturated water does not yield |
|
| 55:03 | space to grains as grains are they go sideways. Meanwhile, if |
|
| 55:11 | filled the same plastic bottle with gas the grains of sand and if I |
|
| 55:17 | them down, what happens? The doesn't get thicker. The gas san |
|
| 55:23 | take my space. That's OK. wanna get fatter, take my |
|
| 55:27 | no need to go ahead and make difficult. So the gas saturated, |
|
| 55:34 | don't get fatter. They act like sponge. When you look at the |
|
| 55:39 | entity, gas sands respond similar to sponge. Changes are safe vertically but |
|
| 55:48 | change horizontally. OK? Before we this, it looks like we're time |
|
| 55:56 | our my God. You deserve an , you know that God Stewart Rob |
|
| 56:12 | is the director of the Seismic Acoustics , right? Or a GL |
|
| 56:20 | When it was first started, we doing 3D modeling 3D analysis. |
|
| 56:27 | we thought we were good. We theoretical models migrated in 3d, made |
|
| 56:33 | model migrated. So we thought, think about thinking. And so we |
|
| 56:40 | a helmet and we put transducers all the helmet and we went ahead and |
|
| 56:48 | to go ahead and migrate the the respon electrical responses to see that |
|
| 56:57 | concentrate at a particular spot. But , you gotta get somebody that's thinking |
|
| 57:04 | the time. Unfortunately, graduate students a meandering mind. They don't concentrate |
|
| 57:14 | effectively unless they're asleep and you want in deep sleep. So, what's |
|
| 57:22 | best time to get a graduate student deep sleep? 20 minutes after |
|
| 57:31 | And you haven't gone deep sleeping? , I congratulate you folks. Let's |
|
| 57:35 | a break now. Ok. and it's sh she, you can |
|
| 57:48 | II I screwed up again. You there'll be a set up and you |
|
| 57:58 | , yeah, that's it. So can drag to this to the other |
|
| 58:03 | they would block now. They will block you. Ok. Oh, |
|
| 58:07 | , you can hide it too. . Yeah. No, I could |
|
| 58:15 | this in. Can you see my now? Yep. You can. |
|
| 58:38 | . All right. This is a . By the way, you'll need |
|
| 58:43 | , quarter sheet. Of paper and might want to close your books, |
|
| 58:57 | . That's a really big yawn for early in the afternoon and it's well |
|
| 59:01 | the 20 minutes. Wow, this taken directly from the W paper. |
|
| 59:22 | is one of the rules of thumb probably one of the rules of |
|
| 59:31 | That's most important if you want. can say this another way, |
|
| 59:38 | rocks with a higher clay content have blank, low seismic velocity and they |
|
| 59:46 | have a higher or lower seismic Think of it that way. Take |
|
| 59:50 | word properties and put velocity there. might make more sense. Rocks with |
|
| 59:57 | higher clay content have a seismic velocity bigger or lower than rocks with a |
|
| 60:06 | clay in them. That's what it's to put velocity for properties when |
|
| 60:12 | when we email it. Are you with just typing it in to the |
|
| 60:17 | ? Well, as long as I the email, if that typed |
|
| 60:20 | you can just write the word higher lower. That's all you know, |
|
| 60:24 | don't have to attach, you don't want us to attach like just send |
|
| 60:28 | an email with the word higher or and a piece of quarter sheet of |
|
| 60:33 | with higher or lower. It's all need. Yeah. No. |
|
| 60:49 | No. ST and give this to . Is she here? Yeah, |
|
| 61:08 | think it's that one. You right . Yeah, I ended up emailing |
|
| 61:20 | the one this morning, I was wait to come in and just do |
|
| 61:23 | in person really quick. But since said something about me, what do |
|
| 61:29 | want me to do? I forget I was supposed to do. I |
|
| 61:32 | , I can tell you that there's , what's the answer? Uh The |
|
| 61:37 | was velocity and then the TB is solo for the first equation and the |
|
| 61:44 | was the, no, the name you think that's right? OK, |
|
| 61:53 | . You also emailed me, didn't ? OK. No. OK. |
|
| 62:01 | have to take a class on how make a quarter sheet of paper. |
|
| 62:11 | did some good though. What's No, I spent a whole a |
|
| 62:20 | five minutes explaining how to make a , folks, it's to write one |
|
| 62:47 | does not take five minutes. You to see the word exercise now and |
|
| 64:21 | am wiggling my pan around. Got . Thank you. OK. Now's |
|
| 64:28 | time to make some money, All right. Have you known each |
|
| 64:35 | ? More than two days? You a night? No, you |
|
| 64:40 | Taylor doesn't know anybody. Procida. don't know anybody either. Yes. |
|
| 64:45 | know nobody. OK. I can't you but maybe other people can. |
|
| 64:52 | . II I know. OK. I told you you have to earn |
|
| 64:59 | . Now there are 14 of I can't take answers from all |
|
| 65:03 | So we're gonna have to go ahead select one and I thought first of |
|
| 65:10 | . We need a game. there's a lot of people here that |
|
| 65:16 | be from other places in downtown So I'm trying to select a game |
|
| 65:22 | known worldwide. Like Who Wants to a Millionaire? Ok. So what |
|
| 65:29 | do? 14 contestants, you select person to represent you to make all |
|
| 65:34 | money. So can you select one among you in order to make all |
|
| 65:41 | money? I can see. We champions in each division here. Division |
|
| 65:51 | sitting here in the room. Division sitting on the web. So on |
|
| 65:56 | web, uh Kelly, you're the of organizing your committee to get a |
|
| 66:06 | to be the one to answer the . And does that mean I here |
|
| 66:17 | Delrio, you're going to be our to select the person among your seven |
|
| 66:23 | who do you want to select to the questions? You can ask other |
|
| 66:32 | you ask for volunteers if you want , somebody might volunteer. Anybody wanna |
|
| 66:41 | . Now you're gonna make me pick Taylor. So sorry, you got |
|
| 66:49 | . You got somebody. Yes. that? I, I've been |
|
| 66:56 | You got somebody select. OK. . OK. We have a selection |
|
| 67:02 | division B. Taylor was volunteer. a good way to put it. |
|
| 67:15 | gonna help you Taylor. We have now you can help. Sometimes I'll |
|
| 67:21 | you when you can help. Do have somebody here from this group? |
|
| 67:32 | can do it. Ok. Now got two people, we gotta select |
|
| 67:39 | . We have the Darrio who doesn't a face because she's not on the |
|
| 67:44 | . Uh, or you can sit this chair and the other people can |
|
| 67:48 | you because we can see Taylor. wanna do that? Ok? You |
|
| 67:53 | wanna do that. Ok. I'll you what I'm gonna do. I |
|
| 67:58 | write a number on a piece of . Each one of you are gonna |
|
| 68:01 | the number, whoever's closest that happens be the, uh, one designated |
|
| 68:09 | going ahead. Uh, ok, wrote the number down Del Rey. |
|
| 68:16 | your answer? 1 to 10, day time. 1010, 10. |
|
| 68:30 | number is two, two. So real, it looks like you're gonna |
|
| 68:40 | making all the money. Ok? , remember if you lose, you |
|
| 68:45 | the money for everybody. Ok? don't want that to be any pressure |
|
| 68:50 | you. Ok? We're gonna play Wants to be a Millionaire and the |
|
| 68:58 | of money I'm not allowed to tell immediately. They will take income tax |
|
| 69:08 | of this before you get, receive check. So don't be upset if |
|
| 69:13 | happens. Ok. The way this is to be a millionaire, I'm |
|
| 69:25 | to give you a question and you four options. Normally to answer |
|
| 69:33 | you choose which one you want. by chance you don't happen to have |
|
| 69:40 | answer immediately. You have three You can ask the class person what |
|
| 69:46 | think it is and see what their is. Or you can ask me |
|
| 69:54 | randomly throw away two of the four or three. You can call a |
|
| 70:02 | . I'm not a friend by the . So in order to answer |
|
| 70:05 | OK, if we get, now here's the question, which arrow |
|
| 70:23 | move first when a hammer strikes this , assuming that the transmission of the |
|
| 70:35 | going through this plate is instantaneous. these coils start to vibrate up at |
|
| 70:42 | top, at the bottom is an . Five of them label A through |
|
| 70:48 | which one would move first whenever you that hammer on there. No, |
|
| 70:57 | see your thinking, which is Uh I'm glad you're giving me a |
|
| 71:00 | . Now you have the option. you one to ask the cla uh |
|
| 71:07 | the class, ask me to remove out of these five or call a |
|
| 71:13 | . I see she's deciding, I to ask the audience, she's going |
|
| 71:18 | have audience participation. I don't care you say. This is my |
|
| 71:22 | You, you too. I, play fear, my fear. |
|
| 71:31 | So audience raise your hand. Let get the other audience. Everybody |
|
| 71:37 | audience, 1234, I need somebody . 1234567. Those who think number |
|
| 71:56 | or I should say I can't get here. Let's try this one. |
|
| 72:04 | a will move first. Now, me tell you what these are |
|
| 72:10 | is a piece of plastic that you in there like a, what do |
|
| 72:16 | call a slinky type of a And B is the same as |
|
| 72:23 | except the plastic is replaced with steel Bot. Modulus C has a lot |
|
| 72:34 | rungs in it. Then B D replaced all empty space with glue and |
|
| 72:46 | is a solid rod. So audience , raise your hands. Who thinks |
|
| 72:56 | would be the first to move? your hand. OK. Over there |
|
| 73:01 | have that mot OK. In this ? A OK. Let me make |
|
| 73:05 | total of that total for a was was just gonna get OK. |
|
| 73:10 | OK. How many think B would the one? Oh OK. C |
|
| 73:26 | thinks C would be it? Are sure think closely folks? What's |
|
| 73:41 | OK. We got 10 Thanks we got one. We got at |
|
| 73:45 | one. That's right. D who it's de anybody? Raise your |
|
| 74:00 | OK. We have none. And does anybody think E is the |
|
| 74:10 | We have? 1231234, just What material is a plate made out |
|
| 74:38 | ? What's that? What material is plate made out of the plate is |
|
| 74:43 | out of what we call the fastest . In other words, it's |
|
| 74:49 | We make sure these all start going . This experiment has been conducted |
|
| 74:58 | Times successfully. Ok. Del what it is is you have one |
|
| 75:10 | sea and 13 through whats your E she selects E do you wanna |
|
| 75:20 | a down as your final answer? answer is E ok. Now you |
|
| 75:28 | have my notes to see what the is. Ok. The answer is |
|
| 75:43 | first to arrive is E now, , why is e the first to |
|
| 75:54 | ? But over here we have a that's made out of plastic and it's |
|
| 76:00 | to vibrate back and forth. If ask what velocity is related to, |
|
| 76:08 | related to the bulk module and sheer . When you go from plastic to |
|
| 76:15 | , your bulk modulus increases. So is faster than a now C you |
|
| 76:24 | more rungs in there having more Basically, you have a stiffer |
|
| 76:34 | It's like the new spring you put your back door and when you open |
|
| 76:40 | in the beginning of the summer, better get your butt eye fast or |
|
| 76:44 | gonna come slamming back on you really D is I try to make something |
|
| 76:52 | no void. So put glue in , but it has the same stiffness |
|
| 76:56 | greater than the steel in the Finally, it's a solid, it |
|
| 77:06 | no holes in it. So it no holes in it. It has |
|
| 77:10 | weakness. It's gonna take on the material, which is all steel. |
|
| 77:16 | the question you're saying is I know much money we're gonna win Fred. |
|
| 77:21 | how is this related to the lithology poor fluor? So we go back |
|
| 77:27 | this again and we see a, a sand. It has a high |
|
| 77:35 | in its gas fill. And then keep the high porosity in the |
|
| 77:42 | But we change the lithology mineral to line. We now have a, |
|
| 77:47 | limestone sitting in there and that has higher bulk modulus, 71 versus 65 |
|
| 77:57 | 42. 40 are just saying, , I had the same material, |
|
| 78:03 | steel gas still in there. But lowered the porosity. When I lower |
|
| 78:08 | velocity, I increase the velocity. seen that many times and then we |
|
| 78:15 | ahead and we go from gas too . Now, we have a stiffer |
|
| 78:23 | in the pore space and it's gonna faster. Finally, you have a |
|
| 78:29 | rod that we think is the fastest we know it is, we put |
|
| 78:36 | steel rod on the table, you your ear on one end and somebody |
|
| 78:40 | it. It's instantaneous. You can that. Heck, you put the |
|
| 78:45 | rod on the floor. Take number here, which is a, a |
|
| 78:52 | slinky and you pull it, you walk faster than the back and |
|
| 78:58 | goes down the length of that So the answer is number East and |
|
| 79:07 | now has shown how the lithology was . We went from sand to the |
|
| 79:16 | . The porosity. We go from to low porosity and the poor |
|
| 79:22 | we go from gas to wet and is the three petro physicals properties. |
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| 79:29 | think of nothing but a spring Ok. Very good. Second. |
