济阳坳陷桩海地区的古潜山断裂

FAULT FEATURES OF BURIED HILLS AT ZHUANGHAI, JIYANG DEPRESSION

桩海地区位于渤海湾盆地济阳坳陷北部,由于其处于多个潜山的结合带,有些部位研究力度不够。利用大量最新地震剖面和钻井资料,绘制出该区古生界及中生界沉积残留厚度图,分析了12条断裂的构造特征及其演化。这12条断裂控制了研究区古潜山的构造格局,并对潜山储集性能起着良好的改造作用,使储层沿断裂呈带状分布。桩海地区的构造演化大致经历了印支—早燕山期、晚燕山期和喜山期3个阶段,并于喜山期定型。通过分析认为桩海地区断层多为变换断层,NE向断裂下降盘的古潜山没有油气,而上升盘一侧的构造高点有较好的油气藏,内幕构造圈闭和岩性油气藏也有广阔的前景。

The Zhuanghai area lies in the north of Jiyang depression of the Bohai Bay basin. Because of the particularity of its location, some positions are not well studied. On the basis of comprehensive analysis of some 3D seismic profiles and logging data, the maps of relict thickness of Paleozoic and Mesozoic are drawn in this study. The structural characteristics and the evolutionary process of the twelve faults are analyzed. These faults controlled the tectonic pattern in this region and perfectly improved the reservoir properties of buried hills, making the reservoir distributed along the major faults. Zhuanghai area initially developed in Indosinian period. During the Yanshanian extension and depression, the faulted block formed and uplifted. The present-day geometry was produced in the Himalayan period. According to our analysis, we propose that there is no oil-gas reservoir in the footwall of NE-striking fault and there are many perfect reservoirs in the high points of structures of the hanging walls. Lithologic reservoir and internal structure trap also have perfect prospect.