沾(化)车(镇)地区滚动背斜研究

ORIGINAL ANALYSIS OF ROLLOVERING ANTICLINES AT ZHANHUA\|

从构造和沉积两方面研究了沾车地区滚动背斜的形成机制。在构造方面，主要包括断层的几何学特征、运动学特征和动力学特征与滚动背斜的关系；在沉积方面，主要包括沉积速率和沉积物的性质。从断面几何形态上看，铲式断面可引起层面的反倾，上凸断面可以形成鼻状构造或滚动背斜，而坡坪型断面则易于形成滚动背斜；从运动学特征上看，大的伸展量和大的断层滑动速率是形成滚动背斜的有利条件；从断面的力学性质上看，张性正断层则易于形成短轴背斜，更易于形成圈闭。从沉积学角度看，形成滚动背斜应以不太大的沉积速率为宜，但不能给出绝对值，因为必须考虑下盘与上盘沉积速率的比值，岩性则以砂泥岩互层最为有利。另外。

ollovering anticlines developed well in Paleogene System of Zhanhua\|Chezhen area in the north of Jiyang Depression in Bohai Bay Basin. The forming mechanism of the anticlines is analyzed in terms of tectonics and sedimentology. In tectonics, the relationships of fault geometry, kinematics and kinetics to the anticlines are discussed, and in sedimentology, the deposite rate and the characteristics of sediments are described. Listric faults can cause antithetic bedding tip, and convex faults can form nose\|typed structures and/or rollovering anticlines. Flat\|ramp faults are conductive to form rollovering anticlines. Kinematically, large extension and slip rate are favourable to form rollovering anticlines. Kineticly,tensional faults can form large cylindric rollovering anticlines, and strike\|slip normal faults can form short\|axis anticlines. In the view of sedimentology, the conditions favorable to form rollovering anticlines are interbedding of sandstones and mudstones without too large sedimentary rate. Certain original tip and differential compaction are needed in some cases.\=