济阳坳陷孤北潜山煤成气成藏过程分析  

Analysis of Accumulation Process of Coal-Formed Gas in Gubei Buried Hill of Jiyang Depression

作　　者：张善文[1] 张林晔[2] 李政[2] 

机构地区：[1]中国石化胜利油田分公司,山东东营257001 [2]胜利油田地质科学研究院,山东东营257015

出　　处：《天然气地球科学》2009年第5期670-677,共8页Natural Gas Geoscience

基　　金：国家科技重大专项"渤海湾盆地南部精细勘探关键技术"(编号:2008zx05006-003)资助

摘　　要：根据气体组分、甲烷同系物碳同位素及轻烃参数,确定济阳坳陷孤北潜山带煤成气源主要为石炭—二叠系煤系烃源岩,中生界煤系烃源岩也具有一定的贡献,煤成气主要分布于第二排山、第三排山北部远离孤北断层地区及第四排山。在煤成气源确认的基础上,通过储集层流体包裹体均一温度及生烃动力学分析,结合烃源岩的生烃—埋藏史,认为该区石炭—二叠系煤系烃源岩经历了4次生烃过程,燕山期和喜马拉雅期是主要生烃期,中生界煤系烃源岩生烃期主要为喜马拉雅后期。该区煤成气藏可能有2种成因,一是源自石炭—二叠系煤系烃源岩的原生气藏在喜马拉雅期被破坏后再次聚集而成;二是喜马拉雅期埋藏较深的石炭—二叠系及中生界煤系烃源岩再次生烃形成,其中第二种成因的煤成气是今后孤北潜山带天然气勘探的重点。According to the compositions, carbon homolog isotope and light hydrocarbon parameters of natural gas in the Gubei buried-hill of Jiyang depression, we conclude that the coal-formed gases are mainly from Carboniferous-Permian coal measures as the source rock, and the Mesozoic coal measures do some part of contribution. Furthermore, the coal-formed gases are mainly preserved in the fourth row of buriedhills, as well as the north of second and third rows of buried-hills which are far away from the Gubei-fault. After identification of the coal-formed gases＇ source, homogenization temperature of the fluid inclusion, as well as hydrocarbon generation kinetics, history of hydrocarbon generation and sedimentation of the source rocks, the conclusion is that there are four periods in hydrocarbon generation of Carboniferous-Permian source rocks, among which the Yanshan period and Xishan period are the main periods, and the late Xisban period is the main period for the Mesozoic hydrocarbon source rocks. Also, there are two types of coal-formed gas pools in this area, one is the secondary gas pool formed after the primary pool of Carboniferous-Permian system, which is destroyed during the Xishan period, the other is that after the secondary hydrocarbon generation of the deep Carboniferous-Permian and Mesozoic coal measure source rocks in the later Tertiary period, among which the second type will be favorable in the natural gas exploration in this area.

关 键 词：孤北潜山 煤成气 碳同位素 生烃-埋藏史 成藏过程 

分 类 号：TE122.3[石油与天然气工程—油气勘探]