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  5. Discussion & Summary

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- [Holger] So before I go into the summary of the talk, I'd like to point out a few things on the methodology that we have been presenting here. I guess as some of you may already have thought about some of these different effects that we've presented, they can actually cause a similar mismatch or deviation between anabolic water and the total water from resistivity. Our experience however is that, we were so far, pretty much always able to eliminate the unreasonable effect and boil this down to the effect that really plays a role for these different reservoir scenarios and then of course you may also want to argue well multiple effects could possibly occur jointly and yes that's right but again in the cases that we have been looking at so far, it's primarily one of the effects being predominant and we really haven't gone through the challenge of identifying and quantifying multiple of these effects. That of course will be something for, for some future work and will be some additional challenge. Some other aspects which we didn't present in much detail is some geometric limitations or geometric effects of the different measurement principles. We talked about the invasion of the investigation effect but there is of course also difference in the resolution of the animar versus the resistivity tools and they can be quite of interest especially in high angle horizontal wells, where bed boundary effects are more of interest. In particular, the resistivity measurements can be affected by near by beds, in particularly conductive beds, as well anisotropy, and on the animar side you need to look out for borehole enlargements which can also effect the measured response. Also, we certainly acknowledge that, the examples and effects that we discussed here, are by far not all of the effects that are relevant for petro-physical analysis of reservoirs. So there are a number of other joined applications, using animar and resistivity you can think of. One area, certainly the area of unconventionals, where I'm sure you don't want to only use animar and resistivity but whatever tool you have available to do some integrative interpretation and there by get the best possible results from your interpretation. Another area is using resistivity images, high resolution, information for improving thin bed analysis, in conjunction then with the more bulk measurement of an animar device. Other effects are the established correlations between cation exchange capacity of shales, and the clay bound water associate with the shales, so there are opportunities to do better characterization of the shales and shale effects, and last but not least, there is a known analogy between electrical current and fluid flow through the pore space, and that is certainly an interesting area, to yes, spend a few more thoughts and efforts, on to, learn a little bit more about the connections there. With that, I'd like to, summarize our presentation here, so we have been showing how we envisage combination of animar and resistivity fluid volumetrics, where maybe to best remember is the animar actually differentiates the bound vs. movable fluids, and the resistivity differentiating conductive vs. non-conductive fluids, and that comparison is really the baseline of most of the comparisons that we have been doing, in the context of this presentation, and then we presented the application of this approach for identifying water production, mud filtrate invasion, Archie parameter adjustment, heavy oil and tar application, wettability alteration, and magnetic minerals, just as a little bit of a disclaimer, these things of course you should first do all your proper standard petrophysical evaluation, all your corrections and so on, before you start going into exploring these effects in more detail, and ultimately, the outcome of this exercise, you can apply for real-time application, starting from drilling pressure management, down to reserve estimations, reservoir modelings, down to completion and production decisions. And with that we'd like to acknowledge, Gary Ostroff for a lot of insightful discussions and a critical review of the paper. Baker Hughes for the permission to present the work, and SPWLA for the selection of the paper and the opportunity to present it as a Distinguished Speaker presentation.