| 00:01 | this conference will now this conference will be recorded. Okay, there we |
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| 00:06 | . So you can all see the then and you can hear me |
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| 00:12 | Okay, so picking up where we off, we were talking about fluid |
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| 00:19 | and this is an interesting one from historical perspective. These were measured compression |
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| 00:28 | shear wave velocities in a shell on of production. And you can see |
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| 00:38 | compared to the mud rock line. we did a fluid substitution on the |
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| 00:44 | rock line and got a gas share . And also we have the gas |
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| 00:49 | , which you remember V. B. S. Of 1.5. |
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| 00:54 | and where these points plot is very . They plot between the mud rock |
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| 01:01 | and the predicted gas shale line. at the time this was done in |
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| 01:07 | late eighties, at the time we this as being due to gas in |
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| 01:13 | shell. But gas men's equations due the impermeable itty of the shell, |
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| 01:22 | totally accounting, were not properly quantitatively for the effect. Nowadays. Uh |
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| 01:30 | understand better that this is probably because was an organic shell and the effects |
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| 01:37 | just the solid organic material is to the B. P. B. |
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| 01:42 | ratio. So um early on we the idea that they were hydrocarbons in |
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| 01:50 | . It never occurred to us to them. I was thinking in terms |
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| 01:55 | how the seismic response would be then we would think if we were |
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| 02:00 | the mud rock trend. So this a definite uh example of how you |
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| 02:07 | violate the mud rock trend, adding will lower the B. P. |
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| 02:12 | . S. But so will be solid organic matter. This was some |
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| 02:28 | data collected in the late 80s. this was an interesting situation where we |
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| 02:34 | looking above known fields. And we looking in the relatively shallow near surface |
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| 02:43 | at the time we didn't have di logs. What we were using were |
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| 02:50 | surface to hold the SPS with very spaces. And we were measuring p |
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| 02:57 | velocity and shear wave velocity that And here we have a shell trend |
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| 03:03 | we have a brian trends and off reservoir on on the flanks we got |
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| 03:13 | kinds of V. P. S. Ratios we were expecting for |
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| 03:17 | saturated plastic silicate rocks. And you these velocities are pretty low. All |
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| 03:25 | . But then we made measurements over field and to our surprise, what |
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| 03:34 | see is primarily an increase in shear velocity. Not so much a decrease |
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| 03:39 | p wave velocity. More of an in share wave velocity. And this |
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| 03:46 | with geochemical data that was suggesting that the near surface over this field there |
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| 03:53 | microbial activity that was chewing on the that were seeping above the reservoir and |
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| 04:03 | cements. So this was consistent with geochemical idea of uh finding these cements |
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| 04:12 | the near surface being indicative of hydrocarbons . So what cement would do would |
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| 04:18 | to increase the the uh excuse cement would increase the shear wave |
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| 04:25 | It would also increase the p wave . But you have the counteracting effect |
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| 04:30 | the hydrocarbons on the p wave So primarily we're seeing uh the shear |
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| 04:38 | velocity being increased uh by the cement . So a bigger increase in rigidity |
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| 04:47 | in fact a slight decrease in P velocity. Okay. Some things to |
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| 04:58 | about when doing fluid substitution. First all, as I've tried to |
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| 05:04 | think about the actual experiment in the . What are the logs reading? |
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| 05:11 | density log only reads a few inches the formation. So it's reading the |
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| 05:16 | zone. And hydrocarbons may be flushed from the borehole by drilling mud |
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| 05:24 | which means you may be reading too density in the in the invaded |
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| 05:30 | So it's the density may not be . Now uh sonic logs can read |
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| 05:38 | fortitude into the formation. However, you have the sonic logs are a |
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| 05:46 | experiment, uh they are refracted head . And I don't know if you |
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| 05:53 | the hidden layer problem. Uh In prospecting. If you have a high |
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| 06:00 | layer, your head waves won't see low velocity layer beneath it. They |
