惠民凹陷沙三期—东营期断裂活动性研究

应用断层落差法,对惠民凹陷沙河街—东营期的断裂活动特征进行了研究.研究表明惠民凹陷古近纪经历强烈的伸展活动,断层活动强烈.凹陷内部的断层主要以北东向为主,断层活动具有分段性的特点,惠民凹陷断层活动形成了多种断裂几何形态.盆地边缘断层和内部断层的活动形成了半地堑、半地垒和地堑—地垒形式的断块体,其断块体组合的分布使整个惠民凹陷具有南北分带、东西分块的分区块断的构造特征.沙三—沙二早期,惠民凹陷处于快速伸展断陷期,中央背斜带隆起,临商断裂带和夏口断裂带活动较强;沙二上—东营组沉积期伸展裂陷活动减弱.经过古近纪断陷期的构造演化,基本确定了惠民凹陷的构造格局.

Study on fault activities in Shahejie-Dongying period in Huimin Sag

The characteristics of the fault activities in Shahejie-Dongying period in Huiming Sag are researched by fault throw method.The results show that the sag goes through intensive extensional activities in Paleogene.The faults in the sag are mostly NE-trending,and the fault activities formed in different periods have segmentation.They have many kinds of geometrical morphologies.The fault activities in the border of the sag and within it form half-graben,half horst and graben-horst faulted blocks,and their combinational distribution makes Huimin Sag possess the structural character of north-south zonation and east-west blocking.During Es3 and the earlier period of Es2,Huimin Sag is rapidly extending faulted stage,its central anticlinal zone heaves and the fault activities in Linshang faulted zone and Xiakou faulted zone strengthen gradually.During Es2 and Ed periods,the extensional faulted activities weaken.The tectonic framework of Huimin Sag is basically formed by the tectonic evolution in Paleogene.