摘要
煤微相与煤储层含气性密切相关,并决定煤的沉积环境和沉积物源,直接影响煤储层的生气潜力和赋存环境。从煤层厚度、煤岩物质组成和灰分产率3方面分析煤微相对煤储层含气性的控制作用,基于测井资料定量划分煤微相,进而预测煤储层产气前景。研究区3#煤层发育潮湿森林滞留沼泽相、干燥森林沼泽相、覆水森林活水沼泽相、湿地草本活水沼泽相和干燥草本沼泽相5种煤微相。潮湿森林滞留沼泽相、干燥森林沼泽相及覆水森林活水沼泽相煤储层有效厚度较大;覆水森林活水沼泽相物性相对较好;潮湿森林滞留沼泽相和湿地草本活水沼泽相灰分含量及夹矸相对较少。潮湿森林滞留沼泽相生气潜力强,干燥森林沼泽相、覆水森林活水沼泽相和湿地草本活水沼泽相生气潜力中等,干燥草本沼泽相生气潜力较弱。利用密度、自然伽马和自然电位等测井曲线可有效划分煤层有效厚度和夹矸厚度及灰分含量等特征参数,依据统计规律可匹配到对应的煤微相,进而有效评价煤储层含气性。
Coal microfacies are closely related to the gas-bearing properties of coal reservoirs,which determines the sedi-mentary environment and sedimentary source of coal and directly affects the potential of coalbed methane generation and the occurrence environment.The control effect of coal microfacies on coal reservoir gas-bearing properties was analyzed comprehensively from three aspects:coal seam thickness,coal reservoir physical property and ash yield.The coal microfa-cies was quantitatively divided to predict the gas production prospect of coal reservoir based on the logging data.In the study area,there are5kinds of coal microfacies in3#coal seam,such as moist forest detained swamp facies,dry forest swamp facies,water-overlying forest living swamp facies,wet herbaceous living marsh facies and dry herbaceous marsh fa-cies.The effective coal reservoir is thicker in moist forest detained swamp facies,dry forest swamp facies and water-cover-ing forest living swamp facies.The physical property of water-overlying forest living swamp facies is relatively good.There are a little ash and gangue in moist forest detained swamp facies and wet herbaceous living marsh facies.The potential of gas generation in moist forest detained swamp facies is great,it is moderate in dry forest swamp facies,water-covering for-est living swamp facies and wet herbaceous living marsh facies,and it is poor in dry herbaceous marsh facies.Density,natu-ral gamma and natural potential logging curves can be used effectively to divide the effective thickness of coal seam,the thickness of gangue and characteristic parameters such as ash content,which can be matched to the corresponding coal mi-crofacies according to the statistical law so as to effectively evaluate the gas-bearing property of coal reservoirs.
作者
敖旋峰
刘迪仁
徐观佑
郑佳佳
许巍
倪小威
AO Xuanfeng;LIU Diren;XU Guanyou;ZHENG Jiajia;XU Wei;NI Xiaowei(Key Laboratory of Exploration Technologies for Oil and Gas Resources,Ministry of Education,Yangtze University,Wuhan City,Hubei Province,430100,China;College of Geophysics and Petroleum Resources,Yangtze University,Wuhan City,Hubei Province,430100,China;Wuhan Xinye Human Resources Service Co.,Ltd.,Wuhan City,Hubei Province,430061,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2018年第3期55-60,共6页
Petroleum Geology and Recovery Efficiency
基金
国家自然科学基金项目"地层条件下富有机质页岩电磁响应机理与应用基础研究"(U1562109)
关键词
煤微相
含气性
储层评价
测井
沁水盆地
coal microfacies
gas-bearing property
reservoir evaluation
logging
Qinshui Basin