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| 79:50 | me get up water. Oh. , thank you, ma'am. I |
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| 79:59 | it. Anybody run into construction this . Coming over here. Anybody take |
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| 80:17 | 10, I usually did. I to take, I spent an hour |
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| 80:25 | to figure out which is the best to go. Here are some of |
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| 80:35 | factors that are affecting velocity. A overview. It, it it kind |
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| 80:40 | summarizes some of the stuff that Wayne in his article in the summary, |
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| 80:48 | instance, velocity is always on the axis and I change the property the |
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| 80:54 | and the X axis, for fluid density, light gas, heavy |
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| 81:01 | , really heavy water now and as fluid density increases, so does the |
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| 81:11 | . And you might think this is Fred because in that equation, velocity |
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| 81:19 | equal to square root of rock moduli density. It seems if you make |
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| 81:27 | rock more dense, it should be because you divide the rock moduli by |
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| 81:34 | density. Oh What happened to that ? Velocity is equal to the square |
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| 81:44 | bulk modulus plus four thirds sheer rigidity by the density. So if you |
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| 81:51 | by the density, if that density bigger, the velocity should get |
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| 81:56 | But here it says the velocity gets . Why? Because as you change |
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| 82:10 | pore fluid, you're changing the bulk of the total rock. And as |
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| 82:17 | turns out, as you add that bulk marginalized gets higher. So |
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| 82:23 | rock properties are getting higher, faster the density is getting increased. |
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| 82:32 | When we look at that velocity, , we see things like cool and |
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| 82:39 | of the places you, I gave an example where the coal was so |
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| 82:46 | . I mean, it's like 7000 per second. The sands and shells |
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| 82:51 | 14,000 ft per 2nd. 2 to . The density of coal is so |
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| 82:58 | . 1.2 g per CC compared to g per C for the sand and |
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| 83:06 | , cool sunlight and almost floats. as you get denser material, the |
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| 83:18 | mogen light gets faster, bigger dole be and the fastest now age and |
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| 83:29 | we should have separated. These should these one at a time. So |
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| 83:34 | do an experiment, other experiments. lot of experiment. Here's my favorite |
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| 83:39 | property. This is a rock right . That's my test specs. And |
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| 83:42 | I'm gonna do, I'm gonna bring a piece of electric crystal put on |
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| 83:46 | of the bottom, spark, the on the top and see how long |
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| 83:50 | takes to go through and that you're take that time divide by the length |
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| 83:55 | that rock specimen and go ahead and that as my initial test. |
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| 84:03 | you can join me in this I wanna go ahead and leave and |
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| 84:06 | back in about 25 million years. what we're gonna do is hope the |
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| 84:13 | doesn't rise and the building doesn't get away and run the experiment again. |
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| 84:18 | you think I'll get the same result be faster? Should be, it's |
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| 84:22 | , right? Why should the Why shouldn't I get a, |
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| 84:26 | a faster velocity? I thought older had faster velocities and I'm gonna wait |
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| 84:32 | million years. So why should my be faster? Seems logical to |
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| 84:41 | You believe it when you read it , walk faster velocity. Yeah, |
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| 84:45 | why it's not the age is it could teasing us? We're damn, |
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| 84:53 | trying to get a nap and you're keeping us awake. Ok. |
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| 84:57 | the rock is faster after 25 million because it's deeper, has more compaction |
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| 85:06 | it has more digenetic change. There's calcite silica deposited from the pores so |
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| 85:14 | this contact now you don't have a space for the grain. It's solid |
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| 85:19 | through there. Now, as far the age is the depth is |
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| 85:25 | we find rocks that are like the rock as a function of depth. |
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| 85:30 | velocity is almost linear right here. just only at right about here. |
|
| 85:36 | top does it actually start with a curved surface? But that's actually kind |
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| 85:42 | hard to measure because we don't get velocity readings up shallow. And |
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| 85:47 | I really don't know, is that interpretation of what the log should read |
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| 85:52 | is that really what the velocity No, we come across these very |
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| 86:00 | rocks and something interesting happens at the beginning, the velocity increases fast. |
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| 86:07 | then after a while after a certain , it kind of flattens out. |
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| 86:11 | what's happening at the initial stages that to be the cracks, the micro |
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| 86:18 | are closing at a certain depth like kilometer, maybe two kilometers. And |
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| 86:25 | you get down to two kilometers, cracks are all close and the velocity |
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| 86:30 | linearly now don hit water saturation. see up at this end here where |
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| 86:41 | have all water, the velocity is high and then you just add a |
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| 86:46 | bit of gasses the gas and maybe 10%. And all of a sudden |
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| 86:53 | velocity drops quickly and then it kind stays the same velocity. It doesn't |
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| 86:58 | how much more gas you put into . Why? Because once you put |
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| 87:04 | little bit of gas in it, weakened the structural modulus of the rock |
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| 87:11 | anymore it's not gonna matter, you've weakened it. And then if it |
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| 87:16 | change, it tends to get faster you add more gas because you're making |
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| 87:22 | rock lighter and you're dividing by density Mar just stays the same, it's |
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| 87:29 | by the density ferocity we all could the old log analyst who's in the |
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| 87:38 | room all the time, ask And I said, oh yeah, |
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| 87:41 | you increase the fro the velocity decreases as you put more holes in that |
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| 87:49 | , you're losing its strength, you're the bulk moduli not cementation. That's |
|
| 87:59 | interesting one because as you have more , let's go and take a look |
|
| 88:06 | a rock like this. This is rock right here and here it has |
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| 88:10 | grain, one of the grains now here's another grain and there's sort of |
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| 88:17 | ring that touches one surface, that edge right there. What if I |
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| 88:23 | cement all around that ring? So increase that contact there? Well, |
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| 88:30 | soon, all the contexts are it's almost like a solid rock. |
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| 88:36 | the velocity gets faster with more OK. The one you're all waiting |
|
| 88:46 | poor pressure, over burn pressure. one of the most important concepts in |
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| 88:52 | about velocity is gonna be the differential often call the effective pressure. My |
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| 89:07 | rock specimen right here, we're gonna an experiment. I'm going to go |
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| 89:15 | and put this in a steel cylinder I'm just gonna squash it from the |
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| 89:23 | . And as I squash it, grains get closer together, they start |
|
| 89:29 | flatten out. You're getting more area , the velocity gets faster. So |
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| 89:37 | more overburdened I apply to this, more the greens are gonna get smashed |
|
| 89:44 | faster the velocity, but you gotta there because now that steel cy |
|
| 89:51 | I'm gonna start pumping in fluid and pump that fluid in. And when |
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| 89:57 | do that, I increase the pork which pushes the grains apart. So |
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| 90:04 | I reduce the velocity because the grains getting pushed apart. So it's not |
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| 90:10 | the over burn pressure and or the by itself, it's the difference. |
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| 90:16 | the overburden minus the poor pressure gives what's often called the effective pressure. |
|
| 90:24 | that is what determines what the velocity going to be. And mostly in |
|
| 90:31 | R report. As far as the san ratio is concerned, usually the |
|
| 90:39 | clay you add as our little quiz the lower the velocity but not always |
|
| 90:46 | will show you when Pr Z summaries Wang had in his article and also |
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| 90:58 | Eth writes in his book. That's good book. By the way, |
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| 91:02 | you're interested in quantitative interpretation, it's older book. Now he comes out |
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| 91:07 | Stanford. That's an excellent job. good. Now, in this |
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| 91:14 | we see lithology is a description of rock's physical characteristics, is a little |
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| 91:19 | hand lens and I put up at top 34 stars and these actually represent |
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| 91:29 | phys properties. So in rock what's the most important in rock properties |
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| 91:36 | the lithology and the porosity. the poor shape. We'll hold on |
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| 91:41 | that as far as the fluid properties the saturation. These are the very |
