喀什凹陷北缘阿克莫木气田气源探讨  

The Discussion on Natural Gas Source in Akmomu Gasfield,Northern Margin of Kashi Sag

作　　者：刘伟[1,2] 杨飞[3] 吴金才[4] 肖杭州 

机构地区：[1]中国矿业大学,江苏徐州221116 [2]煤层气资源与成藏过程教育部重点实验室,江苏徐州221116 [3]长江大学,湖北武汉430100 [4]吉斯克能源技术有限公司,北京100012 [5]吉林油田乾安采油场,吉林松原131400

出　　处：《天然气地球科学》2015年第3期486-494,共9页Natural Gas Geoscience

摘　　要：喀什凹陷北缘的阿克莫木气田天然气来源一直存在争议。喀什凹陷北缘地区石炭系新发现剖面有机质丰度低,生烃潜力有限。而喀什凹陷中心虽然有机质丰度高,但与阿克莫木气田之间有数条断层和断块阻隔。流体包裹体与断裂活动时间分析表明天然气充注在逆冲断层形成之后,故石炭系天然气很难运移至阿克莫木气田。二叠系有机质丰度中等,在乌恰构造带北部埋深加大,烃源岩的热演化程度显著增加,具备生成高成熟度干气的潜力。热压模拟实验结果表明,阿克1井天然气碳同位素特征与二叠系和侏罗系康苏组烃源岩500℃模拟气比较接近。综合阿克1井天然气地球化学特征、热模拟实验结果及油气充注时间和运移条件的匹配关系,认为阿克莫木气田天然气可能主要来自乌恰构造带北部的二叠系烃源岩和侏罗系康苏组烃源岩。The gas source of Akmomu Gasfield is still controversial. Based on the research of three main sets of source rocks in Kashi Sag,extra-low organic matter abundance in Carboniferous of the northern margin of Kashi Sag was found and it indicates that hydrocarbon-generating potential of Carboniferous is low. Ac cording to the matching relation between gas filling time and hydrocarbon migration conditions, the migration of hydrocarbon from the center of Kashi Sag to Akmomu Gasfield is impossible. So natural gas of Ak momu gasfield cannot be generated by Carboniferous. The organic matter abundance of Permian is medium in this area, which is better than once thought. As burial depth of Permian increases toward north in the north of well Ake 1,the maturity of Permian increased significantly which make it possible for Permian to generate dry gas with high maturity. The results of hot-pressing simulation experiment show that the carbon isotope characteristics of natural gas from well Ake 1 are similar to that of simulating gas of Permian and Jurassic Kangsu Formation, at 500℃. Combined with the geochemical characteristics of natural gas from well Ake 1,the matching relationship between gas filling time and hydrocarbon migration conditions and analysis of the experimental results of thermal simulation,it is concluded that the natural gas of Akmomu Gasfield may come from the source rocks of Permian and Jurassic Kangsu Formation.

关 键 词：喀什凹陷 模拟气 运移 碳同位素 气源 

分 类 号：TE122.1[石油与天然气工程—油气勘探]