断层对地应力场方向的影响机理  

Mechanism of faults acting on in-situ stress field direction

作　　者：刘中春[1,2] 吕心瑞[1,2] 李玉坤[3] 张辉[3] 

机构地区：[1]中国石化石油勘探开发研究院,北京100083 [2]中国石化海相油气藏开发重点实验室,北京100083 [3]中国石油大学(华东)储运与建筑工程学院,山东青岛266580

出　　处：《石油与天然气地质》2016年第3期387-393,共7页Oil & Gas Geology

基　　金：国家科技重大专项(2011ZX05014-003);中央高校基本科研业务费专项资金项目

摘　　要：断层附近区域地应力方向相对于远离断层区域存在明显变化。前人利用实验及有限元模拟等手段研究了断层对其附近区域地应力方向的影响规律,但是缺少从力学机理角度解释这些规律的研究。研究总结了单一断层附近最大水平主应力方向变化规律,利用孔口问题弹性力学解析解揭示了这种规律的力学机理,并以某单元为例,研究了多断层区域最大主应力方向沿断层走向上的变化。结果表明,断层端部区域最大水平主应力朝着断层走向偏转,应用孔口问题弹性力学求解可以获得理论证明,塔河某单元的地应力计算结果也验证了这种规律。Direction of in-situ stress near a fault is significantly different with that far away from the fault. Experimental approaches and finite element simulation method were previously used to study the patterns of faults acting on in-situ stress field direction, but these patterns were never explained in respect of mechanical mechanism. The regularity of elas- ticity mechanical mechanism were reveals by using the analytical solution of elliptic orifice problems based on study of the change patterns of the maximum horizontal principal stress direction near a single fault. And a block was taken as an ex- ample to study the change of the direction of maximum principal stress along fault strike in areas with multiple faults. The results show that the maximum horizontal principal stress deviates to the fault strike at the ends of faults. The phenomenon can be well explained with the aid of orifice problem of elastic mechanics analytical solution. The calculation results of in- situ stress in one unit of Tahe oilfield also verify the rule.

关 键 词：椭圆孔口问题 地应力 断层 塔河油田 

分 类 号：TE122.1[石油与天然气工程—油气勘探]