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| 91:48 | ones that's the most important then the oil ratio and the fluid type, |
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| 91:54 | the API number is important over the . It's the net poor pressure that |
|
| 92:02 | no a guy by the name of his name? Fred Guide to Stanford |
|
| 92:15 | started Stanford lab Amos nor he developed for the lab, wrote books, |
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| 92:25 | cetera and it was very famous for the articles published that write all the |
|
| 92:34 | in the book. He kind of Stanford and oh, he was |
|
| 92:39 | he was everything at Stanford sharped up he formed a company and it's one |
|
| 92:44 | in Houston. I think it's called . And what he does is take |
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| 92:51 | and makes CT scans of them at high resolution and gets the poor shaped |
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| 93:00 | . And from the poor shaped he predicts the rock properties and the |
|
| 93:06 | thing that he said, he forget about everything that I wrote, |
|
| 93:11 | said, but really cos is the shape, that's the bottom line. |
|
| 93:16 | tell me what the poor shape that's the most significant. But it's |
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| 93:21 | something we can't describe very effectively. not easy to describe. So we |
|
| 93:29 | back to these other ones sitting right . OK. Stanford also gave us |
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| 93:36 | idea and I gave you a program do this and that is, can |
|
| 93:44 | predict velocity? Just knowing the porosity one location. What do you mean |
|
| 93:55 | that? You know that sandstone you looking at on your, well, |
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| 94:00 | had a velocity of 10,000 ft per and a proxy of 26%. What |
|
| 94:07 | the velocity be at capacity with the ? 30%? 22 2018? What |
|
| 94:13 | , what would the velocity be? I'm making predictions of what the velocity |
|
| 94:20 | be based on one data point. that source centers around Stanford saying you |
|
| 94:30 | two different curves that you're gonna get a sorting curve and a digenetic |
|
| 94:37 | The swing cur depends upon the depositional . And give me an example of |
|
| 94:46 | in the Deepwater Gulf of Mexico, have Turbos, they get down and |
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| 94:52 | off into the deep water or on slope, they cut channels. And |
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| 94:59 | you go ahead and look at the in that channel, you will see |
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| 95:04 | 32% porosity. And uh that's Sam go up to the levy and it |
|
| 95:11 | down to 28%. But the velocities almost identical. Why? Because the |
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| 95:21 | thing was the depth, the differential and the depositional environment. That is |
|
| 95:30 | of the trends that they define. I show you later on how to |
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| 95:34 | generate these with a lot of wells the meanwhile, if you wanna know |
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| 95:40 | this particular, well, I got porosity velocity. But what if I |
|
| 95:46 | shallower and deeper what are the velocities be? And that is a digenetic |
|
| 95:54 | and that's the cementation age consolidation. are what change? And there's a |
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| 96:01 | for that. And we give you of measuring that. Yes. |
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| 96:11 | I do. What? On back one, the pro I would think |
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| 96:31 | uh jail and they probably have number . OK. Um, let's |
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| 96:42 | I used to have another one in where I did this, in other |
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| 96:49 | , basic what, what normally it the cleaner, the sand, the |
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| 96:56 | the velocity. That's the normal the normal case. But I, |
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| 97:02 | was corrected in my thought by Doug when he went ahead and he made |
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| 97:09 | template for reservoir characterization and he had clean sand in the shell. And |
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| 97:16 | he says, if you start with clean sand and you add clay a |
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| 97:23 | bit of clay, it'll go to pores. If it goes to the |
|
| 97:28 | , it increases their moduli, it the rock. But at some time |
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| 97:35 | clay is now gonna be around the , the grain context. When that |
|
| 97:42 | , you weaken the marli of the . So you increase with more clay |
|
| 97:50 | and then each start decreasing it as add more clay. That's the philosophy |
|
| 97:55 | he was proposing on some of the that he built, we'll show that |
|
| 98:00 | on. So that's so, and other one is normally when you have |
|
| 98:07 | , the velocity goes down play. Sam? That's Wang's article I just |
|
| 98:16 | out Wang. You know, I no original plots. Hey, |
|
| 98:22 | Yes. Could you sorry. Go to that same slide. Can you |
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| 98:30 | the water and gas saturation one more ? Sorry. Yeah. Ok. |
|
| 98:37 | . This is a classic paper. one wri written. Well, let's |
|
| 98:44 | back a little bit. And the sixties people and Shell said that they |
|
| 98:55 | doing it in 66 according to Mike , they were finding bright spots which |
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| 99:05 | to gas sands and never see a events that had very large amplitudes whenever |
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| 99:13 | had saturated with gas. And at time, Shell along with Mobile to |
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| 99:19 | another big company BB brought back their in order to measure rock properties which |
|
| 99:29 | , they quit, they were losing that all came by the bright spot |
|
| 99:35 | was coming up and, and doing . Norm, Domenico reported on Amoco's |
|
| 99:44 | and what he pointed out is when add, when I have full water |
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| 99:52 | the sand, this is 100% When I have full water. The |
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| 99:57 | sits up here at 8000 ft per . When I add just a little |
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| 100:01 | of gas, my velocity drops quickly to about, I don't know, |
|
| 100:10 | 7000 from no 8000 maybe to And then it actually starts to |
|
| 100:20 | And the reason why is velocity is to the square root of K plus |
|
| 100:34 | thirds mu divided by the density. you add 5% yes. K and |
|
| 100:49 | are destroyed. Me doesn't really care the hell is in it for. |
|
| 100:54 | K, the Bach Mars, you've that and it's gonna stay low no |
|
| 100:59 | what other more gas you add, gonna be a, a low |
|
| 101:05 | It's ok. Decreases like this, quickly decreases the, and this is |
|
| 101:17 | going over, it quickly decreases. . The bulk matches quickly decreases a |
|
| 101:30 | bit of gas that added and then keeps going down. So that's the |
|
| 101:35 | value right there. Now, the this goes up like that is because |
|
| 101:42 | velocity is inversely related to the density the sand and the density is gonna |
|
| 101:49 | lighter as you put more and more in it. The sentence, that's |
|
| 101:53 | this goes up, the ball goes . Now that, that explains |
|
| 101:59 | the water saturation of the gas, here's a very important thing that that |
|
| 102:05 | . A lot of people didn't realize labs when you bring a sand into |
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| 102:12 | lab, they wanted to satisfy gas equation. So they go ahead and |
|
| 102:20 | dry the sand out and they start a little bit of gas, a |
|
| 102:25 | bit of gas, a little bit gap until it's fully gas saturated. |
|
| 102:29 | they take measurements along the curve and wasn't satisfying gas man's equation. Then |
|
| 102:35 | realized something when they dried it, took away the irreducible water. And |
|
| 102:43 | when they're adding a little bit, when they start adding gas, it |
|
| 102:50 | has to have irreducible water. At very beginning, you can't get rid |
|
| 102:56 | that water. That water is part the skeleton and that was the initial |
|
| 103:04 | . So now once they've done that Equation can predict this right here. |
|
| 103:12 | don't know if I satisfy everything you for. No, that was |
|
| 103:17 | Um Yeah, I guess I'm confused . You said like as you add |
|
| 103:23 | and more gas, the velocity goes because the density is coming down |
|
| 103:56 | Velocity equal to K plus four thirds over the density K as a function |
|
| 104:06 | gas, excuse me as a function water. Then to all gas, |
|
| 104:13 | goes like this, it drops down . Kay does the bulk modulus. |
|
| 104:23 | you just add a little bit of . You got this thing now basically |
|
| 104:28 | in that range. But the density going to linearly decrease as you add |
|
| 104:35 | and more gas. So you make a smaller number, the velocity |
|
| 104:41 | And this is why when we looked the velocity, it decreases like this |
|
| 104:46 | then starts up like that. And effect right here is the density |
|
| 104:55 | Gotcha. No, that makes Yeah, I guess it was counterintuitive |
|
| 104:59 | at the velocity versus the fluid I have some slides on that. |
|
| 105:04 | . No, that makes sense. . What time do we break? |
|
| 105:17 | it time to break? I forget is. We had a break an |
|
| 105:26 | ago. Somebody said, what's the score? What can't you make it |
|
| 105:36 | faster? Tell real. She's wins this money. Now, she's |
|
| 105:44 | let's take about a five minute Hey, group, you're there |
|
| 106:03 | Let's go ahead and squeeze rocks. to them cry. It's always worth |
|
| 106:09 | lot of fun. Velocity and poor . Wow, this goes back to |
|
| 106:19 | . In fact, this, this uh by Hixson Bery at Mobile |
|
| 106:26 | I actually knew Jim Berry. The were take a core and the core |
|
| 106:38 | that they had at 17.6 ferocity and and go ahead and start squeezing it |
|
| 106:59 | overhead. So over burn pressure, starts off with the velocity of about |
|
| 107:07 | say, and you add an extra next year 1000 P SI and it |
|
| 107:14 | from 10, 5 up to add another 2000 P SI, it |
|
| 107:21 | up to 12 5. So as can see a great increase of velocity |
|
| 107:27 | the initial squeezing of the core and it's coming along and it looks like |
|
| 107:32 | gonna flatten out eventually, something like . And these initial squeezing could be |
|
| 107:40 | of the micro cracks until you get to about 6000 P SI or something |
|
| 107:47 | that right here. And that's corresponds 6000 ft depth approximately overburden. But |
|
| 108:03 | the same time he did something you try to keep the, try |
|
| 108:10 | keep the differential pressure the same. is the overburden minus the poor, |
|
| 108:17 | try to keep that the same. so when you have 1000 P SI |
|
| 108:24 | here, you don't add any pore . And then when you go to |
|
| 108:29 | P SI, you had 1000 more added and so forth. So the |
|
| 108:35 | is always 1000 P SI between the four minus the poor three, overburden |
|
| 108:43 | the poor in the velocity is relatively . Are there any changes if we |
|
| 108:53 | it again? For all of these in here, you can see even |
|
| 109:01 | up to 5004 or 5, 6000 SI difference. Of course, as |
|
| 109:08 | go up in the difference increases by P SI, they're getting smaller velocity |
|
| 109:16 | . You're reaching an asymptotic where eventually gonna be one velocity quartz velocity. |
|
| 109:25 | differential pressure over by, by overburdened four. And then there's another one |
|
| 109:34 | became famous for some Amos Nora's work one of the it's affected pressure and |
|
| 109:40 | is overburdened minus N times the pore or N varies from 0 to |
|
| 109:50 | No, the effective stress coefficient is thought to be very close to |
|
| 110:00 | It's also very dang hard to use real life because of the complication, |
|
| 110:08 | measurements you gotta make not an easy to do. I had a young |
|
| 110:20 | who did the study trying to major and we did it with P wave |
|
| 110:29 | shear waves and it was a dynamic . And we told people we know |
|
| 110:38 | gonna get all upset, start screaming and rating because and is supposed to |
|
| 110:43 | done with static stress strain. I , we know that but we're getting |
