渤中坳陷东部新构造特征
NEOTECTONIC MOVEMENT IN THE EASTERN BOZHONG DEPRESSION
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摘要: 渤中坳陷东部地质构造复杂、类型多样,是我国新构造运动最强烈的区域之一,迄今仍是我国东部最重要的震区。该区深部构造特征已被大量的石油勘探资料所揭示,但受分辨率限制,其浅部研究程度仍然较低。本文以渤海最新采集的约2 000km高分辨率多道地震资料为基础,对与新构造运动密切相关的断裂几何学、运动学特征,区域的沉降、沉积中心变迁,天然地震活动特征等进行了详细的分析研究。结合深部及区域构造背景,推断本区新构造运动的形成机制为:走滑应力场叠加深部热沉降的拉张作用。Abstract: The eastern Bozhong Depression is one of the areas with most intense neotectonism in China. There are complex neotectonic structures and types and it is still the most important earthquake area in eastern China.The neotectonic characteristics in the deep part have been disclosed by petroleum exploration, but the features in the shallow part remain unknown due to limited shallow seismic surveys.Based on the 2000km of latest high-resolution multi-channel seismic data,this paper has made a detailed study of the neotectonism in geometry,kinematics,earthquake activities,sedimentation and depocenter migration.According to the deep and regional tectonic backgrounds,it is deduced that the neotectonic movement of the region is a kind of extensional movement resulted from the strike-slip faulting superimposed on the deeplevel thermal subsidence.