江汉盆地西南缘主干断层活动性分析

江陵凹陷的形成与发育过程非常复杂,经历了多期构造运动.文中分析了江汉盆地西南缘的构造背景及断裂发育特征,复兴场、谢凤桥等主干断裂是该区构造的主要控制因素,通过选取5条垂直于断层的剖面进行三维地震解释,认为它们具有同生断层的特点.讨论了生长指数研究断层活动性的局限性,用生长指数和断层活动速率,从空间和时间上,对该区主干断层的活动性进行了研究,结果表明断层活动速率更能反映出断层活动性.

An Analytical Study of the Activity of Main Faults in the Southwest of Jianghan Basin

Jangling depression, whose formation and development are very complicated, underwent multistage tectonization. By analyzing structure background and the development characteristics of the southwest of Jianghan basin and by choosing five section planes, which are vertical with these faults, for 3D seismic interpretation, it can be found that such main faults as Fuxingchang fault and Xiefengqiao fault control the regional structure and they are synsedimentary faults. The dimensional and temporal development characteristics of the main faults are studied both through growth index and fault activity ratio. It is indicated that the fault growth index cannot precisely reflect the actual fault activity. It has been proved that the fault activity ratio is fit for better analysis and study of the formation and development of the faults.