准噶尔盆地南缘地应力分析及相关问题探讨

准噶尔盆地南缘西部水平最大应力方向为NNE向，中部为NS向，东部为NNW向或NW向，残余构造应力、现今构造应力、地层埋深、岩性等是地应力场的主控因素．在分析地应力特征的基础上，探讨了其对地层异常压力、油气分布及钻井工程的影响．较强的应力作用使断层具有较好的封闭性，促使油气的运移和富集，上部地层的异常高即可以作为储层的盖层，也可以形成异常高压储层，这些都利于油气藏的形成．然而地层异常高压和较强的应力作用使该地区油气钻探带来相当大的困难．

ANALYSIS OF GROUND STRESS IN THE SOUTHERN PART OF JUNGGER BASIN AND DISCUSSIONS OF THE RELATED ISSUES

The direction of the biggest horizontal stress in the southwestern part of Jungger Basin is NNE, and that in the central part is SN, that in the eastern part is NNW or NW. Remained tectonic stress, present tectonic stress, depth of the layers and lithology are the main factors that control the present tectonic stress field. We discussed the impact of tectonic stresses on the occurrence of abnormal pressure, the distribution of oil and gas and drilling process on the basis of analysing the present tectonic stress field. Relatively high tectonic pressure is in favor of the closing of the opened faults, and the overpressured upper layers suggest that the underlying reservoirs are well capped. However, overpressured layers and high tectonic pressure will cause significant difficulties in drilling processes.