摘要
准南煤田乌鲁木齐河东矿区是新疆在煤层气多年勘查过程中发现的地质资源较好区块,但在参数井煤层气成分分析结果表明41#、42-43#、45#煤层煤层气成分中的二氧化碳浓度普遍偏高,从河东矿区构造地质背景入手,重点针对该区存在的火烧区,结合水文地质特征,分析煤层气中CO_(2)高异常的成因,分析煤层地下自燃对煤层气成分的影响以及各成分之间的关系,并且从向斜成藏角度解释了深部受火烧影响煤层CO_(2)含量较高,而其他未受火烧影响的煤层CO_(2)含量正常。研究发现河东矿区煤层中CO_(2)的主要来自受火烧区煤层自燃及围岩受火烧高温炙烤产生和次生生物气的形成过程中产生2个方面。受到八道湾向斜构造的影响,煤层气及成分中的CO_(2)在河东矿区形成典型的向斜成藏富集模式,即CO_(2)通过从地表向下渗流的地下水,不断向轴部运移,位于轴部的储层压力升高,形成超压滞留水区,因而CO_(2)在深部得以富集,形成高异常。
The Urumqi Hedong mining area of the Zhunnan coalfield is a block with good geological resources discovered in the process of coalbed methane exploration for many years in Xinjiang.However,the analysis results of the coalbed methane composition in the parameter well show that the coalbed methane composition of No.41,No.42-43 and No.45.The concentration of carbon dioxide is generally high.Started from the tectonic geological background of the Hedong mining area,focusing on the fire areas in the area,combined with hydrogeological characteristics,and analyzed the causes of abnormal high CO_(2) in coalbed methane,and analyzed the influence of underground spontaneous combustion on the composition of coalbed methane.The relationship between the components,and from the perspective of syncline accumulation,explains that the CO_(2) content of deep coal seams affected by fire is higher,while the CO_(2) content of other coal seams not affected by fire is normal.The study found that the CO_(2) in coal seams in Hedong mining area mainly comes from the spontaneous combustion of coal seams in the burned area,the production of surrounding rocks by high-temperature scorching and the formation of secondary biogas.Affected by the Badaowan syncline structure,the CO_(2) in coalbed methane and its constituents forms a typical syncline accumulation and enrichment pattern in the Hedong mining area,that is CO_(2) continuously migrates to the axis through groundwater seepage from the surface downwards,located in the axis the reservoir pressure in the lower part rises,forming an overpressure retention water zone,so CO_(2) is enriched in the deep part,forming a high anomaly.
作者
来鹏
杨曙光
张娜
杜世涛
LAI Peng;YANG Shuguang;ZHANG Na;DU Shitao(CBM R&D Center,Xinjiang Coal Geological Bureau,Urumqi 830091,China;No.161 Coal Exploration Team,Xinjiang Coal Geological Bureau,Urumqi 830046,China)
出处
《煤炭技术》
CAS
北大核心
2023年第11期118-123,共6页
Coal Technology
基金
新疆维吾尔自治区自然科学基金资助项目(2020D01A97)。
关键词
河东矿区
煤层气
二氧化碳
成因分析
Hedong mining area
coalbed methane
carbon dioxide
cause analysis
