- [Lecturer] So then we get into the results as they're reported back so this is the spreadsheet you get back from the vendor so you drop off your core analysis and then you wait however long depending on the queue and eventually you get some spread sheet posted and you say okay this is my porosity and then you don't do anything more with it. Right, you just put that into your model and you're done. So, I challenge that a little bit but this is kind of that idea. So this is a spread sheet that you get back and what I have this broken into in the four plots here on the left hand set of plots is technique. And then the right hand set of plots is vendor. So under technique I'm showing Retort vs. Dean-Stark and then the two vendors, a hunk, have a constant. So with Vendor A you see very, very close fit between the Retort, which is on the right so it's in the Dean-Stark on the right. So this is very close to one to one trend line. If I go down to Vendor B there's a significant shift here. So the Dean-Stark is consistently reading higher. So I've already introduced some level of a problem with Vendor B here and Dean-Stark is reading 14% and my Retort's reading 12%. So I've got about a 2 PU shift there by technique. And then if I move to compare vendor to vendor Dean-Stark very, very close again on the top right here on a one to one trend line. And the bottom right hand plot illustrates that same point I just made which is that Vendor A has a systematically higher Retort porosity than Vendor B. I mentioned the bitumen correction too, the assumption here is that there's very little bitumen in these samples so the benchmark tends to be bitumen lean and we have quite a bit of evidence for that I can't really get into it here it's not really part of the topic but I just want to throw that out because that's something that people would say is the typical shift between the Retort and Dean-Stark Analysis. So that's porosity space, now I want to touch on saturation space and water saturation and oil saturation and show the differences here. So water saturation is close to one to one, there's definitely some scatter here around. So the bottom left plot there's definitely some scatter around, a little bit of noise between the two vendors but generally close to a one to one. If anything, you'd say the Retort saturations are trending slightly higher than the Dean-Stark saturation and both vendors seem to be spanning a similar water saturation vein again similar numbers with just a little bit of noise as I mentioned. On the oil saturation side you see a completely different story. So between Dean-Stark and Retort here we're not even close to a one to one trend line. So in Dean-Stark I'm spanning up to 20% oil saturation and then my highest Retort saturation is hovering at around 10% oil saturation. So I'm getting almost double on average the oil out of the Dean-Stark than I am out of the Retort and the other thing that gets introduced here is a significant shift between the vendors. So Vendor A is reporting significantly more oil saturation on the Retort than Vendor B. Still not as high as Dean-Stark but significantly more than Vendor B. And several of the samples here with Vendor B reporting 0 Dean-Stark oil saturation Sorry Retort oil saturation. So can we reconcile the differences? The answer up front is you generally can. So we asked each vendor to provide the raw data so that's weights, volumes, everything tracked along the way to allow us to go back in and recalculate everything to get everything try and get everything at least back on to an apples to apples comparison using the same set of assumptions the same fluid densities, same oil density, water densities, correcting brine volume to distilled water volume. Using all the same corrections there are and see if you can get it back to looking the same. So what I have here on the top right hand quad is a comparison of Water Recovery. So you see Vendor A Water Recovery and Vendor B Water Recovery and this is total Water Recovery through the Retort process. And now just to highlight this I'm focusing now on Retort because my Dean-Stark is very, very closely in agreement. So what we saw was a significant difference in the Retort analysis and that's what I'm gonna hone in on over the next few slides. So the Water Recovery, you see this is very, very close. So this is normalized grams per 50 grams. So grams of water recovered per gram of rock that I had and you see very, very close in agreement. So this is almost exactly a one to one trend. At which point you say okay so my water saturation's are close but not ideal and this is a little surprising to me. But if I go into the Retort porosity space, recalculate it using the same assumptions now I'm at a one to one trend line. And if you recall back a couple slides ago I saw a significant shift between the two vendors and so you say okay so why are these suddenly so different why were they so different originally? And it comes to the quirks of the topic here, how do you account the fluid recovery? So how you're basically