海相油气地质2024，Vol.29Issue(4)：385-400,16.DOI:10.3969/j.issn.1672-9854.2024.04.005
川东北深层页岩储层成岩作用及对孔隙发育的影响
Diagenesis and its influence on pore development of deep shale reservoirs in northeastern Sichuan Basin:a case study of Wujiaping Formation and Dalong Formation in Well DY1H
摘要
Abstract
The marine shales of Wujiaping Formation and Dalong Formation in Sichuan Basin have favorable conditions for shale gas accumulation,making them significant replacement fields for natural gas exploration in the future.However,due to mixed sedimentation influences,diagenesis and pore evolution vary significantly among different lithofacies.The lithofacies classification,diagenesis,and microscopic pore structure of Wujiaping Formation and Dalong Formation shales of Well DY1H in northeast Sichuan Basin are confirmed by useing X-ray diffraction,scanning electron microscopy,energy spectrum analysis,and thin section observation techniques.We also discuss the coupling relationship between diagenesis and pore development.The results reveal that four types of shale lithofacies are predominantly present in well DY1H:siliceous,mixed,calcareous,and clay-rich shales.The siliceous shale has the highest TOC.Part of the quartz in the siliceous shale comes from the transformation of siliceous organisms in the early diagenesis.This early cementation enhances the compaction resistance of the reservoir,and the retained micropores can provide space for the migration and enrichment of organic matter.With the increase of burial depth,a large number of organic pores can be formed under the thermal evolution of organic matter.Due to their high-quality material foundation and favorable storage conditions,siliceous shales have become preferred lithofacies within the Wujiaping Formation and Dalong Formation shales in northeast Sichuan Basin.Finally,a diagenetic pore evolution model is established specifically for these favorable lithofacies which can serve as a reference for studying pore genesis and reservoir distribution prediction in marine shales.关键词
成岩作用/储层特征/孔隙成因/页岩气/吴家坪组/大隆组/川东北地区Key words
diagenesis/reservoir characteristics/pore genesis/shale gas/Wujiaping Formation/Dalong Formation/northeast Sichuan Basin分类
能源科技引用本文复制引用
杨雨然,何亮,徐亮,马维泽,杨雪,李润彤,朱逸青,王青,李彦佑,伍秋姿..川东北深层页岩储层成岩作用及对孔隙发育的影响[J].海相油气地质,2024,29(4):385-400,16.基金项目
本文受中国石油天然气集团有限公司科技项目"新区新层系有利区优选与勘探评价关键技术研究"(编号:2023ZZ21YJ04)、中国石油西南油气田公司科研项目"四川盆地北部二叠系海相页岩储层评价体系研究"(编号:2024D104-01-11)、中国石油西南油气田公司科研项目"川北地区二叠系海相优质页岩展布规律与储层主控因素研究"(编号:20230304-08)、中国石油天然气股份有限公司气藏评价项目"川东地区二叠系海相页岩有利建产目标优选"联合支助 （编号:2023ZZ21YJ04）