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| 06:06 | refract along that high velocity layer. so if the invaded zone is uh |
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| 06:13 | pushing hydrocarbons away from the well It's possible that the invaded zone is |
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| 06:19 | velocity. Um Of course you would to flush all the hydrocarbons for that |
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| 06:24 | happen. Uh But the net effect it's possible the sonic logs may or |
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| 06:31 | not see the hydrocarbons. And quantitatively the velocities may not be strictly |
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| 06:40 | Uh And if you have a very balanced mud so that you have extreme |
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| 06:46 | invasion, you may see little hydrocarbon on the laws. Uh Also, |
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| 06:54 | we we discussed last time about bubbles from the formation, gas getting out |
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| 07:01 | formation into the drilling fluid and attenuating sonic signal causing cycle skipping when you |
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| 07:09 | gas sands. So there are a of reasons to be suspicious of what |
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| 07:15 | the measurements in the vicinity of your . Uh And for this reason we |
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| 07:24 | the sonic and density measurements more in brine saturated formation. That in a |
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| 07:31 | saturated saturated formation. And for that , if I have a choice to |
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| 07:39 | from to take the velocities in the sand and predict the velocities in the |
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| 07:45 | sand or to go the other way the velocities in the brine sand. |
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| 07:51 | mean, measure used the measured velocities the brian sand to predict the effect |
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| 07:56 | velocity and the hydrocarbon sand. The is the better way to do |
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| 08:01 | And in fact checking that compatibility between results. Um seeing if you get |
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| 08:09 | going in both directions from gas to and from bryan to gas um that |
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| 08:15 | increase your confidence that you're you're measuring velocities. Okay. We also talked |
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| 08:21 | the density log being sensitive to whole . So washed out zones are usually |
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| 08:29 | low density um kind of a fine . Don't put too much hydrocarbon in |
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| 08:38 | sand. Uh Sometimes we see people a brine sand and replacing all the |
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| 08:45 | with hydrocarbons. Well, that never in nature, right? You always |
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| 08:49 | some residual water saturation and the er the rock the higher that residual |
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| 08:56 | saturation usually is. So uh you , try to be realistic in what |
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| 09:01 | hydrocarbon saturation is going to be and common error that I've seen time and |
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| 09:10 | , uh huh If you're reading velocities the drilling fluid velocity like 190-195 microseconds |
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| 09:20 | foot or slower. There's no way velocities are accurate. It would have |
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| 09:27 | be an extreme coincidence for those velocities be accurate because uh if the formation |
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| 09:35 | slower than the drilling fluid, it's a precise moment. It's a |
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| 09:39 | experiment as sonic refraction experiment. If drilling fluid is faster than the |
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| 09:46 | the sonic ill will measure the drilling velocity. So gas vans, shallow |
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| 09:52 | sands could have velocities much lower than fluid velocity, but the sun oclock |
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| 10:00 | see it. So be aware of situation. Okay, so uh let's |
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| 10:09 | an exercise. Let's do this with equation. And so here we calculated |
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| 10:16 | fluid properties and there's a live oil is here and a dead oil module |
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| 10:26 | . Remember to use giga pascal's and uh, Woods equation to calculate |
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| 10:35 | the fluid module is the effective fluid versus water saturation for the live oil |
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| 10:42 | for the dead oil. And let's those two. Do you follow |
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| 10:47 | We're going to vary the water saturation 0 to 1 and we're going to |
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| 10:52 | Woods equation to calculate the effective module using 1.2835 giga pascal's for the live |
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| 11:02 | and then 1.635 giga pascal's for the oil And compare those two curves. |
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| 11:11 | while you do that, I'm going stop recording this conference will now be |
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| 11:18 | . Oh, early on, when were talking about velocities, I told |
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| 11:24 | about an empirical trends that I developed brian sand and gas and velocity. |
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| 11:31 | gets you in the ballpark. I , there are lots of variables, |
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| 11:34 | fluid properties, etcetera, all kinds inputs. Uh it can't, there |
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| 11:42 | to be a lot of scatter around for one thing saturation, right? |
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| 11:47 | as the first guess this is remarkably . Uh, if I know the |
