某地区长_8中高电阻率储层出水原因分析及其应用

Causation Analysis of Water-out from a Chang-8 High Resistivity Formation and Its Application

鄂尔多斯盆地某地区长8砂体发育,厚度大,岩心大都有油斑,测井电性为中高电阻率（30-150Ω·m）,常规解释结论多为油层或油水层。但压裂改造后试油结果却大都产水,测井解释符合率极低。通过对地质、测井和试油等资料的对比,从储层物性、岩心、地层水及原油性质4个方面分析了该区长8中高电阻率储层出水原因,提出了常规测井和核磁共振测井综合识别中高电阻率水层的解释方法,完善了该区的解释图版,提高了长8储层测井解释准确度,取得了良好的应用效果。

Drilling result of Chang-8 formation in a district, Erdos Basin, showed that the formation was characterized with matured sand body, large thickness, and oil-spotted core, and its logging electricity showed medium or high resistivity （30-150Ω·m）, so that conventional interpretation conclusion would like to be as oil bearing zone or oil-water bearing zone. But after fracturing, most of the reservoirs produced water in well testing, the interpretation accordant rate was very low. Through comparing data of geology, logs and well tests, and analyzing the causation of water producing from the reservoir based on its characters of petrophysics, core, formation water and crude oil, resulted in are an interpretation method combining conventional and NMR logs to identify water layers with medium or high resistivities in Chang-8, as well as its improved interpretation charts of the district. It improves the interpretation accuracy of Chang-8 and gets good applicable effectiveness.