影响泥岩盖层质量的主要因素及评价新思路  

The main factors affecting the quality of mudstone caprock and a new idea for its evaluation

作　　者：娄敏 杨香华[2] 尤丽 代龙 王宁 邱凌越 LOU Min;YANG Xianghua;YOU Li;DAI Long;WANG Ning;QIU Lingyue(Shanghai Branch of CNOOC Ltd.,Shanghai 200335,China;Faculty of Earth Resources,China University of Geosciences,Wuhan 430074,China;Zhanjiang Branch of CNOOC Ltd.,Zhanjiang 524057,China;China University of Petroleum,Beijing 102249,China)

机构地区：[1]中海石油(中国)有限公司上海分公司,上海200335 [2]中国地质大学资源学院,武汉430074 [3]中海石油(中国)有限公司湛江分公司,广东湛江524057 [4]中国石油大学,北京102249

出　　处：《成都理工大学学报（自然科学版）》2021年第1期82-93,共12页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家科技重大专项(2016ZX05024-006)。

摘　　要：利用突破压力、盖层物性、排驱压力、扩散系数、中值压力等实验室定量参数,结合泥岩微观组构、岩矿组成、伊利石结晶度等沉积成岩定性参数,综合评价莺歌海盆地东方区和乐东区泥岩盖层的封闭性。结果表明,不同质量泥岩盖层的沉积成岩特征存在差异。质量好的泥岩盖层岩性为黏土粉砂质泥岩,黏土含量较高,碳酸盐含量中等,长石和石英含量较低,伊利石结晶度较低,岩石较致密,微孔发育,大孔和中孔不发育,裂缝多被充填,受重力流和牵引流影响较小,均质性较好。从沉积和成岩角度,为泥岩盖层评价提供了一种新思路,有效解决了单纯依靠突破压力、扩散系数等测试资料评价盖层时因样品受人工影响带来的不确定性。Based on laboratory quantitative parameters,such as breakthrough pressure,physical property of caprock,displacement pressure,diffusion coefficient and median pressure,combined with sedimentary diagenesis qualitative parameters,such as mudstone microstructure,rock composition and illite crystallinity,the sealing property of mudstone caprock in Dongfang-Ledong area of Yinggehai Basin was comprehensively evaluated.It shows that the sedimentary diagenetic characteristics of mudstone cover of different quality are different.The lithology of the mudstone caprock with good quality is composed of relatively compacted clay silty mudstone with high clay content,medium carbonate content,low feldspar and quartz content,low crystallinity of illite.Micro-pores,macro-pores and meso-pores were poorly developed and most cracks were filled in the mudstone.The mudstone caprock was less affected by gravity flow and traction flow with good homogeneity.From the perspective of deposition and diagenesis,a new way of thinking for the evaluation of mudstone caprock is proposed,which effectively solved the uncertainty caused by artificial influence of samples in the evaluation of mudstone caprock based only on test data,such as breakthrough pressure and diffusion coefficient.

关 键 词：盖层评价 微观结构 沉积特征 伊利石结晶度 

分 类 号：TE122.25[石油与天然气工程—油气勘探]