水力压裂地应力测量有关技术问题的讨论

DISCUSSION ON TECHNICAL PROBLEMS RELATED TO MEASUREMENT OF EARTH STRESS THROUGH HYDRAULIC FRACTURING

葛洪魁 林英松 王顺昌

Ge Hongkui Lin Yingsong Wang Shunchang

石油大学华东石油工程系 石油地球物理勘探局

利用水力压裂可获得最小水平地应力的大小和地应力方向。最小水平地应力的数值近似等于水力压裂裂缝闭会压力,但由于套管的存在,不能用套管井压裂数据计算最大水平地应力。在钻井过程中进行地应力测试可在勘探早期获得地应力数据,并用于指导后期的勘探开发工作。斯仑贝谢公司MDT模块式地层动态测试仪和哈里伯顿公司的井下应变仪是比较先进的地应力测试工具。分析了测试层住筛选、使用仪器、施工方案及精确的施工曲线分析等影响地应力测试精度的有关问题,并对进一步开展地应力测量工作提出了建议。

The scale of the minimal horizontal earth stress and the direction of the earth stress can be obtained from hydraulic fracturing. The value of the minimal horizontal earth stress equals approximately to the closure pressure of fracture formed through hydraulic fracturing. Yet, owing to the existence of the casing, the maximal horizontal earth stress can not be calculated from fracturing data of casing well. lf earth stress is tested in the course of drilling, the earth stress data can be obtained at the early stage of exploration,which is very helpful to the direction of the later exploration and development. This paper analyzes the factors influencing the accuracy of measuring the earth stress:the tested formation, the applied instruments, the operation plan, the analysis to the operatlng curves and so on. Further more, this paper puts forward proposals on how to further conduct well earth stress measurement.

10.3969/j.issn.1000-7393.1998.06.017