宁镇山脉印支—燕山早期的滑脱拆离构造

ON THE GLIDING-DECOLLEMENT STRUCTURES DEVELOPED DURING INDOSINIAN-EARLY YANSHANIAN EPOCH IN THE NINGZHEN MOUNTAIN RANGE

宁镇山脉海相中、古生界沉积盖层内部存在多层滑脱系统。在印支-燕山早期,由于区域性的重力和后推力的作用,沉积盖层沿不同滑脱层经过连续的、递进的滑脱变形形成了滑脱拆离构造,主要型式有:箱状褶皱构造、顺层滑脱构造及褶皱-逆冲构造。滑脱拆离构造的动力模式主要有两种:即印支期的以滑覆为主、推覆为辅的动力模式和燕山早期的以推覆为主、滑覆为辅的动力模式。

The gliding-decollement systems at multiple levels took place within the Mesozoic-Palaeozoic marine sedimentary sequences. During Indosinian-Early Yanshan,due to first regional gravitation and then pushing-compression occurred in the area,the continuous and progressive decollement-defor-mation developed along different horizons within the sedimentary sequences,bringing about gliding decollement structures. The main patterns of the structure are of box-foldings,decollement along the horizons,and folding-overthrustings. In this paper,it is proposed that there are two models for the gliding decollement structures,i, e. decollement with overthrusting during Indosinian epoch and over-thrusting with d. ecollement in Early Yanshan.