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| 11:54 | sand velocity, I don't, instead going through Gassman, I just use |
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| 11:59 | equation. So, again, it's one of these polynomial, um now |
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| 12:08 | another approximation which was from Moscow and took gas mains equation, You may |
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| 12:17 | this form, This was the Brown Karenga form and he just replaced the |
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| 12:21 | modules with the plane wave modules. is no theoretical justification for doing |
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| 12:29 | This is what Mapco calls a heuristic . And he said that the, |
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| 12:36 | error due to this is uh, more than three Or is on the |
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| 12:42 | of 3%. So why not do instead of that? And I wrote |
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| 12:51 | paper in response saying that that's not right criterion to judge how good the |
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| 13:00 | substitution approximation is. It's not the in the predicted velocity, it's the |
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| 13:07 | in the change of velocity due to change in fluid modules. That's what |
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| 13:13 | . And I showed that this error be on the order of 100%. |
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| 13:18 | paper was rejected. It was Obviously someone from the stanford mafia was |
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| 13:23 | of the reviewers and their notes were , this constitutes a diabolically clever to |
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| 13:32 | to mislead the public, But anyway, so now, 20 years |
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| 13:39 | it's still a sore point with It's kind of funny. Um, |
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| 13:45 | you know, if we had time would compare these approximations, but I'm |
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| 13:50 | to jump ahead and I'm going to yeah. Oof we had already |
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| 14:03 | I believe we already talked about that , but what I'm going to do |
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| 14:07 | , I'm going to do what is stochastic simulation. I think there, |
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| 14:12 | is an important era here, or an important thing to consider |
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| 14:18 | Um and we're going to compare using the Mapco or the Castano approximation. |
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| 14:24 | going to compare to the exact Gassman and the uncertainty in the gasman result |
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| 14:32 | to errors in the input parameters. what what what I'm going to show |
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| 14:37 | is that all these input parameters, module list, ferocity, saturation |
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| 14:44 | um dry frame, you know, modules, all these inputs, we |
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| 14:52 | know those inputs perfectly well. And a result, we're introducing error into |
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| 14:58 | gasman prediction. So we could be , very precise, but it doesn't |
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| 15:03 | because we have an exact theoretical but it doesn't mean that that prediction |
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| 15:09 | accurate. It just means we're we're the number, we put the same |
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| 15:15 | , we get the same output So it's a precise calculation, but |
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| 15:19 | can be precisely wrong if my input are wrong. And so what I'm |
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| 15:26 | do is I'm gonna run stochastic I'm gonna uh create a probability density |
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| 15:35 | for each input parameter. And I'm to randomly draw from this probability density |
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| 15:42 | and then I'm going to calculate the results. So for example, I'm |
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| 15:52 | to put error bars on my In fact, even with with sonic |
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| 15:58 | , we don't know the p wave perfectly. I've shown that you can |
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| 16:05 | on the order of a 2% error uh in the p wave velocity and |
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| 16:10 | the order of a 5% area with shear wave velocity. So, I'm |
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| 16:15 | in a slight error in those. going to put a slight error |
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| 16:19 | in the density in the porosity We don't know the solid grain module |
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| 16:27 | perfectly. And just for the sake argument, I'm going to assume we |
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| 16:31 | the brian modules. We don't because don't know the salinity. We have |
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| 16:36 | know the salinity and calculated at the institute pressure and temperature. I'm also |
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| 16:42 | to ignore all of these things which have uncertainty, for example, the |
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| 16:50 | density, if I don't know the , I don't know that perfectly. |
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| 16:54 | don't know my water density. If don't know the salinity, I don't |
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| 16:59 | my gas module is perfectly, or gas density, I'm going to |
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| 17:05 | Also, I know my initial water perfectly and the water saturation of uh |
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| 17:12 | the thing. I'm trying to compute . Remember, I haven't drilled the |
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| 17:17 | yet. I haven't drilled drilled my yet. I don't know what saturation |