|
| 110:48 | same functional relationship for the end that get. I said, I think |
|
| 110:53 | not worth noting. And so she a very good job and we'll show |
|
| 111:01 | of the re not, these aren't results as some we've done earlier, |
|
| 111:07 | wanted to go ahead and show some of effective pressure. So how are |
|
| 111:13 | gonna do that? I contacted six companies that were drilling in the deep |
|
| 111:20 | and they go from 1000 ft to ft water depth here. And I |
|
| 111:26 | , would you mind going on drilling and then when you get done, |
|
| 111:33 | sure you get a good log suit and density and all the curves and |
|
| 111:38 | them to me. Oh, sure anything for the University of Houston. |
|
| 111:44 | with that and he got all those girls, six different wells. And |
|
| 111:52 | I plotted the data and what you're at here is each interval. I |
|
| 111:58 | it's 2 2500 ft. Yeah, is 1 2 3 4 5 6 |
|
| 112:06 | 2500 ft is per interval and this 500 ft. Each one of these |
|
| 112:14 | is 500 ft. And in this ft interval, I took all the |
|
| 112:19 | logs and measured the interval velocity in particular depth range right here. And |
|
| 112:27 | plotted the velocities and the green the green data that represents the average |
|
| 112:40 | . And you can see that on average, this isn't bad if you |
|
| 112:45 | of a guy up here smoking a to say, OK. Other than |
|
| 112:52 | , I don't think this curve is effective as far as giving me advice |
|
| 112:59 | the deep water. In other if I said that year, if |
|
| 113:05 | at a depth of 8000 ft, my interval velocity of my sin likely |
|
| 113:13 | be? And you look at this and say, oh yeah, that's |
|
| 113:17 | to predict. Come on a big inversion, something's wrong here and even |
|
| 113:24 | density same way. So I did wrong. Oh I know I took |
|
| 113:32 | the sediment. I should have done by itself and shield by itself. |
|
| 113:39 | that's not the answer. The answer really should have examined it separately. |
|
| 113:47 | the answer is no answer is, do you use for a depth re |
|
| 113:54 | ? All these were plotted as a of sea level. And this is |
|
| 114:01 | important concept here when you're in deeper , how your velocity is gonna change |
|
| 114:10 | velocity should be referenced to ocean How deep are you beneath ocean |
|
| 114:16 | And when you do that, these the curves that you get. Take |
|
| 114:19 | same six suites of, well L look what happens when you use ocean |
|
| 114:25 | as a reference rather than sea level and day difference. I feel very |
|
| 114:32 | in using this curve and for predicting my interval velocity is gonna be, |
|
| 114:38 | almost a straight line curve that you're there. The density a little bit |
|
| 114:44 | straight line. But down here, think we're beginning to get into possibly |
|
| 114:52 | sitting down here, possibly. But this one section, it's a straight |
|
| 114:58 | that's a straight line and it's the effective pressure is equal, overburden |
|
| 115:11 | N times poor pressure. Say this way fred from everything that we see |
|
| 115:21 | here. This is called normal What that means is the overburden is |
|
| 115:31 | P si per foot. The pore is about 0.5 PC per foot. |
|
| 115:39 | there are some spots that are called pressure. Some spot in the Gulf |
|
| 115:45 | Mexico will all of a sudden, poor pressure becomes really high, high |
|
| 115:53 | that if you don't put a heavy mud, you'll blow the top off |
|
| 116:00 | the crown, the drilling crown and sink your platform. There are two |
|
| 116:07 | types of abnormal pressure which we will examples of. But when you only |
|
| 116:14 | data that's above the onset of geo , which is the onset of abnormal |
|
| 116:29 | . What is abnormal pressure? You hear of that abnormal pore pressure? |
|
| 116:40 | normal pressure? Normal pore pressure is get down to 13,000 ft. That |
|
| 116:52 | normal pore pressure if at 30 if water and the particular sand can escape |
|
| 117:00 | the surface just and not by going any shell, their fault by so |
|
| 117:07 | the pressure at th the water pressure 13,000 ft is the same if it |
|
| 117:14 | just a continuous column of water. the poor pressure at 13,000 ft would |
|
| 117:21 | one half of that 6500 P si the overburden would be 13,000 P si |
|
| 117:31 | £1 per square £1 per foot Now, abnormal pressure, it means |
|
| 117:40 | you go down to 13,000 ft, poor pressure is not gonna be 6500 |
|
| 117:47 | si, it could be 9000 B , it could be 3000 P si |
|
| 117:54 | you, you forgot about. You know about, well, 3000 P |
|
| 117:59 | doesn't sound like a big number until realize that's sufficient. That if |
|
| 118:07 | if it escapes and goes up the , it'll blow the rig hardly |
|
| 118:13 | It'll take all the pipe, shoot and mile in the air. It's |
|
| 118:18 | good air gun. Ok. why does that occur? Well, |
|
| 118:27 | think of two different mechanisms. One we call soft pressure and this |
|
| 118:42 | when you're in deep water, most the sediment comes from turbo light |
|
| 118:54 | sediment that comes off the shelf edge the slope and into the Epistle |
|
| 119:04 | And there's another turbo I flow on river meanders to another place. |
|
| 119:12 | look at that versus what happens on shelf. The Mississippi river comes up |
|
| 119:20 | a deltas form across the whole The sands are continuous, you can |
|
| 119:28 | it as continuous. So tite you can have a stand that only |
|
| 119:39 | a communication up and down that channel it has such a great chance not |
|
| 119:46 | be continuous. There won't be a path up to the surface. O |
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| 119:57 | would that happen? Well, let's off. Let's go ahead and deposit |
|
| 120:02 | Sam and a shell and a And all of a sudden there's a |
|
| 120:10 | storm. Another Katharina comes, was the name of that storm? Katrina |
|
| 120:21 | , Catherine is my granddaughter's name. storm comes and it dumps a big |
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| 120:30 | amount of material on top of this water deposit. And all of a |
|
| 120:38 | down around 4000 ft, you dump extra segment on it. And the |
|
| 120:45 | yells at stop. You put so pressure on me. My little tiny |
|
| 120:52 | that I have. You've closed I can't squirt any more water out |
|
| 120:58 | my sediment because you close them. don't have permeability at all. Not |
|
| 121:06 | the Nando. And you add more and it becomes tighter. Pretty soon |
|
| 121:14 | have a certain amount of water in shells. It stays that amount of |
|
| 121:20 | . It doesn't change. That water constant. So the amount of water |
|
| 121:26 | a shell is constant for thousands of , the overburden pressure minus the pork |
|
| 121:38 | stays the same. The effect of from when that shield, you know |
|
| 121:44 | I not permeable anymore all the way , you have a constant P wave |
|
| 121:51 | , it doesn't change. And some the deep waters wells, you will |
|
| 121:57 | 16,000 ft of almost the same P velocity won't change. Now, that |
|
| 122:05 | what we call a soft or another that they use is a oh an |
|
| 122:18 | . What was the first words? gonna appear here? Thats if I |
|
| 122:34 | s a compaction, this equilibrium that and we'll go back. So when |
|
| 122:48 | have a compaction, desig the shell the watering and it holds the same |
|
| 122:59 | of fluid from there all the way , then we'll go back and look |
|
| 123:03 | the pore pressure. There's another one the Smite. The ill light |
|
| 123:09 | Once you get in a depth range 8000 to 10,000 ft depth, the |
|
| 123:15 | and pressure come about to start the age of the kitchen to cook the |
|
| 123:21 | . But when it starts doing the smite starts losing some of its |
|
| 123:27 | and it starts, it starts to two layers of water rather than three |
|
| 123:33 | plates, something like that. The gets denser, it increases because its |
|
| 123:41 | of water j then all of a it reaches the point or any more |
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| 123:56 | from smack night to e life, poor can't handle it. They're not |
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| 124:06 | anymore. And so the, but poor pressure can build up very |
|
| 124:20 | And let me show you that with little diagrams, here is over burn |
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| 124:28 | , one P si per foot and goes down like that. Now here |
|
| 124:35 | how the static pressure, it's about half the P si per foot that |
|
| 124:42 | over burn. So this down at ft, it has a pressure. |
|
| 124:50 | poor pressure is 5000 B si. at this depth right here, I'm |
|
| 125:03 | say we have the onset of abnormal . Normal pressure is this blue line |
|
| 125:15 | . But now I said there's a here. And as the abnormal, |
|
| 125:21 | does that mean? That means this right here is this equilibrium. This |
|
| 125:30 | where the shale says I can't delete water anymore. So the difference between |
|
| 125:38 | overburden and this poor pressure coming about of this equilibrium, it's constant right |
|
| 125:49 | . It doesn't change ofd effective pressure change, the velocity doesn't change. |
|
| 126:01 | beneath the onset, you're getting this velocity for the this equilibrium compaction. |
|
| 126:12 | , at the same time, there's one right here. This is the |
|
| 126:17 | to light and what we note is effective pressure is this distance right here |
|
| 126:28 | the overbred and the poor. We over to velocity. And we know |
|
| 126:33 | put a velocity va call, call that affect the pressure that I have |
|
| 126:40 | here. That is the same as shallow. So if I know this |
|
| 126:48 | , if I know this effective pressure here, I can predict what the |
|
| 126:54 | is, but it goes the other around. You tell me what this |
|
| 126:58 | velocity is right here. And I'll you what the pressure is, the |
|
| 127:03 | of pressure. I know what the is. I can calculate it. |
|
| 127:07 | gonna determine this effective pressure by knowing velocity, I can go out in |
|
| 127:13 | area before I start and I will ahead and I will find an area |
|
| 127:19 | has a continuous always in normal Now, this onset of abnorm was |
|
| 127:27 | one area not in mine. I'll this right here up in the uh |
|
| 127:35 | apart on the shelf. So, now I have three different ways the |
|
| 127:45 | is gonna change. Did you ever of velocity analysis? Seismic processing? |
|
| 127:51 | you know you can get an idea the interval velocity is through seismic |
|
| 127:56 | Did you have a, do you that idea? Do you ever have |
|
| 128:01 | idea that maybe you'll be looking at data? Do you ever have the |
|
| 128:07 | that some time in your life? gonna be irresponsible to review this 3d |
|
| 128:12 | and geologically determine the best places to hydrog carbs. Is that a possibility |
|
| 128:18 | your life? So now we're gonna you a couple of things. One |
|
| 128:23 | when you order that seismic data and become manager, make sure you get |
|
| 128:30 | seismic data. What we're telling right is you wanna make sure that not |
|
| 128:36 | do you get the high quality migrated you want a volume of effective a |
|
| 128:45 | of interval velocity or R MS you want that volume. So you |
|
| 128:51 | determine where the onset of abnormal That's very important. Safety wise. |
|
| 128:58 | tells you the Strat gray tells you drilling hazard. It tells you what's |
|
| 129:03 | best chance where the hydrocarbons are. chance of getting gas is right above |
|
| 129:09 | top of the overburden pressure. The place it tells you if I have |
|
| 129:17 | particular status, which means it was smack t to ill light transformation. |
|
| 129:28 | effective pressure, if I wanna drill to there, my effective pressure right |
|
| 129:34 | here is very small. Meaning the pressure is very high. If you |
|
| 129:42 | ahead and you predict mud weight based hydrostatic and you drill down here, |
|
| 129:50 | gonna have this amount of poor pressure you don't account for. That's 3000 |
|
| 129:57 | SI that is bad news folks. so you wanna be able to predict |
|
| 130:02 | . Now, there are people that this for a living, the people |
|
| 130:06 | do this for a living like Ralph colleague. I know at school he |
|
| 130:11 | when I make a prediction, I to be at the drilling location all |
|
| 130:17 | time. I live on that. made the prediction. I gotta live |
|
| 130:21 | while they drill through it. And you wanna be sure because that's your |
|
| 130:29 | . Yo I thought you were getting . I got her to get one |
|
| 130:39 | again, compaction, disequilibrium or Smite L light. Transformation over burn pressure |
|
| 130:51 | £19.21 per gallon. One P, foot. How to sta it's not |
|
| 131:02 | it's 0.433 P si per foot and £8.3 per gallon. Did you ever |
|
