海西构造旋回阴山幕式造山与鄂尔多斯盆地北部旋回充填的耦合关系

摘要

This paper discusses the relationship between the filling rule of the sediments in Ordos Basin and the Yinshan Orogenic Belt to provide an example for the coupling relationship between orogenic belts and large craton basins.In analyzes the sedimentary sequences of 9 sections and 133 classical drilled wells of Late Permian in the north of Ordos Basin are researched.The results indicate that there exist three significant sedimentary filling cycles of coarse grained-fine grained-coarse grained sediments in the Taiyuan-Shanxi,Shihezi and Shiqianfeng periods.The key time nodes of violent orogenic activities and basin subsidence are calibrated accurately as 285,274 and 256 Ma B.P.by the analysis of the tectonic subsidence history. These three time nodes are corresponding to the sedimentary transformation of progradation-retrogradation in the Taiyuan-Shanxi, Shihezi and Shiqianfeng periods.This shows that the episodic orogenic movement of the Yinshan ancient land caused by the subduction-collision orogeny between the North China plate and the Siberian plate is closely coupled with the filling cycles of the basin.%探讨鄂尔多斯盆地沉积物充填规律与阴山造山带间的相互关系，为大型克拉通盆地沉积充填规律与造山带耦合关系提供实证。通过鄂尔多斯盆地北部晚古生代9条野外剖面和133口典型钻井详细的沉积充填序列分析，结果清楚地揭示晚古生代太原-山西期、石盒子期、石千峰期存在明显的3个由粗-细-粗的沉积充填旋回。构造沉降史分析准确标定出285 Ma B．P．、274 Ma B．P．和256 Ma B．P．为造山活动加剧、盆地强烈沉降的时间节点，而这3个时间节点正好对应于太原-山西期、石盒子期、石千峰期3个时期内退积-进积的沉积转换，这说明海西期华北板块向西伯利亚板块俯冲-碰撞造山所导致的阴山古陆的幕式造山运动与盆地的旋回充填存在密切的耦合关系。