西昆仑北缘冲断带和田段的构造特征

TECTONIC CHARACTERISTICS OF FORELAND THRUST BELT IN HETIAN SECTION,NORTH MARGIN OF WEST KUNLUN

罗金海 何登发

Luo Jinhai He Dengfa

通过对和田一带西昆仑北缘前陆冲断系地表地质构造和地震反射剖面的分析表明,和田前陆冲断系沿走向方向构造形态变化很大。在杜瓦河以东,冲断带的前锋主要发育向北的次级逆冲断层,后者向上消失于断层传播褶皱之中,地表出露的几排背斜就是这些褶皱向上传播的结果;杜瓦河以西,冲断带的前锋主要表现为向南的反冲断层,与整体向北逆冲的铁克里克北缘逆冲断裂构成一个三角带构造。滑脱面深度差异是造成东西方向不同构造形态的主要原因,西段主要沿中寒武统底面滑脱,东段主要沿下第三系底面(或二叠系顶面) 滑脱。

The analysis of the western Kunlun foreland thrust belt in Hetian Region shows that the structural style of the thrust belt changed greatly along its strike.In the eastern part of the Duwa River,its frontal zone consists of 2～3 south dipping second order thrusts that disappeared upwards into the overlying fault propagation fold;in the western part of the Duwa River,its frontal zone is north dipping backthrust which is a part of the triangle zone.The genetic analysis of the thrust belt indicates that the difference of the detachment depths along its strike resulted in different structural styles.The western section detached mainly along the Mid Cambrian sole,but the eastern section detached mainly along the Tertiary sole.

10.11743/ogg19990313