摘要
本文通过对宁镇山脉构造特征的分析,认为宁镇山脉是由三个自南而北推掩的构造片体组成的推覆构造。每个构造片体的表层褶皱与逆冲、逆掩断裂组合都是深层滑移的地面表象,反映了统一的构造应力场。推覆构造的主体北东东向延伸,略呈向北突出的弧形,主要形成于三叠纪晚期的印支运动即南象运动。属于扬子、华北两个古板块碰撞带的后缘构造。燕山中—晚期北北东向挤压构造对其产生横跨和叠加。
Through one-year(1984 to 1985)of detailed field observation of the structure of the Ningzhen mountains. I divided the mountains into three thrust sheets pa-shing from south to north and the folds developed in these sheets were but surface appearance of the deep seated slipping. The folds, over thrusts and thrust faults reflect an unigue tectonic stress field. The northward projecting arcuate structure should be considered as the front structure of Ningzhen terrene thrusting northward during the Indo-Chinese Movement in the lata Triassic,namely,the Nanxiang Movement.After having investigated in the Mts. Qixia and Nanxiang in detail, it is clear that the high angle unconforimty between Xiangshan Formation (J1-2xn) of the Lower Jurassic and the underlying strata including the whole segnece ranging from Devonian system to Lower Triassic Qinglong i'ormation(T11x)implys that the Indo chinese Movement had taken place in lower Yangtze area and further more that the movement was very strong in that region. The basic structural patterr of the mountains comprises largcscale NEE trending recumbent and overturned folds and thrust-over-thrust assemblage, which were formed mainly during the Indochinese rather than the Yanshan movement. The generation of the Indochinese Movemten and the formation of the structures should be attributed to the collision of North China plate with the Yangtze plate. The structures should represent the back structure of the collision zone which were crossed and superimposed by NNE trending structures during the middle-late phase of Yanshan Movement.This paper discusses the following subjects.(1) the structural model of the Ningzhen mountains; (2)the formation of the Ningzhea nappe structures.
出处
《吉林大学学报（地球科学版）》
EI
CAS
1987年第2期143-154,共12页
Journal of Jilin University：Earth Science Edition
