致密砂岩储层地应力对电阻率测井的影响

库车坳陷克拉苏构造带储层主要为致密砂岩储层，其埋藏深、地层条件复杂，受岩性、应力挤压等因素的影响，使得利用电阻率曲线识别地层流体性质变得比较困难。 基于测井资料，在着重研究地应力大小、方向对该区地层电阻率测井响应的影响等方面，绘制了地层电阻率与地应力交会图，并根据电成像资料统计该区不同区块地应力方向与裂缝走向。 结果表明：随着水平主应力差的增大，地层电阻率呈指数增大的趋势；当水平最大主应力方向与地层裂缝走向夹角较小时，地层电阻率与水平主应力差的相关性较好；当水平最大主应力方向与地层裂缝走向夹角较大时，地层电阻率与水平主应力差的相关性变差。

Influence of ground stress on resistivity logging response in tight sandstone reservoir

Kelasu structural zone in Kuqa Depression belongs to tight sandstone reservoir which is characterized by complex formation conditions and large buried depth. Taking into account the influence of lithology, extrusion stress and other factors, it is difficult to accurately reflect the formation fluid properties by resistivity logging response.Based on studying the influence of magnitude and direction of the ground stress on the resistivity response of reservoir rocks in this area, combined with logging data, the crossplot of formation resistivity and ground stress was plotted, and the statistical data of the direction of horizontal principal stress and the formation fracture orientation in different well fields were sorted by using FMI data. The results show that with the increase of horizontal principal stress difference, the formation resistivity is exponential increasing. The correlation between the formation resistivity and the horizontal principal stress difference is better when the included angle between the direction of horizontal principal stress and the formation fracture orientation is smaller, and the correlation gets worse with the included angle increasing