羌塘盆地昂达尔错古油藏油气来源及成藏模式  

Hydrocarbon Source and Reservoir Forming Model for the Paleo-reservoir of Angdarco Area in Qiangtang Basin

作　　者：彭清华[1] 杜佰伟[2] 谢尚克[2] PENG Qing-hua;DU Bai-wei;XIE Shang-ke(Research Center of Applied Geology,China Geological Survey,Chengdu 610036,China;Chengdu Center of China Geological Survey,Chengdu 610081,China)

机构地区：[1]中国地质调查局应用地质研究中心,成都610036 [2]中国地质调查局成都地质调查中心,成都610081

出　　处：《科学技术与工程》2022年第33期14599-14607,共9页Science Technology and Engineering

基　　金：中国地质调查局“西藏羌南-措勤地区油气地质调查”二级项目(DD20190116)。

摘　　要：昂达尔错油砂带是羌塘盆地内规模最大的古油藏,明确其油气来源和成藏模式对指导该地区的油气资源勘探具有重要意义。以饱和烃色谱-质谱、单体烃碳同位素和流体包裹体分析为基础,对羌塘盆地昂达尔错古油藏油气来源、成藏期次及成藏模式进行了探讨。研究表明:昂达尔错古油藏油苗与下侏罗统曲色组烃源岩具有相似的生物标志化合物组合特征,体现出两者具有较强的亲缘性;昂达尔错古油藏油气充注期次可划分为晚侏罗世(151.6~158.7 Ma)、早白垩世(142.3~143.9 Ma)与中新世(12.5~16.6 Ma)三期,其中早白垩世为该古油藏的主充注期;古油藏油源为下侏罗统曲色组页岩,储集层为中侏罗统布曲组砂屑灰岩和白云岩,盖层为布曲组泥晶灰岩,构成正常的“下生上储”式成藏组合。The Angdarco oil sand belt is the largest paleo-reservoir in Qiangtang Basin.It is of great significance to clarify its oil and gas source and reservoir forming model for guiding the oil and gas resource exploration in the area.Based on analysis of saturated hydrocarbons chromatogram-mass spectrometry,individual hydrocarbon isotopic and fluid inclusion,the oil sources,pool-forming stages and reservoir forming model of Angdarco paleo-reservoir were discussed.The research shows that oil seepages of Angdarco paleo-reservoir and source rocks of lower Jurassic Quse Formation have similar characteristics of biomarker combination,indicating that they have close genetic relationship.There are three stages of oil-gas accumulation in Angdarco paleo-reservoir,which occured in the Late Jurassic(151.6~158.7 Ma),early Cretaceous(142.3~143.9 Ma)and Miocene(12.5~16.6 Ma),and its main accumulation period is in early Cretaceous stage.The source rock of Angdarco paleo-reservoir is shale of lower Jurassic Quse Formation,reservoir was sandstone and dolomite of Buqu Formation,and the cap was micrite of the Buqu Formation,which forms a normal reservoir-forming combination of“lower generation and upper storage”.

关 键 词：古油藏 油气来源 成藏模式 昂达尔错地区 羌塘盆地 

分 类 号：P618[天文地球—矿床学]