摘要
塔里木盆地英买力—哈拉哈塘地区奥陶系碳酸盐岩岩溶型储集层获得勘探突破,对研究区成岩作用及孔隙演化的研究具有重要意义。通对对大量的岩心、薄片、阴极发光、成像测井及测试分析等资料进行综合研究,认为研究区岩溶储集层经历了多期多类复杂的成岩作用,其中溶蚀(或岩溶)作用、破裂作用、压溶作用使原岩产生大量次生孔隙从而改善其储集性,为建设性成岩作用;胶结充填作用和硅化作用降低了碳酸盐岩的原生和次生孔隙度,为破坏性成岩作用;热液作用具有双重作用。岩溶储集层经历了(准)同生期和早成岩期海底成岩、近地表成岩及浅埋藏成岩阶段,后受加里东中、晚期—早海西期构造运动影响,遭受了几期长短不一的暴露溶蚀,其后经历了中、晚海西期的波动性埋藏及中、新生代的浅—深埋藏成岩阶段,构成了中期间隙开启型成岩演化系统。相应地,孔隙演化经历了原生孔隙形成—缩减期、缝洞发育期、缝洞缩减充填期和裂缝、埋藏溶蚀—充填期4个阶段。原生孔和早期溶孔大部分被胶结充填,不构成有效储集空间;加里东中、晚期—海西早期岩溶作用对研究区储集空间的形成具有决定性作用,溶蚀孔、洞、缝和构造破裂缝构成了英买力—哈拉哈塘地区碳酸盐岩岩溶储集层主体;深埋溶蚀作用对先期储集层改造调整,进一步增加了储集层的非均质性。
A breakthrough was obtained in the Ordovician carbonate karst reservoir of the Yangimahalla-Hanilcatam region in the Tarim Basin which has great influence on the diagenesis and pore evolution.Based on the cores,the normal thin sections,the cast thin sections,the cathodoluminescence,the FMI and the testing data,the Ordovician carbonate karst reservoir of the study area experienced superimposed and multi-stages diagenesis.They could be classified into two sorts：constructive diagenesis and destructive one.The constructive diagenesis such as dissolusion,karstification,fracture diagenesis,pressolution led the protolith forming lots of secondary pores,and improved the reservoir capability accordingly.The dstructive diagenesis such as cementation,filling and silicification reduced the proto-pore and secondary pore.Hydrothermal fluids action as the coin had its two sides.Carbonate karst reservoir experienced penecontemporaneous diagenesis stage,shallow-buried diagenetic stage,epidiagenetic stage and burial diagenetic stage.Controlled by the Middle-Late Caledonian to the Early Hercynian tectonic events,the carbonate reservoir experienced periods of epidiagenetic karstification,and they made up of intermittent diagenesis system.Accordingly,pore evolution experienced four stages as follows：Proto-pore formed and reduced stage,fracture-cavity formed stage,fracture-cavity reduced and filled stage,fracture formed and burial dissolusion stage.Proto-pores and early solution pores were filled mostly,and they were invalid.The Middle-Late Caledonian to the Early Hercynian karstification were crucial for carbonate karst reservoir in the study area,preservation of the secondary pores,the fractures and the cavities formed by the karstification in the epidiagenetic stages and burial diagenesis stages are crucial for the formation of the high quality reservoir.
出处
《古地理学报》
CAS
CSCD
北大核心
2010年第4期467-479,共13页
Journal of Palaeogeography：Chinese Edition
基金
国家科技重大专项"大型油气田及煤层气开发"(编号:2008ZX05004-002)
中国石油塔里木油田分公司2008年度博士后项目(编号:041009080045)共同资助
