辽河盆地大民屯凹陷流体压力特征(英文)

CHARACTERISTICS OF TANLU FAULT ZONE AND DEVELOPMENT OF MESOZOIC AND CENOZOIC BASINS ALONG IT

大民屯凹陷是辽河断陷内 4个下第三系凹陷之一。在综合利用钻井、试井及地震等资料的基础上 ,系统研究并论述了大民屯凹陷流体压力特征。基于 5 7口井的声波测井资料 ,凹陷内泥岩压力特征可区分为正常压力、异常压力或强超压等类型 ;根据 15 2口井 391个点的压力测试数据 ,凹陷内产油层段的压力梯度多接近于 1;利用公式法模拟计算了 4 7条地震剖面的流体压力、剩余压力及压力系数的分布特征 ,凹陷内剖面压力系统自上而下一般由正常压力、弱超压和强超压 3部分组成。此外 ,还根据流体压力演化的基本原理及钻井、岩性与试井等实际资料 ,模拟恢复了大民屯凹陷的压力演化史 ,其可划分为超压原始积累、超压部分释放及超压再积聚 3个阶段。总体上 。

Tan Lu fault zone is a great strike slip structural zone along the Pacific in China,and controls the development and evolution of Mesozoic and Cenozoic basins along it. With the changes in directions of the Pacific plate subduction from NNW to NW and then to NWW,the Tan Lu fault zone motion gradually changed from left lateral strike slip and left lateral oblique slip in Mesozoic to left lateral oblique dip slip in Paleogene and then to dip slip,right lateral oblique slip and right lateral strike slip in Neogene and Quaternary.Due to the changes of the motions of Tan Lu fault zone, the development of basins in Mesozoic and Cenozoic gradually migrated from south to north.The Mesozoic basins are along the middle south segment of Tan Lu fault zone,the Mesozoic and Cenozoic basins are superimposed in the middle segment of Tan Lu fault zone,and the Paleogene basins are along the middle north segment of the fault zone. Each basin has the development evolution of pull apart to inversion. In the same shearing stress field at the same time, the change of the strike gave rise to a local stress change, as a result of that the forced bend saw convergence and uplift, and the pressure release extension bend underwent divergence and subsidence. The basin developed in the extension bend.