川中高磨地区中二叠统栖霞组天然气成藏条件及过程  

Geological conditions and process of gas accumulation in Middle Permian Qixia Formation,Gaoshiti-Moxi area,central Sichuan Basin

作　　者：白晓亮 陈燕萍 彭思桥 王尉 李堃宇 王伟[2] 苏桂萍 BAI Xiaoliang;CHEN Yanping;PENG Siqiao;WANG Wei;LI Kunyu;WANG Wei;SU Guiping(Exploration and Development Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Si-chuan 610041,China;State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation,Chengdu Univer-sity of Technology,Chengdu,Sichuan 610059,China)

机构地区：[1]中国石油西南油气田公司勘探开发研究院,四川省成都市610041 [2]油气藏地质及开发工程国家重点实验室·成都理工大学

出　　处：《天然气勘探与开发》2023年第4期80-90,共11页Natural Gas Exploration and Development

摘　　要：川中高磨地区中二叠统栖霞组作为继寒武系产层之外重要的接力层系,近年来获得了较大的勘探突破。基于该区栖霞组岩心薄片观察、天然气地球化学分析、流体包裹体测温分析等,开展川中高磨地区栖霞组油气成藏地质条件研究,同时结合区域埋藏—热演化史恢复结果,明确栖霞组成藏主控因素,揭示栖霞组油气成藏演化过程。研究结果表明,川中高磨地区栖霞组成藏条件较好,具体表现为:①栖霞组白云岩储层孔、洞、缝发育,纵向上呈薄层多期叠置的特征;②天然气以下寒武统优质烃源岩供烃为主,伴有部分中二叠统烃源岩,志留系龙马溪组烃源岩在研究区南部有一定的贡献,为油气藏形成提供物质基础;③东西向走滑断裂为天然气垂向输导提供有利通道,建立源储联系,利于富集成藏;④高磨地区栖霞组气藏现今表现为构造背景下的岩性气藏,气藏的形成经历了印支期古油藏→燕山期古气藏→现今气藏的演化过程,研究区在整个过程中没有较大的调整改造,表现为原位富集,高效成藏的特点。The exploration for the Middle Permian Qixia Formation,an important successor to the Cambrian producing formations,has made great breakthroughs in recent years in the Gaoshiti-Moxi area of central Sichuan Basin.Based on core thin-section observation,natural gas geochemical analysis,and fluid inclusion thermometric analysis,the geological conditions for hydrocarbon accumulation in the Formation were discussed.Meanwhile,coupling with the restoration of regional burial-thermal evolution history,the main factors controlling the hy-drocarbon accumulation were identified,and the reservoir evolution process was revealed.The results indicate that the Qixia Formation has good geological conditions for hydrocarbon accumulation.(i)the Qixia Formation dolomite reservoirs contain pores,vugs and fractures,with multi-stage superimposed thin layers vertically.(ii)Natural gas is mainly supplied by the high-quality source rocks of the Lower Cam-brian,partially by some source rocks of the Middle Permian,and by certain source rocks of the Silurian Longmaxi Formation(mainly in the southern part of the study area).(iii)The E-W strike-slip faults serve as favorable pathways for the vertical migration of natural gas,commu-nicating the source rocks and reservoir rocks to favor the gas accumulation.(iv)The gas reservoirs of the Qixia Formation are currently lith-ologic reservoirs under the tectonic setting.These reservoirs have undergone an evolution process from the Indosinian oil paleo-reservoir to the Yanshan gas paleo-reservoir and then to the present gas reservoir.In this process,the study area did not suffer remarkable adjustment and transformation,and reflects in-situ enrichment and efficient accumulation of gas.

关 键 词：川中高磨地区 油气成藏条件 成藏过程 中二叠世 栖霞组 油气充注期次 

分 类 号：P618.13[天文地球—矿床学]