inverting your weights and volumes, back into porosity space using assumptions and how you end up calculating your total porosity. And there's a fundamental difference between Dean-Stark and Retort here in terms of that computed Oil Recovery. So we saw the Water Recovery was very, very close and if I look at Oil Recovery it's similarly normalized in grams per 50 grams. Each sample here is showing huge delta between both vendor and the amount of oil recovered by technique. So if I take sample number one as an example and recovering not even a CC but like .02g of oil using the Retort and then on Dean-Stark I'm inferring up to .2g which is a significant shift. And then several of the samples as I mentioned on the oil saturation plot actually recovering zero oil in the Retort and yet have this significant oil recovery in the Dean-Stark. And so you get to the question okay what is the difference here? The difference is by how you calculate this. So its important to remember that in Retort what you're assuming is that you're recovering all of your oil so you're Retorting this off and I'm getting a physical volume of oil recovered. In Dean-Stark I'm never doing that so in Dean-Stark I'm weighing I'm recovering my water and I'm getting my original starting weight recovering my water in the sample the volume and correction and then inferring the missing weight between the total and the final is my oil weight because I've subtracted out my water weight already. So I'm inferring the water weight and so what you're seeing is this inferred oil measurement is significantly higher and what you see in the Retort is the direct oil measurement. So that's a little complicated but the assumption that as well is that all the missing weight that you have in Dean-Stark is oil and then you get into the Retort where you summon things by volume and not summon things by weight. So if you start summoning things by weight what do you see? So these are fundamentally different measurements. So again the plots here I'm showing Retort vs Dean-Stark and these are the plots as before but these are recalculated. So I'm going to reach my porosity with Dean-Stark. My Dean-Stark is consistently higher from both vendors and they both look very, very similar. As you saw before my recalculated Retort porosity was also very great so what's that suggesting is that both vendors are analytically performing this experiment very, very similarly but ultimately coming to a very, very different result. So this missing weight, if you don't think about it can cause a significant porosity shift. So in the Retort example you know I mentioned that Dean-Stark you're doing total minus final weight the Retort calculations can be done in multiple ways. You can either do these by weights or volumes. So the Retort assumption is again I'm recovering all my oil volume I'm recovering all my water volume and I have a starting grain volume and so I can summon my total porosity by volume. I can also weigh those three reflections. And do it that way by assuming fluid densities for the weights and inverting. So the question becomes how does the final Retort weight look compared to the volumes that I'm inferring that I've recovered. So if I recover 10g of water and then 1g of oil as a hypothetical example I should assume that then my retort volume and weight has changed by 11g. And what we're saying is that's not the case we're actually seeing a significantly greater loss in the Retort total weight more akin to the Dean-Stark weight but we're not fully recovering those volumes and so that's what I'm referring to here when I say the missing weight so this is weight loss in the same boat that is not accounted for in the fluid volumes you've recovered. So now I'm going to pivot a little bit and talk about Routine Core Analysis as I mentioned we did a single core here Reaching core analysis is typically something that's disregarded entirely on conventional rocks where you don't have a lot of porosity permeability, ability to effectively clean the rocks for example, or its very time consuming to do so. So one showing on the plot here is a crushed Dean-Stark porosity on the X axis so the data I've been referring to earlier on this is the plug Dean-Stark porosity that we were able to get. And what you see is a very, very close agreement here. So I'd say this is extremely one to one with the exception of maybe at the low end on this 4% porosity plug that's when you start seeing a little bit more separation from the one to one trend line but very, very close agreement. So just a little bit of support here that you can actually apply Routine Core Analysis into unconventional samples for significant cost savings and still get very repeatable and reliable results and this also mitigates the idea if you have fluid loss during crushing or any problems like that and if you had a single rotary plug that you've taken on the Y line for example. You don't have to destroy the sample so its non-destructive you could do this and then reuse the sample for another kind of four point testing, right?