低电阻率油层研究现状

Recent researches on low resistivity pay zones

在详细分析低电阻率油层形成机制的基础上,总结了中外对低电阻率油层研究的现状。低电阻率油层主要分为内因、外因和复合成因3类,内因包括油层中含有高矿化度地层水、油层中含有较多的束缚水、粘土附加导电性、油层微孔隙发育、岩石骨架导电及岩石强亲水等;外因包含钻井液的侵入,油、水层对比条件发生变化,深侵入与测井探测范围有矛盾等;既有内因作用也有外因作用的则为复合成因。其评价和识别方法主要分为定性和定量2个方面。评价时应采取定性和定量方法相结合,并且与成因机制相匹配,由浅入深、从简单到复杂,逐步识别低电阻率油层。

Based on thorough analysis of the forming mechanism of low resistivity pay zones, recent researches on the low resistivity pay zones axe reviewed. There are inherent,exterior and multiple origins of the formation. Inherent origins include high-salinity formation water and more bound water in the pay zones, electric conductivity added on clay,developed micropore in pay zones,e-lectric conductivity of rock framework as well as strong water wetting of the rocks etc. Exterior origins consist of invasion of drill fluid,change in correlation conditions between oil and water formations, contradiction between deep invasion and logging detection range. Multiple origins are combined inherent origins with exterior origins. Evaluated and discriminating methods are from two aspects of the qualitative and quantitative analysis, which are combined adequately, and are suitable to forming mechanism. We should discriminate the low resistivity pay zones step by step from simpleness to complexity.