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  5. Refracking And Sweeping Sweet Spots

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- [Voiceover] Right now many of our fields are mature, and they are in need of a water flood or CO2 flood, and refracs can be really, really util in preparing the reservoir for effective sweep. So, you can have a refrac in a reservoir that is going to have a water flood, and the reason for it would be to increase the induced fractures, and also, if you use acid in some cases, clean it out and allow the new conduits to create pathways and flow, and avoid some of the areas that have just been channelized, and also you could refrac ahead of a new transition zone dewatering operation. You can use, quote, smart nanosurfactants to like maximize the contact with the surface, reduce the surface tension and get a lot of oil, and some gas, but mainly oil, flows through with a lot of water. So, in that case, you want a lot of water. It's interesting, in speaking of different types of EOR, refracs in conjunction with a sweep in which you're trying to optimize the contact with surface spaces or poor spaces, in order to liberate the oil that's kind of resistantly sticking there, not coming out, or it's resistant because it's been in closed fractures and in closed poor spaces. Essentially, there are two things. We want to refrac a few of the vertical wells in the middle of the field, potentially, and create new conduits, or you might want to drill a horizontal to create conductive fractures, and then one thing you're injecting water, or CO2 into the injection wells, and you're optimizing your sweep by using some strategic refracturing. A second type of sweep is dewatering. We talked about it a little bit earlier. An example is the Hunton in Oklahoma. You could refrac some of the Huntons to, like, optimize the movement of water, massive, massive volumes of water with, say, one to three percent oil cut, maybe five percent in a really great area, and that flows through and then it's separated. Now, the water is your friend in this case, because water in conjunction with smart nanosurfactants it helps you sweep out the hydrocarbons. Water isn't so much your friend once it becomes produced water. That's another story. Anybody who can load balance injection wells and help reduce the amount of induced seismicity would be, like a hero, especially if they can do it almost for free. At any rate, refrac vertical wells, some people advocate a five-spot pattern, nine spot, whatever. Injection wells include, it's a extreme nanosurfactants, extremely effective new surfactants. What refracs do is they help create more surface area, and the surfactants essentially reduce the surface tension and liberate the hydrocarbons, mainly oil, from where they're clinging to the surface or the edges of the reservoir, clinging to the rock, and so, it helps them get slippery, and flush right out and sweep right out of the reservoir. So, refracs can liberate the water and help with the sweep, help push that oil out.