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| 17:22 | actually represents. So, but I'm all of these possible uncertainties and only |
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| 17:29 | uncertainties in these guys. And I at, I have a the Known |
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| 17:43 | , I start here, the known is four km/s. So that's my |
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| 17:50 | D. P. And now I'm add gas. The O. Is |
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| 17:56 | original VP. I am, let's , oh, he is the exact |
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| 18:04 | prediction. M is the median value the distribution. Um, no, |
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| 18:13 | sorry. M is the math go of the distribution. Okay, and |
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| 18:18 | medium value, I think winds up pretty close to the exact value in |
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| 18:23 | class case and notice the Castano approximation virtually the same as the exact |
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| 18:30 | Whereas math goes approximation is off Okay, let's look at another case |
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| 18:38 | now I'm going to open it up little bit more. Okay, it's |
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| 18:40 | same thing, but I'm opening up like uncertainty in the gas properties and |
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| 18:48 | at that enormous range. So I at four kilometers per second actually, |
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| 18:55 | combination of parameters could give me a increase. Uh Castano approximation exact |
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| 19:03 | Mafco approximation. The media is pretty , the median of the distribution is |
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| 19:09 | close to the exact, but look that tail on the distribution, |
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| 19:15 | So, enormous uncertainty and the uncertainty so much bigger between than the differences |
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| 19:23 | the approximations from the exact value. , we're going to try a higher |
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| 19:32 | , so this is a lower So the error and ferocity is much |
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| 19:37 | as a percent error. And that has an enormous error here in |
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| 19:46 | case. Mapco is right on the value and mine is a little bit |
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| 19:53 | , but again, compared to the of possible answers. The difference between |
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| 19:59 | exact and the approximation is small compared that entire range. Okay, so |
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| 20:08 | do one more. This is a velocity rock. And here we see |
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| 20:13 | an enormous difference. Um Castagna is close to the exact answer, but |
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| 20:22 | is his way off here. by the way, this is assuming |
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| 20:30 | mains equations are perfect. There are uh you know, Gassman isn't |
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| 20:38 | It's correct in a theoretical world, there are complications like if there are |
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| 20:45 | mineral components. Um gas use equations slightly an error. If there is |
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| 20:54 | low permeability gas mains equations or an doesn't take into account dispersion and also |
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| 21:02 | effects of invasion. So there are of other things going on, not |
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| 21:06 | mention catastrophic errors in the density or sonic. I only was dealing with |
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| 21:13 | errors. So what I concluded and presented these results at the scG uh |
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| 21:22 | that the uncertainty and the flu substitution is a lot larger than the predicted |
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| 21:28 | in velocity. Uh and it's usually the error is usually larger than errors |
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| 21:36 | the approximation. And for that I'm not reluctant to use the approximations |
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| 21:43 | I understand they were only giving me ballpark answer. And then in |
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| 21:48 | uh if I'm trying to understand seismic responses, I knew to |
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| 21:53 | I need to model the hydrocarbon effects . Okay, so I think another |
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| 22:04 | lesson uh uh fluid substitution. These thai lines between laboratory measurements on saturated |
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| 22:16 | dry rocks and we have a saturated which might be the mud rock trend |
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| 22:23 | something close to it? And we our dry line which was P. |
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| 22:28 | . B. S. 1.5. the open circles are the dry |
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| 22:39 | Most of them follow the dry There's one up here which was highly |
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| 22:44 | Calgary is cemented which is off and was cemented. So the fluid effect |
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| 22:50 | pretty small. Uh And these are lines for the same sample measurement on |
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| 22:58 | saturated rock measurement, on the uh the dry rock. And a few |
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| 23:05 | you'll notice here, we were these beach sands. And you got an |
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| 23:14 | which is kind of similar to what expecting in theory where there is not |
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| 23:18 | big change in shear wave velocity from to dry, a slight increase due |
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| 23:24 | the density effect. And Uh A big drop in the P wave |
