西准噶尔达尔布特断裂南东缘红山岩体“拖尾”构造的成因探究——基于石英EBSD组构的分析

A Discussion on the Origin of the"Tuowei"Structure of the Hongshan Rock Mass on the Southeastern Margin of the Darbot Fault in Western Junggar--Based on the Analysis of the Quartz EBSD Fabric

通过地质填图厘清了达尔布特断裂为形成于晚石炭世晚期的左行走滑断裂,红山岩体侵入于晚石炭世早期,前者左行错移改造红山岩体形成了“拖尾”构造。采用野外观察达尔布特断裂伴生构造和红山岩体中发育的剪切构造特征,与基于岩体碱长花岗岩石英EBSD组构测试分析相结合的方式对红山岩体“拖尾”构造的成因进行探究。探究结果表明,红山岩体“拖尾”变形构造是达尔布特断裂左行走滑脆性剪切错移红山岩体所致。

Through the project mapping results,this study clarified that the Darbot fault is a left strike slip fault formed in the late Late Carboniferous,and the Hongshan rock mass was intruded in the early Late Carboniferous.The former left strike offset transformed the Hongshan rock mass to form a"tailing"structure.The origin of the"trailing"structure of Hongshan rock mass is explored through the field observation of the associated structure of Darbout fault and the shear structure characteristics developed in Hongshan rock mass,as well as based on the test and analysis of the alkali feldspar granite quartz EBSD fabric of the rock mass.The research results show that the"tailing"deformation structure of the Hongshan rock mass is caused by the left lateral strike slip brittle shear dislocation of the Hongshan rock mass in the Darbot fault.