川东北地区晚二叠世碳酸盐岩成岩作用  

Diagenesis of Late Permian carbonates in northeastern Sichuan

作　　者：罗雷[1] 洪天求[1] 殷延端 李孝才 任鑫鑫[1] 杨梅[1] 

机构地区：[1]合肥工业大学资源与环境工程学院,安徽合肥230009

出　　处：《合肥工业大学学报（自然科学版）》2017年第1期101-109,116,共10页Journal of Hefei University of Technology：Natural Science

基　　金：国家自然科学基金资助项目(41072085);合肥工业大学博士学位人员专项基金资助项目(JZ2016HGBZ1043)

摘　　要：川东北地区晚二叠世碳酸盐岩广泛发育,成岩作用的类型和过程复杂。薄片镜下鉴定显示该区碳酸盐岩内发育泥晶化作用、溶解作用、白云石化作用、压溶作用和破裂作用5种主要的建设性成岩作用和压实作用、胶结作用、去白云化作用、硅化作用、重结晶作用和充填作用6种主要的破坏性成岩作用。成岩作用特征和碳氧同位素分析表明,研究区存在海底、大气淡水、埋藏和表生4种主要的成岩环境和准同生-同生期、早期、中期、晚期成岩阶段及表生成岩阶段,不同的成岩环境和成岩阶段分别发育不同的成岩作用。在成岩作用的影响下发育较高的孔隙度,主要集中在长兴组的生物礁灰岩内及白云岩内,孔隙连通性也较好,是油气生成、运移和储集的有利通道和场所。The Late Permian carbonates are widespread in the northeastern Sichuan Province, and the process and types of their diagenesis are complex. Microscopic examination shows that there are five major constructive diagenesis, such as micritization, dissolution, dolomitization, pressure solution and tectonic rupture, and six types of destructive diagenesis, such as compaction, cementation, ded- olomitization, silicification, recrystallization and filling. Combined with the C-O isotope analysis, four main diagenetic environments can be recognized in this area, including marine, meteoric, burial and surface environments. The sediments have experienced syngenetic-quasi syngenetic stage, early, mid- dle, late diagenetic stage and epidiagenetic stage. Different diagenetic environments and diagenetic stages were responded to different diagenesis. The carbonates of the studying area developed high po- rosity because of the effect of diagenesis, which are mainly seen in the bioherm limestone and dolomite of Changxing Formation. The extensive porosity and connectivity make the carbonates in this area be- come the ideal place for generation, storage and migration of the gas and oil.

关 键 词：成岩作用 成岩阶段 碳酸盐岩 晚二叠世 川东北 

分 类 号：P586[天文地球—岩石学]