郯庐断裂(K2-E)的伸展活动及其对合肥盆地的控制

郯庐断裂带于晚白垩世 -老第三纪 (K2 -E)时期卷入了广泛的伸展活动 ,其伸展结果是沿着早期先存的走滑断裂产生了伸展正断层 ,构成了合肥盆地的东缘断陷边界。在断裂的西侧控制了合肥盆地上白垩统 -下第三系的同沉积可容空间 ,而断裂东侧张八岭隆起进一步抬升 ,由此形成合肥盆地充填的物源系统。与此同时 ,盆地内先存近东西向逆断层也相应产生了伸展活动 ,并控制了盆内近东西向的沉积。在伸展断陷盆地内均有明显的沉积响应。文章从合肥盆地 K2 -E的沉积响应特征探讨郯庐断裂带伸展期对合肥盆地的控制机理 ,提出了该阶段盆地的沉积可容空间受双向伸展断裂的控制模式

Extensional activites of the Tan-Lu fault zone from the late Cretaceous to the Palaeogene and its controlling for the Hefei basin

The extensional activities along the Tan Lu fault zone occurred in the period between Late Cretaceous and Palaeogene,and the extensional normal faults were formed along the preexisting strike slip faults.These extensional normal faults formed the faulted boundary of the eastern edge of the Hefei basin. On the western side of the faults, they controlled the synchronous depositional space of the upper Cretaceous series and Palaeogene system, and on the other side of the faults,the Zhangbaling uplift was raised further. Thus, the material source system of the Hefei basin were formed,and the extensional activities along the preexisting E W trending thrust faults also occured in the basin and they controlled the nearly E W trending sedimentation. There were obvious depositional response in the extensional faulted basin. Based on the analyses of the depositional response,the controlling mechanism for the Hefei basin is discussed,and it is advanced that the model of the depositional space of the Hefei basin is that the depositional space was controlled by the dual extensional faults.