济阳坳陷中生代构造活动与沉积作用的时空关系

济阳坳陷中生代构造活动与沉积作用研究的薄弱增加了这一层位的油气勘探风险,限制了人们对渤海湾地区中生界的精细研究。在济阳坳陷中生界岩心?录井和测井资料的综合分析以及地震资料的综合解释的基础上,研究了中生代构造活动与沉积作用的时空关系。结果表明:坊子期北西向断层较强烈逆冲导致研究区发育时而分割时而相连的山间压陷盆地,沉积?沉降中心靠近北西向断层的东北侧且两者位置的差别较小;三台期北西向断层活动的停止导致研究区发育相互分割的山间坳陷盆地,沉积?沉降中心是一致的;三台晚期到蒙阴早期北西向断层复活并在蒙阴期强烈活动导致研究区发育时而分割时而相连的山间断陷盆地,沉积?沉降中心迁移到靠近北西向断层的南西侧且两者位置的差别较大;西洼期继承了蒙阴期的构造格局,但断层的活动已经有所减弱,沉积?沉降中心位置的差别逐渐缩小。

SPACE-TIME RELATIONSHIP BETWEEN TECTONICS AND SEDIMENTATION DURING THE MESOZOIC IN JIYANG DEPRESSION

There exists high risk for Mesozoic oil-gas resource exploration owing to the lower study of tectonics and sedimentation in the Mesozoic in the Jiyang depression, which restricts the scrutiny of the Mesozoic in the Bohai Bay. According to core observation, mud logging, well logging,and seismic data, space-time relationship between tectonics and sedimentation during the Mesozoic in the Jiyang depression was comprehensively studied. The results show that fault activities controll sedimentary sequences, distribution of lithofacies, sedimentary thickness, and depocenters and subsidence centers. Primarily controlled by the more strong activities of NW overthrusts, intermountain contractional basins sometimes were divided and sometimes were linked together, where the difference between depocenters and subsidence centers near eastnorth sides of northwest faults was smaller and the main sediments were grey fine clastic rocks and red coarse clastic rocks formation, mainly developed during the deposition of the Fangzi Formation.Primarily controlled by paleogeographic environment, intermountain depression basins internally built up by a number of isolated subbasins of various scales, where depocenters and subsidence centers gathered together gradually and the main sediments were red coarse clastic rocks formation, mainly developed for the inactivity of NW faults during the deposition of the Santai Formation. Intermountain fault basins sometimes were divided and sometimes linked together, where the difference between depocenters and subsidence centers near southwest sides of northwest faults was greater and the main sediments were red coarse clastic rocks and grey fine clastic rock formation, mainly developed for rejuvenation and then intensive activities of NW faults during the deposition from late Santai Formation to early Mengyin Formation. Tectonic framework was stable during the deposition from the Mengyin Formation to Xiwa Formation, while the activities of NW faults were greatly weakened, the difference between depocenters and subsidence centers was gradually diminished, and the volcanic rocks were well developed.