西南某地岩石蚀变机制及工程地质特性

孙强^{1, 2}，朱术云¹，薛雷²

(1. 中国矿业大学 资源与地球科学学院，江苏 徐州，221116；
2. 中国科学院 地质与地球物理研究所工程地质力学重点实验室，北京，100029)

摘 要：针对制约我国西南地区工程活动的蚀变岩问题，通过对蚀变岩的发育地质环境分析，在结合区域地质条件的基础上探讨蚀变岩成因及演化过程。X线衍射和热分析结果表明：蚀变岩是在特定的地质条件下形成的，其矿物组成大多是长石蚀变后的蒙脱石，其具有较强的吸水膨胀特点。对该地水利工程建设来说，蚀变岩对工程地质特性的影响主要体现在力学强度的改变、变形特性和水文地质条件的劣化。

关键词：蚀变岩带；成因机制；工程地质特性

Genesis mechanism and engineering characteristics of altered rock in southwest China

SUN Qiang^{1, 2}, ZHU Shu-yun¹, XUE Lei²

(1. School of Resource and Earth Science, China University of Mining and Technology, Xuzhou 221116, China;
2. Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics,
Chinese Academy of Sciences, Beijing 100029, China)

Abstract:Altered rock is one of important geological flaws, and analysis on the formation mechanism and physical and mechanical characteristics of altered rock, which can offer reliable evidence to constructions of projects. Taking a hydropower station for example, engineering geological properties of altered rock were analyzed in detail. The result shows that altered rock in southwest China is formed under specific geologic conditions. Based on genesis mechanism and engineering characteristics analysis, the influences of the altered rock are discussed and the main problems which should be studied further are put forward.

Key words:alteration zone; genesis mechanism; engineering geological characteristics