澳洲Bowen-Surat盆地煤层气富集规律及主控因素

Coal bed methane enrichment regularities and controlling factors in Bowen-Surat basin, Australia

澳大利亚是世界第四大煤炭生产国和世界上最大的煤炭输出国。2000年后,澳大利亚煤层气产业快速发展。Bowen-Surat盆地是澳大利亚最大的煤层气盆地。应用石油地质综合分析方法,总结了Bowen-Surat盆地的石油地质特征,进而分析了该盆地煤层气富集规律:平面上,煤层气富集在Taroom槽和Chinchilla-Goondiwindi斜坡中;剖面上,煤层气富集在二叠系Blackwater群和侏罗系Walloon组煤层中。针对煤层气藏在平面和剖面上的分布特点,结合沉积体系、气源岩、煤阶、孔隙度和渗透率等因素进行相关性分析,认为有8个因素主要控制了煤层气藏的分布,即:沉积控类型,气源控范围,煤阶、埋深和孔渗控含量,构造封闭控层位。

Bowen-Surat Basin is a superimposed rifting basin located in the eastern Australian and the largest CBMbasins in Australia. The paper, through a comprehensive analysis of petroleum geology methods, summarizesBowen-Surat basin petroleum geology characteristics, and then analyzes CBM enrichment regularities. In the planeCBM is enriched in the Taroom trough and Chinchilla-Goondiwindi slopes, vertically enriched in PermianBlackwater Group and Jurassic Walloon coal measures. Aiming at the planar and vertical distribution regularitiesof CBM reservoirs, combining with sedimentary system, gas source rock, coal rank, porosity, permeability andother factors and making the correlation analysis, the paper concluded that there are eight main factors controllingthe distribution of CBM reservoirs, i.e., sedimentary control, distribution range controlled by gas source rock, coalrank, depth, porosity and permeability, horizon controlled by structure confining.