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  2. Complexity of the BPS

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- [Narrator] So we talked about the complexities of the Bakken Petroleum System. I'm sure a lot of you petrophysicists out there are looking at the logs over here and the green curve is the resistivity curve and the blue curve is the neutron curve. And you know, really, it's kinda benign, there's not a lot of wiggles going on except maybe here in the shales and the upper and lower shale. And we see it mostly on the gamma ray, but look at this log and see just how complex can it be and it's really a highly complex unconventional system. Primarily because we have these ultra low permeability conventional reservoirs and they're actually far from conventional, they're very unconventional because of the low permeability and low porosity and the small pore throats that we have. And then we have organic-rich black shales with high total organic carbon content, TOC. And we have multiple lithofacies within a lot of these sands. The other thing that makes it very complex is the complex mineralogy. And so this mineralogy is a key component to this unconventional system. The rock textures range from highly bioturbated to finely laminated. And each of these different reservoirs exhibit complex heterogeneous distributions of reservoir properties. Now the best way to look at some of these complexities is to actually look at some of the core sections. We're gonna start down here because I'm an engineer and my geologists tell me they like to start at the top and go down. But since I'm an engineer I'm gonna start at the bottom and come up. So we have the Three Forks 4th and 3rd Benches which are dolo-mudstones with anhydrite and conglomeratic dolo-mudstones. And this is primarily nonproductive rock. The Three Forks 1st and 2nd benches are highly laminated dolo-siltstones which is our reservoir rock, and it's laminated with the dolo-mudstone which are a non-reservoir rock. Then we come to the lower and upper shales. And if you look at the core this is kind of a black looking shale. They're very organic rich with 10 to 20 weight percent. A total organic carbon which is gonna give you anywhere between 20 to 40% by volume of the rock of total organic carbon content. We have 13 to 40% clay in these rocks, we have some siliceous radiolaria-rich zones from time to time. We have a lot of dispersed K-Feldspar and plagioclase and then we have dispersed pyrite throughout the system. And it only contains anywhere between 2 to 13% carbonate. As far as the middle Bakken we try to break that up into two sections. We have the lower middle Bakken which is a bioturbated siltstone and it's very laminated with sandy-siltstones. And from time to time we have these calcite cemented patches. The upper middle Bakken tends to be very cross bedded, it's fine-grained, well-sorted, and it's a dolomitic sandy siltstone which is very thin-bedded. And finally topping off the system is the Lodgepole Scallion which is a limestone formation. It's a very low porosity in the 2 to 4% range. Doesn't have a lot of storage capacity. But we do see some vertical fractures and I think a lot of these vertical fractures are expulsion fracture. And then we have these rubble zones that we see in the rock from time to time in the pore. So to be able to measure and understand the complexities of this system, we ran a series of advanced logging measurements. These included Induced Capture and Inelastic Gamma Ray Spectroscopy. We ran Triaxial Resistivity logs. We ran Nuclear magnetic Resonance logs. Multi-Frequency Array Dielectric logs. And 3D Multi-component Cross Dipole Sonic.