| 131:12 | of the engineering system? Oh Can believe these units? £8 per gallon |
|
| 131:20 | uses pounds, whatever happened to what do they call the other uh |
|
| 131:28 | or something system like that? Sae who uses a volume of a |
|
| 131:42 | How would you, why do you mud weight? This is mud |
|
| 131:48 | A pos Brion, the gradient is as mud way. So this right |
|
| 131:55 | it's £8 per gallon. You're on rig and you ask one of the |
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| 132:03 | hands, take that gallon bucket, it out of the pit that you |
|
| 132:09 | with the mud and weigh it and get what the, you get the |
|
| 132:15 | way. 8.3. So at the beginning. That's how they measured mud |
|
| 132:21 | they just took over there. I know how much money put in |
|
| 132:24 | how heavy it is, how much rights in there nature. So you're |
|
| 132:31 | drill, you gotta select the mud . You select the £13 per |
|
| 132:36 | Good. It falls right in between two curves. And are there any |
|
| 132:46 | you might give? Yeah, there a couple you selected £13 per gallon |
|
| 132:51 | order to drill and it falls in these. Ok, at any level |
|
| 132:57 | in here, if the mud weight less than the pore pressure, the |
|
| 133:03 | fluids will flow into the mud. other words, if I happen to |
|
| 133:10 | coming down here and the onset of pressure and it goes like this, |
|
| 133:18 | is the poor pressure and this happens be the mud way that right there |
|
| 133:25 | less than this value here. So this depth, the amount of pressure |
|
| 133:31 | gonna be against the formation is less the mud way, meaning everything that's |
|
| 133:39 | the formation is gonna flow into the column and come out of the |
|
| 133:46 | So that's one of the things you against the other is you can't get |
|
| 133:51 | mud weight to be £20 because if get the mud weight to be £20 |
|
| 133:59 | that's heavier, then they form over pressure. So what that means is |
|
| 134:04 | the mud is gonna break into the and push the water out. So |
|
| 134:11 | don't want that to happen either. you're mud weight falls in between the |
|
| 134:18 | and the poor pressures. Now, difficulties, we're gonna drill a well |
|
| 134:25 | a deep water. And when we that, a little problem begins |
|
| 134:35 | I still use 0.5 overburden. One right here coming down in the dotted |
|
| 134:43 | . That is one P si per . If you drilled on land, |
|
| 134:48 | would be your hydrostatic pressure. I your over bird pressure. When you |
|
| 134:54 | in deep water, the drilling program this depth right here. What is |
|
| 135:03 | overburden pressure? The overburden pressure at depth right here is going to be |
|
| 135:13 | it's going to be? 3000, P si what is the more pressure |
|
| 135:28 | be? The pore pressure is gonna 3000 P si in the water? |
|
| 135:39 | overburden is water in the water. pore pressure is water. So that |
|
| 135:46 | at this depth right here, your pressure is equal to zero. That's |
|
| 135:54 | same as having you drilling into the . That's right at the surface. |
|
| 136:02 | don't have any water. So what's velocity right there? What do you |
|
| 136:13 | the velocity to be right at the ? You're 7000 ft depth. What |
|
| 136:20 | of interval velocity do you expect to ? 10,200 ft per second? So |
|
| 136:30 | you are 5200 ft per second. that's up shallow right here. But |
|
| 136:37 | it's time here because when you have up here, your effective pressure is |
|
| 136:43 | same as this, affect the pressure here because your overburdened is the same |
|
| 136:51 | your pore pressure. No, this line is superimposed over here and this |
|
| 137:01 | the overbred pressure. And let's look the drilling program. The drilling program |
|
| 137:12 | , I'm gonna drill down to about ft and I'm gonna drill with £8.32 |
|
| 137:23 | gallon. That's this blue line. , Fred, why don't you just |
|
| 137:28 | a little bit more? Go maybe . Well, if you go to |
|
| 137:34 | look what happens right at, right the surface there, you have mud |
|
| 137:42 | happens to be denser than the formation . That means you drill going slow |
|
| 137:48 | there. All your mud is gonna into the shallow beds. So you |
|
| 137:53 | through, you start here, you like heck this 1st 300 ft and |
|
| 137:59 | put a column down in there at chamber that might be thir 30 inches |
|
| 138:05 | diameter. And that's gonna be your seal, your upper uh pipe that |
|
| 138:11 | cement in to stop any of the flowing into the formation. It's very |
|
| 138:18 | at the very beginning because £8.3 you go over that by much and it's |
|
| 138:25 | start to flow on you. So , we in there basically blow away |
|
| 138:30 | shallow set of them, keeping air pressure on it and put the |
|
| 138:34 | up. Now it will get down say the 11,000 ft and at 11,000 |
|
| 138:41 | , we now hit a poor pressure all of a sudden you gotta have |
|
| 138:47 | mud. It's more than this But the problem is if you go |
|
| 138:55 | and put a mud that's bigger, going to go through the formation up |
|
| 139:03 | . So that means you come down , you gotta put a pipe all |
|
| 139:07 | way down to this pipe. Then the 13 lemon pods. You can |
|
| 139:14 | drilling until you get to maybe at location right in here. And what's |
|
| 139:21 | happen is at this, well, this location right here, you're gonna |
|
| 139:27 | to have a uh increase mud weight near the need to have a pipe |
|
| 139:35 | all the way down to here. the reason that they have four or |
|
| 139:44 | log runs is because they gotta lay down in order to protect them from |
|
| 139:51 | formation fluid coming into the pipe or versa. Breaking the formation service. |
|
| 140:09 | just wanna check to see if anybody's over there. I've lost everybody over |
|
| 140:15 | . Yeah. Yep. They're not , they don't even mind yawning against |
|
| 140:21 | other. But that's ok. I up with it. I've seen |
|
| 140:27 | I don't know when though, but did. No, that's ok. |
|
| 140:33 | just stand up take about a three four minute break. Now it's, |
|
| 140:38 | getting close to kickoff time. We're gonna pray, sit down and have |
|
| 140:44 | , a prayer session. Oh, know. You want doughnuts rather than |
|
| 141:06 | , right. Stop. How much do we have? Left? Five |
|
| 141:25 | ? Ok. Is that empty? just eating the wiener though. Just |
|
| 141:51 | the sausage. I'm not gonna go , but I don't know why I |
|
| 141:56 | that. I forgot that your cheese that squirt on stuff? Their |
|
| 142:07 | Yeah, that's, that's that Shipley on Scott Street. You know, |
|
| 142:36 | , uh, subway shop. Scarlett Street, I used to teach |
|
| 142:41 | night from 7 to 10 and I'd over there and get a subway for |
|
| 142:47 | day. This is a couple of . Things like this happen. One |
|
| 142:54 | a, walked in and the young behind it. Connor was all kind |
|
| 142:59 | nervous and, and I start to to her and put my order and |
|
| 143:04 | said there's something wrong. Are you ? She says, no, I |
|
| 143:08 | what she said, well, the , you, you just passed, |
|
| 143:10 | just got done robbing us with a and I passed him in the |
|
| 143:13 | So I was coming in there is time and then it became a hangout |
|
| 143:20 | the high schoolers and they used to up right by the door. |
|
| 143:29 | uh, I don't, what, would we call? They would make |
|
| 143:38 | of you or not joke with uh, taunt you as you're walking |
|
| 143:44 | the door. And these are all school kids and it was girls and |
|
| 143:50 | both. So they were trying to each other. You know, that |
|
| 143:55 | , that didn't, is it And then it was, the homeless |
|
| 144:03 | come in there and sit on the of the door, either side. |
|
| 144:11 | it seemed like it was like the folks that they got mainly me and |
|
| 144:15 | of the other guy and they would for money as if you gotta pay |
|
| 144:21 | . And what are you doing You gotta pay me, you |
|
| 144:25 | that quick play over there. I , they are. Oh, I |
|
| 144:43 | know. So how many cartridges we left? Where are they from? |
|
| 145:30 | they from? B are they from six? Only two doughnuts left? |
|
| 145:36 | not bad. Those clutches suck Ok, folks, everybody's back. |
|
| 146:12 | want to remind you a little bit this drilling program and what happens at |
|
| 146:25 | onset of abnormal pressure. This dotted here that happens to be this equilibrium |
|
| 146:40 | . And this other one is smack to L light transformation. This is |
|
| 146:46 | the shelf. This is the deeper off the slope. But then show |
|
| 146:54 | if you're drilling with £8 per gallon so along here and you run |
|
| 147:03 | continue dumb. And if it's this pressure here, what is sure one |
|
| 147:10 | off the shop. It's very You miss, you miss it just |
|
| 147:15 | a little bit. So if you're with £9 you can increase it to |
|
| 147:22 | . 10 and not worry. But it's this right here, big |
|
| 147:27 | quick change, there's places where you from 10 to £16 almost immediately because |
|
| 147:35 | how much that poor pressure increases in to overcome the effect. Now, |
|
| 147:42 | that in mind, we're gonna look drilling in the Gulf of Mexico and |
|
| 147:52 | are about 17,000 wells that we have a database that we've edited and pretty |
|
| 148:02 | made it ready to make maps. instance, if you wanted to make |
|
| 148:08 | map of the interval velocity of sand seven and 8000 ft, you could |
|
| 148:15 | ask for that and it would happen a matter of four or five minutes |
|
| 148:21 | or if you wanted the interval velocity shale over that same thing or the |
|
| 148:26 | , certain grip or map where the were the hard, the uh or |
|
| 148:35 | A vo response might vary particular how it varies. You can make |
|
| 148:41 | these maps and we, I've done with students where we just come out |
|
| 148:45 | this and we have the patio and logs and we just come in here |
|
| 148:52 | correlate and make predictions of what happens all these well logs as far as |
|
| 148:57 | A bo response, their seismic response and without hydrocarbons. If I take |
|
| 149:07 | line north to south like this, the southern part, right here in |
|
| 149:15 | northern part on this side. Over , up here, I can drill |
|
| 149:22 | to 14,000 ft and be in normal and at 14,000 ft, I'm gonna |
|
| 149:33 | the smite to ill light transformation. , down south here at 4000 |
|
| 149:44 | I'm gonna have a compaction. This occur and my abnormal pressure starts right |
|
| 149:52 | at 4000 ft. This is to smite to the light. And this |
|
| 149:59 | in here is it disequilibrium compaction. ? Up here in this region |
|
| 150:10 | you are looking at a patio self right here. And that means this |
|
| 150:18 | all deltaic sense. You can map when you try to map the sands |
|
| 150:25 | below, they're not continuous. You're at turb light flows. So actually |
|
| 150:32 | a map is not correct. It mean a lot because the turb light |
|
| 150:38 | are individual and they're sparse going around . But at the same time, |
|
| 150:44 | delta means that you have a means the shield when it's compressed to send |
|
| 150:54 | water up to the surface of ocean . Down here, you have mainly |
|
| 151:03 | lights, you're off the shelf And so by the time you get |
|
| 151:08 | 4000 ft, you're squeezing shill and no sand to put it where to |
|
| 151:14 | and it's the shells impermeable. You here you can get quote impermeable |
|
| 151:21 | but you're right beside the sand and sand is gonna allow that water to |
|
| 151:26 | to the surface not done on this . When you hit the abnormal pressure |
|
| 151:35 | , it is big. You have have a lot of extra mud. |
|
| 151:39 | you hit it here, it's not bad. Now, here's what it |
|
| 151:44 | like. The logs look like. is a soft concept. So right |
|
| 151:55 | , I am gonna look at something this area right in here. And |
|
| 152:03 | I take one will the velocity increases much straight line down to about the |
|
| 152:10 | of abnormal pressure. The density kind keeps a straight line down to the |
|
| 152:17 | of abnormal pressure and the initial mud is 10 to 12.4. But now |
|
| 152:25 | interesting thing, the density remains constant the way down, velocity remains constant |
|
| 152:34 | the way down. There's no change the fun because the effect of pressure |
|
| 152:40 | not change as we showed you in previous slides. However, the hard |
|
| 152:50 | that is up in this area right here, that is where you go |
|
| 152:56 | 14,000 ft. It's smite to ill transformation. And you can see what |
|
| 153:08 | . You go from £10 to £16 almost immediately. You velocity increases is |
|
| 153:17 | function of depth linearly till you hit abnormal pressure. And then look what |
|
| 153:23 | . The velocity decreases tremendously. That the effect of pressure has been changed |
|
| 153:31 | and that's where you need a quick of mud really fast. But an |