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| 23:33 | . Now, these other measurements though kind of interesting. We're going from |
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| 23:39 | to dry and we're seeing two different of behavior. We're seeing shear wave |
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| 23:45 | dropped tremendously along with the big Wave velocity trial, we're also seeing |
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| 23:52 | points where she will shear wave velocity . All right, so, um |
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| 24:00 | these are on the same rock So, even though the tendency is |
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| 24:05 | , the trend is more or less , it moves you from the |
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| 24:08 | saturated trend to the gas saturated Something else is changing In some |
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| 24:15 | the shear wave velocity is increasing, a lot, some kind of times |
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| 24:21 | decreasing a lot. Um Can you what's happening with some of these |
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| 24:30 | Why would the shear wave velocity Um Or actually I'm saying if I |
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| 24:36 | from dry to wet, the shear velocity is increasing right, uh here |
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| 24:44 | going dry to wet and the shear velocity decreases. So could you explain |
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| 24:51 | two different kinds of behavior happening when theory is telling us there shouldn't be |
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| 24:57 | big change in the shear wave Well, when I remember when, |
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| 25:12 | we talked about the poor pressure, had it had two implications on on |
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| 25:17 | VP but one of them was bigger the other. That the bigger one |
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| 25:21 | that it's often is often the the rock matrix but uh but it's also |
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| 25:28 | and that softening of the of the the of the matrix models um uh |
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| 25:36 | the velocity to slow down. Um , but you're this to pressure and |
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| 25:42 | forgot to mention that these measurements are at the same differential pressure. |
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| 25:51 | these timelines are connecting points with the differential pressure. Okay. Yeah, |
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| 26:00 | was going to say eventually there are different pressure. Okay, yeah, |
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| 26:04 | , that would be a good good . Um I just forgot to mention |
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| 26:09 | at the same pressure. Yeah. . Let me ask you a different |
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| 26:23 | . Why would the shear wave velocity when I add water. Their city |
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| 26:32 | increasing uh well, density increasing with what's going on here. Yeah. |
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| 26:50 | effect, yeah. Okay good. a good hypothesis. Uh accept this |
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| 26:56 | is too big to be explained. seeing these very porous rocks. The |
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| 27:01 | effect is relatively small here. We're a much higher velocity rocks. So |
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| 27:06 | ferocity is probably a lot less and the effect is much much bigger than |
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| 27:12 | density effect. So yes, that's a good hypothesis but I think it's |
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| 27:18 | enough to explain this difference. Could it be that just the fluids |
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| 27:26 | impacting the the the the rigidity of rock? That's exactly right. If |
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| 27:34 | have clay's in Iraq you add You could reduce the richard ideology. |
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| 27:41 | this is an example of frames All right, well, no |
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| 27:48 | Well, if we reduce the dignity actually reducing the V. S. |
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| 27:55 | , that's what's happening. You see have high V. S. And |
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| 28:00 | add water and I lower the S. I ain't going away from |
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| 28:06 | yeah, I'm sorry. I originate black to the blank. I was |
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| 28:12 | black is with water saturation. Open is dry. Okay. Okay. |
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| 28:19 | we going backwards. Okay. So would invoke frame softening for this guy |
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| 28:26 | , how about these guys? An increase in shear wave velocity when I |
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| 28:34 | water. It's an unfair question. think the answer. I think the |
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| 28:51 | here is I said these were at same pressure, but I didn't say |
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| 28:56 | had the same pressure history, he's . I'm gonna say this is this |
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| 29:03 | be due to history says, the pressures, they probably made the |
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| 29:10 | on the dry rock, increase the all the way, then added water |
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| 29:18 | made the measurements again on the same which had previously been subjected to higher |
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| 29:27 | . Okay, so I think we're a history since effect here. |
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| 29:42 | so, um yeah, let's do questions. Since you have your test |
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| 29:50 | Wednesday. So true of false gas equations are the high frequency limit of |
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| 29:57 | theory. Fools. Yes, there the low frequency limit. Okay. |
