某地区白云岩室内溶蚀试验及微观溶蚀机理研究  

LABORATORY DISSOLUTION TEST ON DOLOMITE AND ITS MICRO-DISSOLUTION MECHANISM

作　　者：张良喜[1,2,3] 赵其华[1,2] 胡相波[4] 韩刚[1,2] 赵幸[1,2] 

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,成都610059 [2]成都理工大学环境与土木工程学院,成都610059 [3]四川省地质矿产勘查开发局攀西地质队,西昌615000 [4]中水北方勘测设计研究院有限责任公司,天津300222

出　　处：《工程地质学报》2012年第4期576-584,共9页Journal of Engineering Geology

基　　金：长江学者和创新团队发展计划项目(IRT0812);国家重点基础研究发展计划项目(2011CB013501)资助

摘　　要：揭示白云岩溶蚀砂化形成机理。开展室内不同溶液条件、不同结构白云岩溶蚀试验,对比分析溶蚀速率控制因素,采用铸体薄片、扫描电镜分析不同溶蚀阶段白云岩微观结构变化特征。结果表明:岩石微观结构对溶蚀速率起控制性作用,不同结构白云岩溶蚀速率关系为:中-细晶白云岩>细-粉晶白云岩>粉-泥晶白云岩;比表面积与总溶蚀量有关,与单位面积溶蚀速率无关;溶蚀起始于粒间、晶间孔隙、构造微裂隙与解理,并逐步扩展使孔隙、裂隙相互连通;溶蚀使白云岩微观结构逐步劣化,晶体联结力减弱,伴随晶体崩解脱落,最终分解成细小颗粒而形成白云岩溶蚀砂化。This paper reveals the dissolution gritty mechanism of dolomite. Some dissolution tests are carried out Under different solution conditions and dolomite structures to analyze the factor of dissolution rate. It uses the casting thin sections and the scanning electron microscope methods to analyze the microstructure of dolomite at different dissolution stages, the test findings are that ： （ 1 ） the rock microstructure dominates dissolution rate. The relations of different dolomite structures with its dissolution rate rateare as follows： （a） the dissolution rates for medium-fine grain dolomite, fine-powder crystal dolomite and powder dolomierite are greatest and medium and lowest, respeetively ; （2） Specific surface area is connected with the total dissolution amount but not the dissolution rate in unit area; （3）the dissolution starts at the inter grain, the inter crystal void, the tectonic micro-fracture and the cleavage.It extends gradually to make sure that the voids and fractures are connected each other; （4）the dissolution worsens the microstmcture of Dolomite gradually, weakens the connecting force of crystals. It couples with the disintegration and falling off of crystals. And finally it breaks up into fine particles and results in the gritting of dolomite.

关 键 词：白云岩 溶蚀砂化 溶蚀试验 溶蚀速率 岩石微观结构 

分 类 号：P642[天文地球—工程地质学]