山东惠民凹陷古近系基山砂体地震作用成因新论

通过岩心观察和成像测井资料分析,对惠民凹陷中央隆起带古近系基山砂体成因进行了研究,笔者首次提出惠民凹陷中央隆起带基山砂体沉积动力学机制为地震作用而非洪水沉积。基山砂体主要由原地震积岩(原地地震扰动层)、“似海啸岩”(准原地)、及震浊积岩(异地)组成,在此基础上,建立了相应的地震沉积序列和震积作用模式。地震扰动层对识别基山砂体的地震成因十分关键,震浊积岩构成基山砂体的主体,两者之间为一规模不等的震积不整合面。研究结果表明,基山砂体与超浅成侵入岩共生,地震是由深部岩浆的上拱引起,中央隆起带地震事件与岩浆侵入事件具有同时间和同空间性。

New Demonstration of the Seismic Origin for Jishan Sandbody of Paleogene in Huimin Depression, Shandong Province

The Jishan sandbody of central uplift belt of Paleogene in Huimin depression has been studied in terms of core observation and image logging datum analysis.The results show that the sedimentary dynamic mechanism for Jishan sandbody is seism,rather than flood deposition.Jishan sandbody is mainly composed of seismites(seismically disturbed),similar tsunamites and seismoturbidite rocks.A corresponding seismic sedimentary sequence and model have been established.The seismically disturbed series is crucial for analyzing the origin of Jishan sandbody,and the seismoturbidite rocks are the main body of the series.Both layers are contact with seismic unconformity plane of varied scale. During early Sha-3 period,the seismic events are resulted directly from magmatic intrusions and the upward of deep magma in origin.Magmatic intrusions and seismic events happen simultaneously at the same time and space.