|
| 153:39 | thing that happens is look at the right here. The rock keeps getting |
|
| 153:44 | dense as we go down here. that's BECA and these are, |
|
| 153:49 | these are shells sitting in here because we can get rid of the water |
|
| 153:57 | in there. Interesting scenario. You're . You're getting more dense sales. |
|
| 154:05 | exercises. Now we're gonna go to who wants to be a millionaire candidate |
|
| 154:21 | she's gonna try to win you some money and you might wanna help |
|
| 154:27 | then you might not to see how has to squirm back and forth trying |
|
| 154:33 | make it answer this crazy question. here's the crazy question at point A |
|
| 154:45 | here. I find out that my velocity is 750 fee per second. |
|
| 154:55 | at 5000 ft depth over here at B, I'm at 11,000 ft and |
|
| 155:04 | velocity is 5300 ft per second. question is, how can you be |
|
| 155:13 | as deep? And the velocity is thirds. Why the poor pressure, |
|
| 155:24 | overburden is 4500 P. Si the here is greater 6000 and yet the |
|
| 155:34 | is less. So we have our who represents the entire department of eas |
|
| 155:47 | funding for the next five years. coming up with an answer. Now |
|
| 155:55 | might, she lost the candidate. lost the ability to ask the audience |
|
| 156:02 | she could, has to decide what do. Does anybody wanna try to |
|
| 156:11 | her uh why this occurs? Well, you're gonna have to give |
|
| 156:22 | , give me some numbers so I write it down. Tell me what |
|
| 156:25 | write, done. OK. Well, tell me you mentioned, |
|
| 156:39 | , what should, what should I down? You're, you're on the |
|
| 156:52 | what governs interval velocity in these unconsolidated ? That's half of it. What |
|
| 157:07 | the velocity? Remember it, it's poor pressure and it's not overburdened. |
|
| 157:14 | ? What? No, not effective pressure and what does affect the |
|
| 157:21 | ? Eagle? It's equal to the , man. It's the poor pressure |
|
| 157:32 | now. I gave you the overbred here. What's the poor pressure? |
|
| 158:04 | see you don't have this paint? you, do you have this |
|
| 158:08 | You do have a OK. Then out it's the effect of pressure and |
|
| 158:20 | equal to the overburden minus the I told you what the overburden was |
|
| 158:30 | P. Si now your 5000 ft . Well, it's the poor |
|
| 158:40 | half a pound for each foot. the pore pressure is going to be |
|
| 158:47 | P si there's no abnormal pressure on at all over here. Your 11,000 |
|
| 158:55 | depth, half of that 5500 P , we find out that the effect |
|
| 159:01 | pressure on this night is 2000 P over here it's 500 P si. |
|
| 159:11 | we find out that this over here a much deeper, much deeper |
|
| 159:20 | Pressure. You wanna solve that than here? OK. No real said |
|
| 159:32 | , she's surviving. She claims she's a good, good standing for the |
|
| 159:37 | . She's holding her head up high around saying that she wanted me to |
|
| 159:42 | how many zeros behind that number. is gonna win. I haven't told |
|
| 159:48 | yet. She might get excited. her too quickly, depositional environment, |
|
| 159:59 | effect on rock properties. It's a idea. Let's see what the depositional |
|
| 160:07 | will have for a base analysis. I bet that they don't put in |
|
| 160:13 | basic analysis. Is anybody doing the analysis, sir? You are. |
|
| 160:22 | , you help me out if you this. OK. What's that? |
|
| 160:32 | , I don't, I don't know a basic analysis is. This is |
|
| 160:37 | some information. Maybe it helps is wells and each 6000 wells you can |
|
| 160:47 | 200 ft intervals. So every 200 60 m, you're looking at 60 |
|
| 160:55 | 70 different attributes, things like velocity for shall the percentage of shall |
|
| 161:02 | samp the thickness of the sham normal values, etc velocity, gas, |
|
| 161:13 | saturation. So let's look at this picture if you ask for the same |
|
| 161:23 | from three th does anybody ever has heard of the Gulf of Mexico? |
|
| 161:29 | OK. Everybody there. He heard the Gulf of Mexico? Yeah. |
|
| 161:38 | , good. So at a depth 3000 to 4000 ft, we ask |
|
| 161:48 | the same percentage and the areas that the hot pink are 70% sand sitting |
|
| 162:00 | there. No, this is New Orleans. That's about 303 150 |
|
| 162:08 | as the crow flies straight. Anybody an idea what this is right |
|
| 162:23 | Is this where Padre Island would That's the barrier island. No Potter |
|
| 162:28 | for the island. Ok. So high san percentage sitting there. Now |
|
| 162:35 | here, you got a blob of energy there, blob there, another |
|
| 162:41 | sitting over there. If I look this, this line right here actually |
|
| 162:52 | Texas from Louisiana or it might be up there. But what I find |
|
| 162:59 | interesting is look at this separation It looks like the Mississippi River came |
|
| 163:08 | blob, this out, moved and down blob that big sand out at |
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| 163:14 | location right there. But overall the to 60% sand sits there at 3000 |
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| 163:24 | 5000 ft. No, if I major sand deposit, what is happening |
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| 163:36 | here? We had, somebody knows the Bear Island sitting in there. |
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| 163:41 | wanna ask you for a little bit . This is the 5 to 6000 |
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| 163:45 | depth. And again, we have hi the percentage of sand and again |
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| 163:54 | over here. Now going on land we, we can do this 3 |
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| 163:59 | 44 to 55 to 66 to 7 the way down to about 12,000 |
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| 164:04 | I don't know if that would Maybe that would help make a map |
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| 164:08 | something that would not for writing a , getting some work done that the |
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| 164:14 | is available for use. But you notice the Shell ridge that's sitting in |
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| 164:23 | , that few wells are jeweled in . I wonder why it's all shale |
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| 164:28 | these depths. So we have a energy, they'll take deposits and then |
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| 164:37 | have these longshore low energy and the sort of as a watershed. It's |
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| 164:49 | half of the United States. over here in Texas, when we |
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| 164:55 | 45 different rivers that offer sand over 4/5 of Texas watershed. Not very |
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| 165:07 | , maybe I'm wrong. But in analyzing this, we decided that we |
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| 165:15 | two different depositional environments and so kind cutting it right there saying that's one |
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| 165:22 | one side from the Mississippi and these the five rivers or so from |
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| 165:30 | Now, let's look at the depth 7 to 8000 ft and the same |
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| 165:39 | , very high sand percentage sitting in . And what rock properties will be |
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| 165:46 | by this high S A percentage pros one. So let's look at shale |
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| 165:57 | sand, the velocities. Do you any difference in the velocities at 7 |
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| 166:03 | 8000 ft being sand and shell. much, they all seem to have |
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| 166:10 | the same philosophy as Dan Dui. what about density? Now, when |
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| 166:16 | look at density something strange comes out here, you have a definite break |
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| 166:27 | dense material, not so dense. the other side, it's definitely different |
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| 166:35 | what you're seeing for sand sitting in . And why is that? Let's |
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| 166:42 | if the poor pressure is related, I look at the share percentage at |
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| 166:52 | abnormal pressures. So here's a depth to 7 to 8000 ft and at |
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| 166:58 | to 8000 ft, I'm showing you sand percentage. This red line is |
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| 167:06 | the onset of abnormal pressure would occur 8000 ft. Notice that that abnormal |
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| 167:15 | line, everything to the north. high sand to the south, not |
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| 167:21 | sam. It's like this is a shelf eggs sitting in there with the |
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| 167:29 | to debate again, what else is ? Let's look at the density. |
|
| 167:41 | is the same 8000 ft abnormal pressure and look at the density. You |
|
| 167:46 | more dense material on the north side on the south side. Well, |
|
| 167:53 | ? Because this is still sitting inside pressure, the shells are getting |
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| 168:02 | they're leaking on the south side. shells can't leak because during that abnormal |
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| 168:10 | zone that, that discontinuous, that's disequilibrium uh compaction. There's no path |
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| 168:19 | the shells to dewater. So you shells that dewatered sitting on that |
|
| 168:30 | Now, does this affect gravity? mean, this is a significant density |
|
| 168:35 | if you look at the gravity map the SCG, you get some interesting |
|
| 168:41 | and that each one of these cyan represents five milligal. Did anybody ever |
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| 168:54 | of Pierce Junction? Anybody ever hear Main Street in Houston? Anybody ever |
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| 169:00 | of the Ashler Dome? Ok. Main Street by the Astrodome is the |
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| 169:06 | Junction. And if you go across first junction with the Vermeer, you're |
|
| 169:14 | see a 15 milligal contour. This 15 milligal. So these contours representing |
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| 169:22 | like a continuous salt ridge or salt sitting in there. And people |
|
| 169:32 | yeah, that's where the salt came , right? That's why you're seeing |
|
| 169:36 | . Ah But guess what, what these, these gravity contours also correspond |
|
| 169:43 | ? If I take the density I get these same contours don't even |
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| 169:50 | anything. It's nothing but a density brought about by the abnormal pressure. |
|
| 169:58 | they take that into consideration? they ignore it, brought it to |
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| 170:02 | attention but they ignore it. You have, when you do the gravity |
|
| 170:09 | , you have to take in consideration there is a place where the density |
|
| 170:13 | the sediments is significantly different above a line. And what does it |
|
| 170:19 | It follows the lines of the abnormal sitting in there. Major portions, |
|
| 170:27 | anomaly is density variation along along patio edge. It is not related to |
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| 170:35 | salt movement that a lot of folks suspect in the Gulf of Mexico. |
|
| 170:42 | seismic folks is gravity data better for major sand deposits, shell notoriously more |
|
| 170:55 | than Sam. We'll see it actually on that. So here is a |
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| 171:03 | percentage map versus gravity. These are high sand percentage, it's 7 to |
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| 171:10 | ft. And here you have a gravity anomaly low and low. |
|
| 171:18 | guess where the high is major shell in here, the low major sand |
|
| 171:25 | , the low major sin deposit. we have high and low associated with |
|
| 171:32 | , enormous major deposit, maybe gravity to be re evaluated for its application |
|
| 171:42 | basic analysis. But not before you your interval velocity to try to find |
|
| 171:57 | is where are the onsets of abnormal . So the regional relationship of depositional |
