柴北缘九龙山地区侏罗系成岩作用特征  

Diagenesis Characteristics of Jurassic in Jiulongshan Area,Northern Qaidam Basin

作　　者：王猛 耿榕悦 马富强[3] 孙国强 蒋赟 潘世乐 WANG Meng;GENG Rong-yue;MA Fu-qiang;SUN Guo-qiang;JIANG Yun;PAN Shi-le(Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China;University of Chinese Academy of Sciences, Beijing 100049, China;Research Institute of Exploration and Development, PetroChina Qinghai Oilfield Company, Dunhuang 736202, China)

机构地区：[1]中国科学院西北生态环境资源研究院,兰州730000 [2]中国科学院大学,北京100049 [3]中国石油青海油田公司勘探开发研究院,敦煌736202

出　　处：《科学技术与工程》2021年第15期6175-6184,共10页Science Technology and Engineering

基　　金：中国科学院“西部之光”人才培养计划(Y304RC1SGQ);甘肃省自然科学基金(1308RJZA310);甘肃省重点实验室专项(1309RTSA041)。

摘　　要：生产实践表明九龙山地区侏罗系地层油源丰富,但对储层研究至关重要的成岩作用方面的研究却较为笼统,制约了该区进一步地勘探开发。通过对九龙山地区重点探井岩芯样品的观测、岩石薄片的鉴定和扫描电镜照片的观察辨别,结合相关地球化学资料,系统地研究了柴北缘九龙山地区侏罗系碎屑岩储层的岩石学特征、成岩作用特征,对成岩阶段进行了划分;结果表明:①研究区侏罗系储集岩岩石类型主要为灰色中-粗粒岩屑砂岩,储集砂岩粒度较粗,以中砂、粗砂和细砂岩为主;②成岩作用类型主要为压实作用、胶结作用以及溶蚀作用。研究区储集层经历了较强机械压实作用改造,使得原生孔隙度降低;以碳酸盐胶结为代表的胶结作用,较大程度地破坏了储层物性;碳酸盐类胶结物的溶蚀产生了大量次生孔隙,提高了储层的有效孔隙度;③研究区成岩作用较强,成岩演化主要处于中成岩阶段A期。Production practice shows that the Jurassic strata in Jiulongshan area is rich in oil sources,but the research on diagenesis,which is crucial for reservoir research,is relatively general,which restricts further exploration and development in this area.Based on the observation of core exploration core samples in Jiulongshan area,the identification of rock flakes,the observation of scanning electron micrographs and the related geochemical data,the petrological and diagenetic characteristics of the Jurassic clastic reservoirs in the Jiulongshan area of the northern margin of the Qaidam Basin was systematically studied,and the diagenetic stages were divided.The results show as follows.The rock types of the Jurassic reservoir rocks in the study area are mainly gray medium-coarse lithic sandstones,and the sandstones of the reservoir sandstones are coarse,mainly composed of medium sand,coarse sand and fine sandstone.The types of diagenesis are mainly compaction,cementation and dissolution.The reservoir in the study area has undergone a strong mechanical compaction modification,which reduces the primary porosity;the cementation represented by carbonate cementation largely destroys the reservoir physical properties;the dissolution of carbonate cements produces a large number of secondary pores,which increases the effective porosity of the reservoir.The diagenesis of the study area is strong,and the diagenetic evolution is mainly in the phase A of the mesodiagenetic stage.

关 键 词：成岩作用 成岩阶段划分 侏罗系 九龙山地区 

分 类 号：P588[天文地球—岩石学]