Comprehensive study on genetic pathways and parent materials of secondary biogenic gas in coalbeds  

作　　者：Mingxin Tao Wanchun Wang Zhongping Li Yuzhen Ma Jing Li Xiaobin Li 

机构地区：[1]State Key Laboratory of Earth Surface Processes and Resource Ecology/College of Resources Science and Technology, Beijing Normal University [2]Lanzhou Petroleum Resources Research Center, Institute of Geology and Geophysics, Chinese Academy of Sciences

出　　处：《Chinese Science Bulletin》2014年第10期992-1001,共10页

基　　金：supported by the National Natural Science Foundation of China(41172107);the National Basic Research Program of China(2002CB211701);the Program of State Key Laboratory of Earth Surface Processes and Resource Ecology(2011-zy-04)

摘　　要：The types of substances in coal rock used by microbes,the specific ways in which microbes produce secondary biogenic gas(SBG)and whether substances exist in the coal seam for the formation of a large amount of SBG are important basic scientific issues.This paper conducts a systematic and comprehensive research study on the above issues using methods such as the isotopic tracing of gas,the analysis of coal organic geochemistry,and gas-producing simulation experiments of coal.Results show that the formation of SBG is by the microbial reduction of CO2and the SBG-producing coal seam undergoes microbial degradation.The thermogenic heavy gaseous hydrocarbons have also been degraded by microorganisms and possibly transformed into microbialoriginated CO2.A large amount of CO2,a relatively large amount of H2and a certain amount of heavy gaseous hydrocarbons may form in the thermal evolution of coal.These substances and the microbial-originated CO2and coal seam water can finally become parent materials of SBG.These components are rich in coal seams of medium–low thermal evolution,which should be the main coal seams for SBG formation and exploration.The types of substances in coal rock used bymicrobes, the specific ways in which microbes produce sec-ondary biogenic gas （SBG） and whether substances exist inthe coal seam for the formation of a large amount of SBG areimportant basic scientific issues. This paper conducts a sys-tematic and comprehensive research study on the above issuesusing methods such as the isotopic tracing of gas, the analysisof coal organic geochemistry, and gas-producing simulationexperiments of coal. Results show that the formation of SBG isby the microbial reduction of CO2 and the SBG-producingcoal seam undergoes microbial degradation. The thermogenicheavy gaseous hydrocarbons have also been degraded bymicroorganisms and possibly transformed into microbial-originated CO2. A large amount of CO2, a relatively largeamount of H2 and a certain amount of heavy gaseous hydro-carbons may form in the thermal evolution of coal. Thesesubstances and the microbial-originated COz and coal seamwater can finally become parent materials of SBG. Thesecomponents are rich in coal seams of medium-low thermalevolution, which should be the main coal seams for SBGformation and exploration.

关 键 词：SECONDARY BIOGENIC GAS Geneticpathway PARENT materials ISOTOPIC TRACING Coalbed GAS 

分 类 号：P618.13[天文地球—矿床学]