塔里木盆地塔东地区震旦系—下古生界碳酸盐岩油气生储条件与勘探领域  

A study of source rocks & carbonate reservoirs and its implication on exploration plays from Sinian to Lower Paleozoic in the east of Tarim Basin,northwest China

作　　者：沈安江 付小东 张友 郑兴平 刘伟[3] 邵冠铭 曹彦清[4] 

机构地区：[1]中国石油杭州地质研究院,浙江杭州310023 [2]中国石油集团碳酸盐岩储层重点实验室,浙江杭州310023 [3]中国石油勘探开发研究院,北京100083 [4]中国石油大庆油田分公司勘探开发研究院,黑龙江大庆163712

出　　处：《天然气地球科学》2018年第1期1-16,共16页Natural Gas Geoscience

基　　金：国家科技重大专项"寒武系-中新元古界碳酸盐岩规模储层形成与分布研究"(编号:2016ZX05004-002)资助

摘　　要：塔里木盆地塔东地区震旦系—下古生界碳酸盐岩历经27年的勘探,多口探井见工业油气流或良好油气显示,但至今没有形成规模储量和产量,烃源岩生烃史、资源量和规模储层分布不清是关键制约因素。通过大量的露头、岩心和薄片、单井和地球化学测试资料分析,取得了4个方面的新认识:(1)在前人认为的塔东发育中下寒武统、中下奥陶统2套烃源岩的基础上,新增震旦系、上奥陶统2套烃源岩;(2)对埋藏史的重新认识改变了前人认为的烃源岩快速埋藏和高—过成熟导致生烃时窗短、生烃量有限的观点,指出晚奥陶世至二叠纪末长期处于生油窗范围,4套烃源岩有充足的时间大量生成液态烃,可使油气资源量显著增加;(3)在前人的印支—燕山期原油裂解气认识基础上,指出喜马拉雅期的快速深埋可使源内和源外滞留分散液态烃"接力"生气,新增资源量超过预期;(4)指出塔东震旦系—下古生界发育5类储层,相控性明显,有规模可预测。基于新的认识落实塔东地区震旦系—下古生界碳酸盐岩天然气资源量(1.33~1.66)×10^(12)m^3,推动了对塔东隆起和古城低凸起2个现实勘探领域以及3个潜在勘探领域的评价。With 27 years exploration of Sinian to Lower Paleozoic carbonate rocks in eastern Tarim Basin,hydrocarbon shows and some industrial oil and gas wells have been discovered there.However,so far no scale reserves and production have been obtained.Hydrocarbon generation,distribution of scaled resourcesreservoirs are the key constraints.In this paper,with observation of outcrops,cores,thin sections,and analyses of well-log,geochemical test data,four new understandings have been put forward.Firstly,on the basis of previous thoughts that there are two sets of source rocks,Middle-Lower Cambrian and Middle-Lower Ordovician source rock,another two sets of source rocks,Sinian and Upper Ordovician source rocks,have been newly discovered.Secondly,the new understanding of burial history changed the previous view that rapid burial of source rocks and high-over maturity lead to short time hydrocarbon generation window and limited hydrocarbon amount.It＇s thought that the source rocks maintained in the oil window for a long-term from Late Ordovician to the Late Permian.And four sets of source rocks have plenty time to generate much liquid hydrocarbon.Thirdly,guided by the former thought of oil cracked gas in Indosinian and Yanshan epochs,it＇s believed that rapid deep burial in Himalayan might cause stranded and dispersed liquid hydrocarbon in source rocks to relay hydrocarbon.Fourthly,five types of Sinian to Lower Paleozoic reservoirs are recognized in eastern Tarim Basin.They are all dominated by sedimentary facies and scaled reservoirs would be predictable.These understandings made（1.92-2.01）×10^（12） m^3 gas resources confirmed and strengthened the exploration expection of Sinian to Lower Paleozoic carbonate rocks in the eastern Tarim Basin,and would promote the exploration of the two realistic plays,Tadong uplift and Gucheng low uplift,and the evaluation of three potential plays.

关 键 词：塔东地区 震旦系—下古生界 原油裂解气 分散液态烃接力生气 规模储层 勘探领域 

分 类 号：TE122.2[石油与天然气工程—油气勘探]