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| 30:07 | p wave velocity for porous sandstone is ft per second, a likely gas |
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| 30:14 | velocity predicted by gas mains equations is 81 100 ft per second. The |
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| 30:21 | C 90 400 or be 1550 And a key word here is |
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| 30:39 | Does it have to be just my can be too uh well, let's |
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| 30:44 | the most likely the Yes, that's . I mean odds are it's not |
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| 30:51 | to increase and it's a sandstone. odds are it's not going to increase |
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| 30:57 | At 8000 ft/s. That's probably too in effect To go to 1550. |
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| 31:06 | the most likely answer is 60 Okay, the velocity of water is |
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| 31:13 | we're as close to which of The answer is all of the |
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| 31:20 | Actually 5000 ft perspective translates to 200 per foot. But as far as |
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| 31:26 | goes, these are all pretty So if you see things flatlining at |
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| 31:32 | water velocity Uh huh. Don't believe velocities. Okay, if shear wave |
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| 31:39 | for porous sandstone is 2800 ft per , a likely gas and velocity predicted |
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| 31:46 | gas months equations is which of Gas in p wave velocity? Ha |
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| 32:10 | . Well, this is the shear velocity. The result has got to |
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| 32:15 | a V P B s ratio more square were too too Right. So |
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| 32:20 | can't be any of these. It's . So this is the only one |
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| 32:26 | would give us a person's ratio greater zero. When gas men's equations are |
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| 32:41 | to invert ultrasonic velocity measurements for frame it the predicted ratio of frame both |
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| 32:48 | over sheer module is on the average than one. About one less than |
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| 32:55 | . So these are not the ratio dry rocks there, the ratio and |
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| 33:02 | rocks using gas men's equations about Well, they should be about |
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| 33:11 | If it was dry rocks it would about one. And if we use |
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| 33:14 | correct Vo equations, as we discussed time, the answer would be about |
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| 33:20 | . But if we apply gas mains which are the zero frequency limit. |
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| 33:26 | we apply them to the laboratory measurements extract uh The ratio of frame marge |
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| 33:34 | , which is greater than one. , now for the next one, |
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| 33:41 | answer is about one when persons ratio .1. The ratio of bulk over |
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| 33:47 | module I is. The answer is one true or false. Rock saturated |
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| 33:55 | live oil generally have higher velocities than same rock saturated with dead oil. |
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| 34:07 | false. It's the other way True of false rock saturated with heavier |
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| 34:13 | oils open have velocity similar to gas of the same ferocity. The gas |
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| 34:33 | is a lot bigger than heavier dead . So the answer is false. |
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| 34:41 | false. Live oils and gas can similar fluid substitution effects and the answer |
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| 34:49 | yes. Can doesn't mean they always but they can if you get too |
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| 34:53 | temperatures high geo are live oils can properties very similar to gas. |
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| 35:00 | true or false. Gas ends generally higher V. P. V. |
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| 35:04 | . Ratios than grinds, sands proof false. True or false oil sands |
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| 35:14 | have higher V. PBS than the shells. It's possible. I think |
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| 35:25 | possible. Yes. Okay, true false. If x gas exalted from |
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| 35:32 | or water rock velocities can decrease significantly to that's true. So if I |
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| 35:43 | the pressure and uh gas could come of solution. If I come below |
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| 35:49 | bubble point and the velocities can decrease . Okay, I want to jump |
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| 35:57 | an important summary graph. I want get this in before we're done. |
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| 36:04 | that's this one. So I'm uh complete the table together and I don't |
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| 36:13 | the answers in your note. I believe so, you may want to |
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| 36:17 | down the answers as we uh note . So uh complete the table. |
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| 36:25 | for example, I'm increasing ferocity. happens to VP? It goes |
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| 36:30 | what happens to be s it goes , what happens to density? It |
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| 36:34 | down If I'm in a plastic VPs go up and if I'm in a |
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| 36:41 | , um it could stay the So you see, you see the |
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| 36:48 | this works, we're changing one thing we're holding everything else constant. |
