乡宁矿区聚煤规律及控气作用研究

Study on coal accumulation law and gas control effect in Xiangning mining area

乡宁矿区位于鄂尔多斯盆地东缘的河东煤田南部,建设绿色矿山,开发煤层气绿色能源,需要对聚煤规律及控气作用进行研究。本文以乡宁矿区含煤地层石炭系-二叠系的聚煤规律及其控气作用为研究对象,通过对该区的钻探资料、煤层气试井资料、化验测试资料、岩心资料、镜下观察鉴定等成果资料进行分析,研究了该区含煤地层的沉积环境、聚煤规律、储集层物性特征、烃源岩特征、煤储层含气性等内容。研究结果认为,该区主要可采煤层发育稳定,厚度较大,2号主采煤层形成于浅水三角洲分流涧湾地带,煤层聚积期相对稳定,成煤物质充分,堆积与补偿均衡,泥炭沼泽发育,10号主采煤层是在潟湖、潮坪长期拓展夷平沼泽化后开始形成,气候适宜,植物繁茂,成煤物质丰富,沉积补偿作用均衡。2号煤层平均埋深750 m,10煤层平均埋深810 m,埋深适中,开展聚煤规律及控气研究可为该区煤炭及煤层气勘探开发提供理论指导。

Xiangning mining area is located in the southern part of Hedong coalfield in the eastern margin of Ordos Basin.In order to build a green mine and develop coalbed methane green energy,it is necessary to study the law of coal accumulation and gas control.In this paper,the coal accumulation law and gas control effect of Carboniferous-Permian coal-bearing strata in Xiangning mining area were taken as the research object.Through the analysis of drilling data,coalbed methane well test data,laboratory test data,core data,microscopic observation and identification results in this area,the sedimentary environment,coal accumulation law,reservoir physical characteristics,source rock characteristics and gas content of coal-bearing strata in this area were studied.The results showed that the main mineable coal seams in this area were stable and thick.The No.2 main coal seam was formed in the shallow water delta diversion bay area.The coal seam accumulation period was relatively stable,the coal-forming material was sufficient,the accumulation and compensation were balanced,and the peat swamp was developed.The No.10 main coal seam was formed after the long-term expansion of the lagoon and tidal flat.The climate was suitable,the plants were lush,the coal-forming materials were rich,and the sedimentary compensation was balanced.The average buried depth of No.2 coal seam was 750 m,and the average buried depth of No.10 coal seam was 810 m.The buried depth was moderate.The research on coal accumulation law and gas control could provide theoretical guidance for the exploration and development of coal and coalbed methane in this area.