鄂尔多斯盆地南部旬-宜探区深部煤层气成藏条件与勘探潜力

Reservoir-forming conditions and exploration potential of deep coalbed methane in Xun-Yi exploration area,southern Ordos Basin

在充分调研国内深部煤层气勘探研究成果的基础上,依据鄂尔多斯盆地南部旬-宜探区钻井、地震和煤心实验分析资料,分析深部石炭系太原组煤层分布、煤岩煤质、储层条件、保存条件及含气性等关键成藏要素,系统评价了旬-宜探区太原组煤层气成藏条件与勘探潜力。结果表明,旬-宜探区太原组煤层厚度大、横向分布稳定、煤阶高、灰分中等、含气性较好,具备良好的煤层气成藏条件;太原组煤层气资源量1754×10^(8) m^(3),具备良好的勘探潜力;旬-宜探区中东部煤层发育、含气量高、断裂不发育、煤层埋深相对较浅,为煤层气勘探有利区带;在有利区优选基础上,开展了煤层气老井复查,优选了PZ2井实施太原组煤层压裂试气,压后取得了较好效果,对该区下一步煤层气勘探具有参考意义。

Based on the research results of deep coalbed methane exploration in China,and the analysis data of drilling,seismic and coal core experiments in the Xung-Yi exploration area in the southern Ordos Basin,the key factors of deep Carboniferous Taiyuan Formation,such as coal seam distribution,coal rock and coal quality,reservoir conditions,preservation conditions and gas bearing properties are analyzed,and then the reservoir-forming conditions and exploration potential of coalbed methane in Taiyuan Formation are evaluated.The results show that the coal seam of Taiyuan Formation in the Xen-Yi exploration area has the advantages of large thickness,stable transverse distribution,high coal rank,medium ash content and good gas bearing.The coal bed methane resources of Taiyuan Formation are 1754×10^(8) m^(3),which has a good exploration potential.The coal seam is developed in the middle and eastern part of the Xun-Yi exploration area,with high gas content,undeveloped faults and relatively shallow buried depth,which is a favorable area for coalbed methane exploration.On the basis of the selection of favorable areas,the review of old coalbed methane wells has been carried out,and the PZ2 well has been selected to carry out the gas test of Taiyuan Formation coal seam by fracturing,which has a good reference for further exploration in this area.