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| 36:56 | So if I increase the confining pressure hold everything else constant, that means |
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| 37:02 | differential pressure is going to be Right? So confining pressure up, |
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| 37:09 | goes up. V. S goes . I mean, excuse me ves |
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| 37:13 | up, density is not going to a lot. So it's going to |
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| 37:18 | more or less the same in the rock. The PBS will go down |
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| 37:23 | in carbonate. Be PBS will say the same you with me on |
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| 37:30 | So you ready for the next Okay, so I'm gonna pour pressure |
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| 37:35 | going up. That means I'm holding pressure a constant. So as I |
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| 37:42 | the poor pressure and I'm holding confining constant. My differential pressure is |
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| 37:50 | Right? So holding everything else As I increase the poor pressure. |
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| 37:56 | happens to VP down? Well what to be s down soup? |
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| 38:07 | What happens to density? Same? , more or less it will uh |
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| 38:14 | will density will go down because the increases. But it's more or less |
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| 38:20 | same because it's not a big What about B. P. |
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| 38:23 | S? We're in a plastic We'll go down. No velocity is |
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| 38:33 | down. Think of the mud rock as VP goes down. What happens |
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| 38:37 | be PBS? It goes uh right as we as we consolidate box as |
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| 38:45 | increase the effective stress on them, V. P. B. |
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| 38:48 | Goes down if we increase the poor were decreasing the effects of stress. |
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| 38:55 | be PBS goes up. Okay. . Okay, effective pressure up. |
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| 39:04 | means I'm changing combining pressure and pore together. Right? So effective pressure |
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| 39:10 | up. VP goes soon. Uh . It's the same as Yes, |
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| 39:19 | VP goes up. V. Goes up. Density doesn't change very |
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| 39:25 | what happens to V. P. . S in a plastic. The |
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| 39:33 | reduces according to modern times. And in the carbonate we're gonna stays |
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| 39:39 | same. We're going to say pickets are at work. So V. |
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| 39:43 | . B. S. Is 1.9 a limestone 1.8 and dolomite. And |
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| 39:48 | doesn't change. We're ignoring, you , super unconsolidated. Carbonates. |
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| 39:56 | So now play replaces courts. So take courts grain out and I replace |
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| 40:04 | with a clay grain. Okay, happens to BP slower? Yes. |
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| 40:14 | you remember from the frio formation equations Sias equations? Right? Uh As |
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| 40:22 | content goes up, VP goes Okay. What about B. |
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| 40:27 | What happens to the S whose Yes. What happens to density? |
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| 40:39 | or less the same? What happens be Pds goes up approaches infinity. |
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| 40:53 | . And for uh carbonate? Uh a big difference. Right? We're |
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| 40:58 | gonna have a lot of courts in in a carbon A All right, |
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| 41:03 | uh calcite replacements quartz? What happens VP? I grew up? |
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| 41:10 | What happens to be S. You can say what is the same |
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| 41:22 | now, CBS is the same. PBS goes up, right? And |
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| 41:29 | BP is going up, let Bs the same. Okay, density |
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| 41:36 | Yes, be pds of increase. in a carbonate. Yeah, courts |
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| 41:46 | ports to carbonate lowers free PBS. taking the courts out adding calcite increases |
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| 41:52 | B. P. B. Okay. Dolomite replaces calcite VP |
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| 41:59 | Yes, that's if I replace a crystal would indulge my crystal. Keep |
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| 42:05 | mind when I dial the ties. . Um I could increase the |
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| 42:10 | So there are counteracting effects. But everything else is constant. The |
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| 42:17 | is constant. Dole might replaces calcite goes up. What about Bs |
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| 42:29 | Okay. What about density again? it's interchangeable with the ferocity here but |
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| 42:39 | it can go up. Yeah if just replacing mineral by mineral then uh |
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| 42:45 | goes up. What about the Uh huh. Down Dolomite has the |
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| 42:56 | be PVS and castle Nunes. Uh . Okay. And same thing in |
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| 43:03 | carbon because it is well it is carbon. Right? Okay. Blair |
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| 43:09 | porosity. Same model. They replace the same biomom ferocity. Usually |
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| 43:22 | goes up the US goes up, goes up be PVS goes down and |
