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  4. Proposed Analysis Workflow

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- [Instructor] So what would I suggest? So I've talked a lot about some of the issues with core analysis and where I see the delta between retort and Dean-Stark and how you can try and get those back on an apples to apples comparison and just the idea that you know while the analytical measurements may be being done correctly, the way it's getting inverted into the reported spreadsheets and the way the results are getting handed over to the operator, are very, very different vendor to vendor and very, very assumption dependent. And how you handle the missing weight there is critical to the final result. So what I have, and this is also detailed in the paper, it's just kind of a workflow that I would, that we see as a little bit of the path forward for core analysis, in trying to get back to you know, if you think back to my rock schematic, how I get back there and start breaking down those critical components, as I step through my core analysis. And then try and get to some level of predictive power. So, we've been focusing a lot more on retort, and that's kind of what I have in this recommended workflow, but also with these post extraction grain volume measurements, a lot of checks along the way, doing measurements in weight and fully accounted for the missing weight through the process. I also recommend as received TOC along with post extraction TOC so that you can ultimately check any vitamin correction you might have, and checking everything by helium porous symmetry is critical too. You'll probably see a difference between the helium porous symmetry numbers and the fluid summation velocities that you can get from retort, and that's just anything thing to think about in terms of the uncertainties around core analysis. And then the plot I'm showing here on the right hand side is a comparison of water recovery 105C. So one of the critical components that I had there in my little rock schematic that I literally stole from Brain Taba by the way, but this little schematic that I have, I saying ultimately we want to get to produce fluid volumes that'll be able to predict what I can flow through the rock from a water and oil perspective, and then in the water perspective I need to break that into mobile and immobile fractions. So that's a typical application of retort where people say, okay, can I separate my clay bound water and my free water, and then you say, okay, what temperature set do I use? And the typically used temperature step here is 105C. This is kind of the common industry standard. Most vendors are retorting to this type temperature step, and what I'm trying to show here is the two vendors have very, very different water recovery at that temperature step. So we already saw earlier that the total water recovery was almost perfectly linear, one to one, both vendors recovered a very similar amount of water when you normalize for rock size, where as here at 105 degrees C, very, very different answer. You see much higher water recoveries from vendor B than you do from vendor A, and so the point I'm trying to make is that you don't have necessarily an apples to apples comparison at the same temperature. So this speaks again to the uncertainties around this and the fact that you've really gotta either choose a vendor and a set of equipment and run with it, or start using TGA or something to calibrate these critical temperature steps for your rock type and try and tie this back to clay bound water. Use your XRD, try and think of ways that this can actually become predictive rather than just saying, okay, 105C is my temperature step that I do regardless of what clay I'm in, what kind of rock I'm analyzing, or what vendor I'm doing it, and then the equipment comes into that too. So how much water hold up do you get? Can you purge the system? Is there a way to effectively flow the water and recover the water on consistent basis?