一个低电阻率油气藏的测井评价

根据J油田大量岩芯分析资料,应用油藏流体分布理论和毛管压力计算方法,研究该油田低电阻率油气层的形成原因认为:地层水矿化度高(多数>20万ppm);微细孔隙发育,束缚水含量高;粘土矿物含量高且分布在碎屑颗粒表面等是形成低电阻率油气层的主要原因.一般常规测井评价时,对这种低电阻率油气层容易误释而丢弃.依据油气藏流体分布原理,应用毛管压力方法计算原始含油饱和度,可准确地识别出这种低电阻油气层,并可预测其产能.

LOG E-VALUATION METHOD FOR AN OIL/GAS RESERVOIR WITH LOW RESISTIVITY

Based on large amount of core analysis data and by using the fluid distribition theory and capillary pressure method, the formation of low resistivity layers of this oil field is studied. It is believed that the high salinity of formation water (greater than 200000 ppm), the development of micro-pores, high bound water, high clay mineral content and distribution on elastics surface of clay minerals are the main causes resulting in low resistivity oil/gas reservoirs. This type of low resistivity layers could be easily ignored by conventional log evaluation method. This kind of low resistivity oil/gas zones can be accurately identified and their potential can be predicted by using fluid distribution theory and capillary pressure method for original oil saturation.