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| 43:38 | a carbonate. If you follow the rock high velocity it's um lower |
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| 43:50 | PBS than the limestone. So a limestone should have a lower V. |
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| 43:57 | than a clean limestone. Okay, one should be easy calcite replaces |
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| 44:04 | BP. After the US up density the PBS in a classic that's it |
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| 44:19 | go either way. I don't know same thing in a carbon A I |
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| 44:23 | know. Okay, now limestone is sized. That's not the same thing |
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| 44:30 | element replaces calcite. Right now there be a ferocity change. So |
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| 44:35 | P. I don't know if we up, it could go down. |
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| 44:39 | with the s same with density. be PBS will go down in the |
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| 44:50 | . Okay lift. Ification increases. . Oh the s up up |
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| 45:02 | Uh uh V. P. S. Down. Right? Carbonate |
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| 45:11 | be the same. Okay. Uh increases VP V. S. |
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| 45:23 | Mhm. Oh actually, oh P. B. S. And |
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| 45:29 | plastic. Yes. Yeah. And going to skip a car if I |
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| 45:38 | it, that means there's not a . It could follow up. |
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| 45:44 | Age increases VP of the US. huh. The previous. No. |
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| 45:58 | , depth increases VP the s. density of the PBS. Them. |
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| 46:11 | . Okay. Some gas is Bp don't the US uh and be |
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| 46:24 | slightly up. Yeah, very So you could say the same. |
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| 46:28 | talking to some gas. Not Okay, density go slightly down or |
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| 46:35 | same. Okay, be PVS. . Okay. B. P. |
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| 46:45 | . S. V. P. down. V. S. Is |
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| 46:47 | same. Or up PBS. More gas is added. Bp |
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| 46:57 | Yes. Yes. Up density. , Down the PBS sink. |
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| 47:11 | exactly the same. Uh huh. . Oil replaces brian. And here |
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| 47:18 | talking uh we're not we're not talking heavy oil here. So oil replaces |
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| 47:24 | , B. P. Done down little bit too a lot. |
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| 47:29 | S. C. Pretty much You know, slightly V. |
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| 47:37 | B. S. Flight good. , fractures added to a blind saturated |
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| 47:46 | . Bp. And physiotherapy depending on direction. Yeah. Yeah. |
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| 47:53 | I think you know what? I you guys have got it. So |
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| 47:57 | let's call it quits at this I'm sorry. So sorry, just |
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| 48:04 | . So fractious added in brine, rock. Bp goes up B. |
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| 48:14 | . Uh Oh I'm sorry fractures added goes down. Bs goes down |
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| 48:22 | Be PBS goes up, density doesn't very much. Okay, fractures added |
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| 48:30 | the gas saturated rock. VP goes . Bs goes down, density goes |
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| 48:38 | well or unchanged, and D Pds the same. Okay, frequency |
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| 48:47 | BP goes up, Bs goes Density is unaffected. V. |
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| 48:53 | B. S. Do we know ? I would say if he if |
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| 49:01 | goes up the pds, the PBS goes down, but I don't have |
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| 49:08 | of that. Okay, so it be the same. I would have |
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| 49:13 | the same wrong. Let's put it way. Okay, temperature increases VP |
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| 49:19 | down. V. S. We really know. We saw some experiments |
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| 49:27 | it looked like it was going but it's a B. S. |
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| 49:30 | pretty much the same density. What density do as temperature increases? Go |
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| 49:38 | ? Go down because the fluid becomes dense. So, if VP goes |
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| 49:45 | , what do you think happens to PBS in a plastic goes up? |
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| 49:54 | . Well, the question here. , so, so we're assuming that |
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| 49:59 | Gs is the same and the only is going down? Oh, that's |
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| 50:03 | good point. Oh, that's a good point there. Okay, |
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| 50:11 | you're right, the PBS should go . I need to think about this |
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| 50:18 | , you know, I almost got of here in time and by the |
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| 50:21 | , temperature is cut off from your your slides, so it's not |
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| 50:28 | You're right. I screw it. is the last thing I would do |
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| 50:34 | tape. I'm screwing up. All . Any more questions before we get |
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| 50:41 | of here, feel free to email , Okay, I'm gonna stop recording |
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| 50:47 | I will |
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