四川甘孜楞古地区褶皱构造特征及形成机制

THE CHARACTERISTICS AND FORMATION MECHANISM OF FOLD IN LENGGU AREA OF GANZI,SICHUAN

经历印支期、燕山期及喜马拉雅期构造运动而形成分布在区域范围内的三期三方向褶皱。大比例尺填图及构造解析表明,区内以第一期褶皱——孜河-楞古背斜为主体,构成区域整体格架,表现出近东西向弧顶向南突出的弧形特征,较好地反映了"双向俯冲"的板块动力学模式。

The Lenggu area, in the core part of Songpan - Ganzi fold zone, has experienced of Indosinian, Yanshanian and Himalayan tectonic movement, which cause the fold development, ie the foNnation of 3 periods of folds in this area. The large scale mapping and structure analysis show that the 15, period fold--Zihe - Lenggu anticline as a main part forms the general framework of this area, which shows the southward sticking out arc characteristies of nearly EW - ward are top, reflects clearly the dynamic model of plate ＂two - way subduetion＂.