岩石矿物学杂志2024，Vol.43Issue(1)：63-73,11.DOI:10.20086/j.cnki.yskw.2024.0105
致密砂岩气藏地层水水化学特征及其地质意义
Hydrochemical characteristics of formation water in tight sandstone gas reservoirs and their geological significance:A case study of the Xinchang Gas Field in Western Sichuan Depression
摘要
Abstract
The Jurassic Shaximiao Formation and Triassic Xujiahe Formation in the Sichuan Basin serve as key replacement areas for increased storage and production of onshore tight gas resources.They possess substantial reserves that are challenging to exploit and hold significant exploration and development potential.However,exten-sive and ongoing exploratory drilling and development have led to significant water production from wells in both the shallow Shaximiao Formation and the deeper Xujiahe Formation gas reservoirs.This water production has severely constrained the gas production capacity of these wells,with some wells even ceasing production due to water flooding.This study conducted an analysis of the formation water from 34 gas wells at various stratigraphic levels in the study area,focusing on major and trace elements,as well as the evolutionary characteristics of the reservoirs.The results indicate that both the Shaximiao Formation and the Xujiahe Formation gas reservoirs underwent an evolutionary process of initial formation,subsequent compaction,and subsequent modification.Fault connectivity resulted in significant upwelling of formation water from the deep Xujiahe Formation,leading to substantial infiltration into highly permeable sand bodies adjacent to faults.Under the influence of hydrodynamics and other driving forces,natural gas efficiently migrated vertically along fault zones in either a free or dissolved phase.Vertically,the major-ity of ion concentrations increased progressively with depth.The deep Xujiahe Formation gas reservoirs exhibit favorable conditions for oil and gas preservation and have undergone more complex water-rock interactions,causing varying degrees of enrichment in elements such as K,Ba,Sr,Li,and Rb.关键词
新场气田/致密砂岩/沙溪庙组/须家河组/地层水/水化学Key words
Xinchang Gas Field/tight sandstone/Shaximiao Formation/Xujiahe Formation/formation water/hydrochemistry分类
地质学引用本文复制引用
山俊杰,黄仕林,毕有益,邓美洲,严焕榕,衡勇,郑艳..致密砂岩气藏地层水水化学特征及其地质意义[J].岩石矿物学杂志,2024,43(1):63-73,11.基金项目
中国石化科技部项目(P21040)Sinopec Science and Technology Department Project(P21040) （P21040）