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| 172:09 | to rock property has been illustrated. about rock properties at the prospect? |
|
| 172:17 | you ever looked at those? Here three different curves. I want you |
|
| 172:27 | look at this green curve was derived probably around 2 to 300 wells and |
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| 172:39 | was measured in abnormal pressure of the . So if you go ahead and |
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| 172:45 | using this well, whenever we find pressure which tell the program stop. |
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| 172:52 | it's to be applied, abnormal pressure , stop. So the world gets |
|
| 172:55 | new depth, the new depth would the onset of abnormal pressure. The |
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| 173:00 | properties above that would be used. here is the velocity when you're in |
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| 173:05 | pressure is a function of depth. , this was an interesting one. |
|
| 173:11 | trend, did you hear right This is the trend in clay rich |
|
| 173:20 | and this is for regional analysis. of these are both these are taken |
|
| 173:25 | hundreds of wells. Now, the curve, the green, the not |
|
| 173:32 | green cur the S and curve. I'm going to follow this lines. |
|
| 173:43 | Cyan curve comes ahead and it says you get in the gear pressure, |
|
| 173:51 | coming here pretty much a constant velocity that velocity goes down until it reaches |
|
| 173:58 | clay which shall regional trend and that stays put at that particular trend right |
|
| 174:08 | . So it's saying that there are of the fast and slow velocity, |
|
| 174:16 | least we see for the shell sitting here. And it also gives us |
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| 174:21 | idea on is it clay rich or type of a shell sitting in |
|
| 174:32 | OK. Everybody's leaning back saying I it, Fred. Well, not |
|
| 174:41 | . Now, we're gonna take a at this area here and I'm gonna |
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| 174:46 | you, you have just discovered a spot at that depth right there and |
|
| 174:55 | bright spot means you got gas in in your formation. So you got |
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| 175:01 | in that formation. But the question , do you have the seal capacity |
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| 175:09 | keep that gas in there. In words, if you look at the |
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| 175:14 | of gas, is that integrity of seal still exist? Very important question |
|
| 175:26 | in this particular area, this is this equilibrium compaction. This is the |
|
| 175:35 | where the shell cried out and don't put any more on me. |
|
| 175:40 | can't stand anymore. I'm gonna start leak and then it became a permeable |
|
| 175:46 | that shall now you're going in and gas in it, pumping up the |
|
| 175:52 | pressure. Did it break the Do you still have a good res |
|
| 175:58 | has gas come out of that? you're just looking at residual saturation, |
|
| 176:04 | gonna be there forever. So a little summary, the effect of |
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| 176:19 | , the forgotten parameter. And I think we pay a lot of |
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| 176:26 | to these new seismic attributes that we generate mathematically without putting enough geological concentration |
|
| 176:36 | it. And that you as that's where you come in. |
|
| 176:41 | you have to take these different components say we need to consider this. |
|
| 176:48 | , you're getting all this inversion and getting a lower high one. But |
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| 176:52 | does it mean? I think we to expand the attributes. They could |
|
| 176:59 | have done this to your seismic Now, one of the things that |
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| 177:05 | find out about the affect of it, it controls Strat gray. |
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| 177:12 | noticed that if you're above the effect pressure, you have sand if you |
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| 177:18 | , you got more shall and we'll that over and over again. This |
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| 177:24 | the Zilka example, made money. components. The hydrocarbon system are affected |
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| 177:33 | effect of pressure. Your drilling program effective, your ability to predict poor |
|
| 177:39 | and mythology depends upon, are you a abnormal pressure or normal pressure? |
|
| 177:47 | other is when you're doing an you wanna display abnormal pressure horizon on |
|
| 177:56 | interval velocity section. This is call it stacking velocity. And this |
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| 178:19 | a sort of an old type of approach. And this is depth or |
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| 178:26 | going out here and you have these and what we do, we got |
|
| 178:48 | straight line coming down here and we a straight line coming right in here |
|
| 178:54 | these are the big contours and right , that's the onset normally of abnormal |
|
| 179:02 | . That's a point that you can map you got all your control where |
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| 179:11 | fif 50 CD PS you'll have a that you can find from your velocity |
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| 179:20 | , your velocity profile and contour that data is available if you ask for |
|
| 179:29 | . OK. Any comments there, time do we break? We break |
|
| 179:41 | ? OK. I lost my people the other room. Oh, there |
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| 179:48 | are. OK. People. I one of you basic but see |
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| 180:01 | think so something that, who did see that email? I bet you |
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| 180:11 | she's watching the football game. You're gonna tell me she had an appointment |
|
| 180:17 | Saturday during my class. Ok. the score? Anybody know what is |
|
| 180:29 | ? 30? Who's ahead? Raymond ? 30. Why don't you change |
|
| 180:36 | then? Lie to me. Make feel good. We know you're watching |
|
| 180:44 | over here. Hey, how are ? Yeah. How's CJ do so |
|
| 180:54 | ? I got it on TV right . I, I haven't really been |
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| 180:56 | it. Yeah. What do you ? CJ? Or Freddy? |
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| 181:02 | What's that? Freddie baby? Pre day, all day, all |
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| 181:09 | all night, do that or go the bar, right? I forgot |
|
| 184:03 | have to stop the share to get to another powerpoint. How much change |
|
| 184:13 | ? You don't need to stop I share your II, I don't |
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| 184:21 | how to change. I click. . How do I get out of |
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| 184:26 | powerpoint? You know, we and exc Oh, ok. I |
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| 184:33 | Click that and you. Yeah. . Thank you. Ok. Uh |
|
| 185:12 | lady from Pakistan. This next one for you because it was your country |
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| 185:19 | did this. I don't know how years ago. Maybe you can see |
|
| 185:30 | . Uh Can you read that that comes from Pakistan? Now, this |
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| 186:15 | have been in the western Pakistan, I think it reached the eastern Pakistan |
|
| 186:22 | . I can't hear you. you're thinking, you know the |
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| 186:46 | I had him put into my house . You get too complicated. |
|
| 186:59 | So it's ok here, Del Rio says, oh, it's so |
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| 187:04 | Ok. How obvious is this Del Rio? Take it now? |
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| 187:08 | at it. If you don't remove , you don't have any socks to |
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| 187:47 | . Are you there folks over What you keep saying? You don't |
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| 187:55 | to remove any but you won't have socks to wear, you gotta remove |
|
| 188:04 | . So how many do you Just, uh, aren't these embarrassing |
|
| 188:21 | ? What's that? No. we got group discussions going on. |
|
| 188:42 | noticed the young lady isn't so quick respond this time. Sorry, we |
|
| 188:51 | have. Ok. 20 brown 20 gray socks. Who has an |
|
| 189:04 | ? Ok. Ronald Reid. Give a color, brown or gray? |
|
| 189:14 | brown or gray, right? Two , right? So, all you |
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| 189:21 | to do was remove two, Oh, what do you want for |
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| 189:25 | second? What if the second time were moved to gray? So, |
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| 189:34 | you have to, you have to least go two times now take a |
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| 189:40 | stop, no matter if it's brown gray, you got a pair. |
|
| 189:46 | , it's only three. You only three. and you're gonna have a |
|
| 190:01 | that, ok. No. Did give you the missing dollar? |
|
| 190:21 | You have to have, you have take something home as a, an |
|
| 190:29 | and here it is. You I can guarantee you. This is |
|
| 190:33 | very, very difficult problem. I taking that seriously. If you have |
|
| 190:40 | 12 year old, ask them to you cause they can. And let's |
|
| 190:46 | at what the question is. Three go into a pub, they drink |
|
| 190:54 | . Their bill is $30. Each the writers $10 for a total of |
|
| 191:02 | . The bartender tells the waitress, charge them $5 too much and gives |
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| 191:07 | waitress 5 $1 bills. It's difficult divide $5 between three men. So |
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| 191:14 | waitress puts $2 in your back pocket gives each man $1 back. Now |
|
| 191:21 | is paid $9. Total. It , total it up. The three |
|
| 191:26 | have paid three times nine. That's and the waitress has two in her |
|
| 191:30 | pocket for sum of $29. The men went into the pub with |
|
| 191:36 | Now they can only account for Where's the missing dollar? No, |
|
| 191:47 | you try telling me missing are you , oh, it's just simple. |
|
| 191:52 | right here. No, you gotta it. You gotta prove it |
|
| 191:56 | Like telling how it sums up By the way, it is a |
|
| 192:15 | . I led you. Astray. says she thinks she has it. |
|
| 192:45 | , ok, that's your homework And by the way, this is |
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| 192:54 | trivial because if you tell it the I told it, it's gonna be |
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| 192:59 | difficult except I, I've, I've only a few people that it actually |
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| 193:07 | that right out. OK. Let's on to another topic. OK. |
|
| 193:36 | density models here are some empirical a velocity density models. A lot of |
|
| 193:53 | you need a density log. If are trying to go ahead and make |
|
| 194:01 | estimate of porosity, you always want density law. If you're trying to |
|
| 194:07 | a synthetic seismo gram, you're trying see how the amplitude might vary with |
|
| 194:13 | . You need a density log a of times if this is the second |
|
| 194:21 | third, well, in the they will not measure a density |
|
| 194:27 | initial log run. The density log a slower run time, slower |
|
| 194:34 | takes more time. So the original run might have something like a sonic |
|
| 194:41 | s speed. Then if there's hydro , they think they need it, |
|
| 194:48 | might run the density log. So lot of times you don't evidently law |
|
| 194:56 | you're gonna have to predict it. are five different ways and there are |
|
| 195:01 | than this, but just five ways uh you can do it. Some |
|
| 195:07 | these are empirical. The first one gathers everybody's attention is the one from |
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| 195:17 | Gardner. And that came out and about 1974 but he actually presented it |
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| 195:24 | uh a conference in 1969. And he got done looking at these, |
|
| 195:30 | said overhaul, all these lithos tend fit the curve density is equal to |
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| 195:39 | velocity to the quarter power. almost, except for a couple. |
