Geological control of differential enrichment of deep coalbed methane in the Ordos Basin
范立勇周国晓杨兆彪王怀厂卢本举张宝鑫陈宇航李存磊王彦卿顾俊雨
FAN Liyong;ZHOU Guoxiao;YANG Zhaobiao;WANG Huaichang;LU Benju;ZHANG Baoxin;CHEN Yuhang;LI Cunlei;WANG Yanqing;GU Junyu
低渗透油气田勘探开发国家工程实验室中国石油长庆油田公司勘探开发研究院中国矿业大学 煤层气资源与成藏过程教育部重点实验室
鄂尔多斯盆地深部煤层气资源丰富,开发潜力大,是中国深部煤层气勘探开发的主战场。明确深部煤层气富集规律、圈定富集区段是煤层气勘探开发的重要基础。以中国石油长庆油田公司在鄂尔多斯盆地最新实施的多口深部煤层气评价井数据为分析基础,采用数学统计、模型计算和地质分析等方法,重点研究了盆地内深部煤层气差异富集的地质控制因素和富集规律。提出了物质组分效应、深度效应和保存效应是影响深部煤层气差异富集的“3种控制效应”。物质组分是控制煤层气富集的基础因素,其中灰分和煤变质程度是主要参数,低灰分、高变质煤储层含气量高。深度效应则是叠加孔隙度、温度和压力变化的综合效应,孔隙度随埋深增加而衰减,导致游离气随埋深增加会趋缓,吸附气和总含气量存在明显的临界转换深度,后者临界转换深度深于前者,一般在
The deep coalbed methane (CBM) resources in the Ordos Basin are abundant and have great development potential, making it the main battlefield for exploration and development of deep CBM in China. Among them, clarifying the enrichment law of deep CBM and delineating enrichment sections are important foundation for CBM exploration and development. Based on the analysis of data from a number of deep evaluation CBM wells recentlyimplemented by China petroleum Changqing Oilfield company in Ordos Basin, the geological control factors and enrichment rules of deep coalbed methane differential enrichment in the basin are studied by means of mathematical statistics, model calculation and geological analysis. It has been proposed that the effects of material composition, depth, and preservation are the "three controlling effects" that affect the differential enrichment of deep CBM.The material component is the main factor controlling the enrichment of CBM, among which ash yield and coal metamorphism degree are the main parameters, low ash content, high metamorphic coal with high gas content. The depth effect is a comprehensive effect of superimposed porosity, temperature, and pressure. The porosity decays with the increase of burial depth, resulting in the free gas will tend to slow down with the increase of burial depth, and the adsorbed gas exists obvious critical conversion depth, and the critical conversion depth of total CBM content is deeper than the critical conversion depth of adsorbed CBM, which is generally in the range of
深部煤层气物质组分效应深度效应保存效应富集模式鄂尔多斯盆地.
Deep CBM;Material compositioneffect;Depth effect;Preservation effect;Enrichment mode;Ordos Basin.
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会