深层碳酸盐岩关键构造-流体演变与成岩-成储——以塔中奥陶系鹰山组为例  

Key Structural-Fluid Evolution and Reservoir Diagenesis of Deep-buried Carbonates:An Example from the Ordovician Yingshan Formation in Tazhong,Tarim Basin

作　　者：李忠[1,2] 李佳蔚[1] 张平童 于靖波[1] 刘嘉庆[1] 杨柳 LI Zhong LI Jia-wei ZHANG Ping-tong YU Jing-bo LIU Jia-qing YANG Liu(Institute of Geology and Geophysics, Chinese Academy of Science, Beijing 100029, China University of Chinese Academy of Sciences, Beijing 100049, China Hangzhou Institute of Geology, PetroChina, Hangzhou 310023, China)

机构地区：[1]中国科学院地质与地球物理研究所,北京100029 [2]中国科学院大学,北京100049 [3]中国石油杭州地质研究院,杭州310023

出　　处：《矿物岩石地球化学通报》2016年第5期827-838,共12页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家自然科学基金项目(41372120;41172096);国家科技重大专项(2011ZX05008-003)

摘　　要：解析系统的构造-流体体制是认识叠合盆地深层碳酸盐岩成岩-成储规律的新思路。针对塔里木盆地塔中下-中奥陶统鹰山组深层碳酸盐岩(深度、温度分别达6500m和220℃)的系统研究表明,其发育6期方解石胶结作用,准同生、表生期胶结及浅埋藏等前三期胶结总体显示与正常海水相关的成岩特征,相比之下中-深埋藏等后两期胶结具有明显的δ13C负值和有机碳输入特征,而热流体胶结物的δ18O、δ13C值均显示相对最大负值。除准同生期选择性溶蚀和表生期溶蚀外,塔中鹰山组主要存在两期埋藏溶蚀,其中第二期除溶蚀早期方解石胶结外,还主要溶蚀白云石,且普遍与烃类注入匹配。研究区关键时期,即中晚奥陶世北西向逆冲断裂、志留-泥盆纪北东向转换走滑断裂、二叠纪张裂及相关流体活动,分别影响了鹰山组碳酸盐岩的岩溶、埋藏溶蚀-胶结等成岩-成储过程。Unified structural-fluid regime identification is a new way to study the diagenesis and reservoir-forming process of deep buried carbonate rocks in superimposed basins.For the Yingshan Formation deep-buried carbonates of the lower-middle Ordovician in Tazhong（up to 6500m,220℃）,Tarim Basin,the research shows that six phases calcite cementa-tion were developed in the carbonates.The former three-phase cements successively formed during the penecontemporane-ous,hypergene and shallow burial stages,with diagenetic features related to normal seawater.In contrast,the later two-phase cements of the middle-deep burial process are characterized by evidently negative δ1 3C values,indicating organic carbon input.Carbonates with maximum negative δ1 8O and δ1 3C values in the fourth cement are related to thermal-fluid flow.Beside dissolution occurred in the penecontemporaneous and hypergene stages,two-phase burial dissolutions devel-oped in the Yingshan Formation carbonates of Tazhong,in which the second burial dissolution mainly resulted from altera-tions of dolomites as well as early calcite cements,coupled with hydrocarbon injection.For the studied area,epidiagenesis and burial dissolution-cementation of the Yingshan Formation carbonates were influenced by the fluid flows that were relat-ed to middle-late Ordovician thrust faults in NW strike,Silurian-Devonian transfer or strike-slip faults in NE strike and Permian tension faults.

关 键 词：构造-流体体制 成岩-成储 深层碳酸盐岩 奥陶系鹰山组 塔里木盆地 

分 类 号：P618.13[天文地球—矿床学]