巢北栖霞灰岩中的脆韧性剪切构造的研究  

Study on the Brittle-Ductile Shearing Zones in the Qixia Limestone in Northern Chaohu

作　　者：钟建华[1,2] 王德金[2] 戴跃进[2] 王海侨[1] 王志坤[1] 

机构地区：[1]中国石油大学地球资源与信息学院,山东东营257061 [2]中国科学院广州地球化学研究所,广州510640

出　　处：《地质学报》2009年第2期176-195,共20页Acta Geologica Sinica

基　　金：国家自然科学基金项目(编号40272082);973项目(编号2006cb202401)资助的成果

摘　　要：安徽巢北二叠纪的栖霞灰岩中发育了多条小型剪切带。剪切带的宽度介于数十厘米到1m之间,顺层分布。剪切带强烈部位发育了大量方解石脉、强烈片理化及斜歪褶皱。在剪切带中脆韧性剪切构造非常发育,主要有各类剪切面理、S-C组构、线理、斜歪褶皱、眼球构造、柱状构造及其他多种显微剪切构造,其中有的未见报道。研究表明,巢北二叠纪的栖霞灰岩剪切带中脆韧性剪切构造一般是在约3000m深的超浅层发育的,最大深度不超过5500m。地下流体,尤其是有机质成熟过程中排放的有机酸流体促进了方解石在超浅层条件下发生脆韧性变形。Several small brittle-ductile sheared zones developed in the Permian Qixia limestone in northern Chaohu, Anhui, and mainly distribute along the stratum bedding. They range in width from a few tens centimeters to slightly more than one meter. A lot of calcite veins, foliation and inclined folds occur within the intensely shearing parts. Brittle-ductile shearing structures are extremely common in the sheared zones, including sheared foliation, S-C fabric, lineation, inclined folds, eye-ball structure, column structure and some other micro sheared structures, some of which have not been reported up to now. The study reveals that the brittle-ductile shearing zones in the Qixia limestone in northern Chaohu formed at a depth of about 3000 meter below the surface, less than 5500 meters at most. The underground liquid, especially organic acid discharged by organic matter during its maturation resulted in brittle-ductile sheared deformation of the calcite in the extremely shallow condition.

关 键 词：脆韧性 超浅层 流体 灰岩 二叠系 巢北 

分 类 号：P542[天文地球—构造地质学]