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| 195:46 | instance, Jerry said the next time invent rock salt, they gotta make |
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| 195:54 | more dense. It's just too Now in hydra, that dude is |
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| 196:00 | heavy, he should be lighter and whole world will be much happier and |
|
| 196:06 | can use this equation. Well, quite. So John Castagna, he |
|
| 196:14 | ahead while he was at Arco and research team, they did a lot |
|
| 196:17 | good work there, by the um they had a bunch of data |
|
| 196:24 | around and so they plotted it up the open values here or shall. |
|
| 196:34 | these right over here are sandstones sitting . And overall Gardner's equation here that |
|
| 196:46 | lime fits the data pretty good, it doesn't fit the shale or the |
|
| 196:54 | very well just on the average. here's one for the shale, it |
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| 197:01 | of fits these data points and here's for the Sam fitting his data |
|
| 197:07 | So you have an equation where it's similar to what Gardner says. But |
|
| 197:16 | but it requires more than just the . It requires the lithology to be |
|
| 197:24 | also. So I'm going to make estimate of the sand density from the |
|
| 197:30 | in sand. And here's my transform he uses. Now, is it |
|
| 197:35 | ? Let me show you why it be important. You don't have a |
|
| 197:39 | low boss says too expensive, we need it next month. Boss wants |
|
| 197:46 | do a dry hole analysis and guess ? You gotta do it and you |
|
| 197:52 | have a density law and he wants to be quantitative. So you're gonna |
|
| 197:56 | quote amplitude variations with offset to make a quantitative interpretation. So you try |
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| 198:03 | say, oh, let's just use method of estimating a density level and |
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| 198:10 | come up here at 10,000 ft per and you say, OK, that |
|
| 198:15 | be my estimate. That's what the log, it's at 10,000 ft per |
|
| 198:20 | . And by using Jerry's code right , you'd come up with 21% |
|
| 198:26 | Now, if you used the sand right here, 10,000 ft per second |
|
| 198:32 | save 27% velocity. And guess what you use 21% versus 27% you're in |
|
| 198:43 | we call a different a VO You go from amplitude decreasing with offset |
|
| 198:49 | amplitude increasing with offset totally different It all have the same P wave |
|
| 198:56 | , but you had to estimate density it doesn't do a very good |
|
| 199:01 | So you have to have the lithology are the remaining relationships for other lithology |
|
| 199:13 | uh Arco published. And I would you though, when you get into |
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| 199:21 | area that you have small reflection do your own, do your own |
|
| 199:29 | get your own coefficients like the 0.22 . Because I think John said his |
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| 199:37 | said it's OK to publish it, don't publish the correct results. So |
|
| 199:44 | be suspect and do your own type a transform in an area, take |
|
| 199:48 | or six wells and this plot the and the density and make it fit |
|
| 199:54 | type of a curve. Do it Excel very easily. There's always Wally's |
|
| 200:01 | average equation and he gave us this in here. That's another lead. |
|
| 200:09 | this actually comes from a more than equation up here where you break the |
|
| 200:19 | saturation into our water and all solid . It's they did more than |
|
| 200:27 | One of the things though, every often we see people trying to use |
|
| 200:31 | form of this equation form of that adding hydrocarbons in there. And that's |
|
| 200:39 | misconceived in other delta team for the chromosome. It's just really wild |
|
| 200:51 | So that was, that was the the Castalia Wiley method. Here's Han's |
|
| 201:04 | method and Han's data 1986 his phd , he probably contains a data set |
|
| 201:15 | more scientists have used in order to their mathematical equation anybody else. And |
|
| 201:26 | I got done reading it and some the others, they said, oh |
|
| 201:31 | , sometimes it's not the numbers that get. It's the results that you |
|
| 201:37 | and what they mean on a general of analysis. And let me explain |
|
| 201:44 | a had 75 well consolidated sandstones, 10 of them were very clean no |
|
| 201:54 | . And there. And so he a suite of equations where we got |
|
| 201:59 | wave velocity is a function of porosity 10 sands. Then he got the |
|
| 202:04 | wave velocity is a function of porosity volume of clay. So we can |
|
| 202:11 | in order to see how the clean differ from the sands that might have |
|
| 202:18 | little bit of clay. And here is the results that we got on |
|
| 202:28 | and clay content is on the X . So zero means a very clean |
|
| 202:36 | and there it is purple and a is sitting on a measurement or this |
|
| 202:43 | a reduced or predictive. So divided by the actual measure is this |
|
| 202:51 | right here. And what you see prediction is off consistently. And it |
|
| 203:01 | whenever you get a clean sand, predicted velocity is a little bit too |
|
| 203:08 | . It should be actually more than . No, let's think about what |
|
| 203:15 | meant. If I have a, I have sand grains, I here's |
|
| 203:25 | model of my sand, by the , sand grain A san gran |
|
| 203:32 | there's no clay in here. And gonna talk about like the sheer |
|
| 203:40 | you send the sheer wave and it to this screen when you try to |
|
| 203:46 | sideways, ouch your scratch against scratch no claim here, but just add |
|
| 203:52 | little bit of clay. There it a little bit of clay. Put |
|
| 203:56 | grains of sand now, just go it slips immediately. A little bit |
|
| 204:02 | clay goes a long way from making grains slip. Now, do it |
|
| 204:10 | way. I had the grains sitting here. What if I put them |
|
| 204:14 | by side like this? Put a clay in there. Now, I'll |
|
| 204:17 | the P wave down. Guess what slide this way. So you get |
|
| 204:24 | sliding against one another very easily. you put just a little bit of |
|
| 204:30 | , you put a lot more It doesn't make a difference. You |
|
| 204:34 | your slippage already sitting in here. like a little bit of gas goes |
|
| 204:39 | a long way for changing the P velocity. And that was the first |
|
| 204:47 | this I ever saw a good explanation clean sands invariably show Avio normally that |
|
| 204:58 | harder carbs, they give a bright and a poison ratio is low and |
|
| 205:04 | exactly what this experiment showed. so bottom line, let's just read |
|
| 205:14 | the results would show a small fraction clay and the clean sand increases the |
|
| 205:22 | ratio significantly. So if you're a sand down in here and you add |
|
| 205:28 | little bit of clay, whoops, goes up on this line and this |
|
| 205:32 | poison's ratio. It, but when have a clean sound, a shale |
|
| 205:42 | clean sand has a big difference in ratio. But a shell over your |
|
| 205:48 | sands has some clay in it. doesn't change as much. So you |
|
| 205:53 | a big change in poisons ratio. that the second term Fred in your |
|
| 205:59 | simple Avio equation reflectivity is equal to and cosine squared plus poisons reflectivity time |
|
| 206:10 | script big change in Poisson's ratio, change in the farm offset and that |
|
| 206:16 | with very clean sand. So we God for give us that insight. |
|
| 206:27 | Horn has good insight. He said Sam. He allows me to make |
|
| 206:34 | which is nice. The Shirley sand they have that very simple reflection |
|
| 206:40 | it says that the change in poisons for the Shirley sand was 0.14 for |
|
| 206:48 | clean sand. It's almost twice the , meaning that as you go with |
|
| 206:54 | this value here, subtraction is gonna big compared much bigger, almost twice |
|
| 207:01 | effect, the one above it G . My goddamn company, no Geophysical |
|
| 207:13 | Corporation. That was my company that these data logs analysis. Here is |
|
| 207:28 | P wave in density. The sand shell, probably two or 300 wells |
|
| 207:35 | used here and this is the trend a lot of folks used to talk |
|
| 207:42 | this point right here and that says the crossover depth. We wet sand |
|
| 207:49 | , that's the blue becomes faster than shell. So if I have sand |
|
| 208:00 | shell, if I'm up shallow sand shell sand is slower, so you're |
|
| 208:12 | shale minus. Yeah. So this gonna be a plus reflection. If |
|
| 208:18 | shield has a, that's gonna be minus reflection. Yeah, shell has |
|
| 208:27 | lower value. So shall, shall sand of the minus reflection here. |
|
| 208:38 | plus right here. I got that chill over Sam. Fast, |
|
| 208:43 | Yeah. Slow. F OK. got it. But what's ignored is |
|
| 208:51 | fact that the normal ones, its coefficient is proportional to density also and |
|
| 208:59 | density is greater, then the sand in here proportionately. So when you |
|
| 209:06 | at the reflection coefficient, you see the reflection coefficient is negative and it |
|
| 209:12 | negative all the way down to 13,000 . So there is no really major |
|
| 209:22 | coefficient associated with this plus that was over Sam. And that shows the |
|
| 209:32 | of density, especially shell versus I'm gonna let you take your own |
|
| 209:40 | to read these differences above versus below of abnormal pressure. And that's oh |
|
| 209:48 | was 319 wells, excuse me, were analyzed in this. No, |
|
| 210:00 | while the equation versus what was actually is showing here here's velocity versus density |
|
| 210:11 | Wiley type of an equation. And , they had the matrix delta T |
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| 210:20 | fluid delta T and this is the what they predicted would read. And |
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| 210:29 | data set was analyzed these thoughts. then this type of an equation right |
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| 210:38 | was fit these triangular points and it wow, the best fit for this |
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| 210:46 | of an equation does not look like wily time average equation that I have |
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| 210:52 | there. So it says bad to in unconsolidated sentiments. If we go |
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| 211:05 | and use things such as the density sand and use a gardener type of |
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| 211:10 | equation, we see that the shell OK. You can gas stronger equation |
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| 211:19 | much predicted what the shell should be an actual value. It's the |
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| 211:25 | And so their new equation. Remember told you that Arco's equations weren't |
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| 211:32 | He put the false values in And this is one example right |
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| 211:39 | User beware out of Stanford comes a bunch of equations and some |
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| 211:49 | a lot of data and Stanford Let me see. I'll tell you |
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| 212:20 | this right here. I want to down a little more salt that I'm |
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| 212:24 | right now. So I'm gonna end day, half an hour early. |
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| 212:31 | . Um and we will pick up . Is that OK with you or |
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| 212:37 | you want your money back? You your money back all of it? |
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| 212:44 | . I'll, I'll, I'll write record position for that. Yeah. |
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| 212:49 | is there any, any questions before dismiss you all over s over the |
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| 212:55 | side? I we can talk about else. I just don't want to |
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| 212:59 | more new material. II, I everybody is, the word isn't |
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| 213:05 | It becomes more than that I think drive y'all smelling good. You must |
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| 213:19 | know what the score is. Javier as he tells the score, what |
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| 213:25 | it? Yeah, it's 10. , does that mean Houston? Seven |
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| 213:30 | 3 1010 3. Houston. Ravens. Oh go away. Who |
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| 213:37 | you? Ok. What's |
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