摘要
源内和源外油气成藏过程存在显著差异,导致二者对烃源灶的要求明显不同。基于中国陆相已知常规油藏的源-藏对应关系和页岩油烃源灶特征研究,论证常规油藏与页岩油的烃源灶差异性。常规油气藏大多数都分布在源外,其形成是油气受浮力作用发生由分散到富集的过程,油气聚集不一定需要很高的母质丰度,但需要较高的排烃效率和排烃量,烃源岩TOC门限值为0.5%,最佳区间为1%~3%。源内油气藏以页岩油气为主,是油气在源内的滞留,缺少大规模运移富集过程,对烃源岩质量和规模要求更高。中高成熟度页岩油TOC门限值为2%,最佳区间为3%~5%,中低成熟度页岩油TOC门限值为6%,且越高越好;有机质类型以Ⅰ—Ⅱ_(1)倾油型有机质为宜。开展烃源岩品质与分级评价,寻找规模优质烃源岩富集区和富集段,是油气勘探从源外进入源内必须关注的科学问题,目的是为即将到来的页岩油富集区选区和选段、经济发现与客观评价资源潜力等提供理论指导。
Because of the differences of hydrocarbon accumulation between in-source and out-of-source oil pools,the demand for source kitchen is different.Based on the establishment of source-to-reservoir correlation in the known conventional accumulations,and the characteristics of shale oil source kitchens as well,this paper discusses the differences of source kitchens for the formation of both conventional and shale oils.The formation of conventional oil pools is a process of hydrocarbons enriching from disperse state under the action of buoyancy,which enables most of the oil pools to be formed outside the source kitchens.The source rock does not necessarily have high abundance of organic matter,but has to have high efficiency and enough amount of hydrocarbon expulsion.The TOC threshold of source rocks for conventional oil accumulations is 0.5%,with the best TOC window ranging from 1%to 3%.The oil pools formed inside the source kitchens,mainly shale oil,are the retention of oil and gas in the source rock and there is no large-scale hydrocarbon migration and enrichment process happened,which requires better quality and bigger scale of source rocks.The threshold of TOC for medium to high maturity of shale oil is 2%,with the best range falling in 3%-5%.Medium to low mature shale oil resource has a TOC threshold of 6%,and the higher the better in particular.The most favorable kerogen for both high and low-mature shale oils is oil-prone type of I-II_(1).Carrying out source rock quality and classification evaluation and looking for large-scale and high-quality source rock enrichment areas are a scientific issue that must be paid attention to when exploration activity changes from out-of-source regions to in-source kitchen areas.The purpose is to provide theoretical guidance for the upcoming shale oil enrichment area selection,economic discovery and objective evaluation of resource potential.
作者
赵文智
张斌
王晓梅
吴松涛
张水昌
刘伟
王坤
赵霞
ZHAO Wenzhi;ZHANG Bin;WANG Xiaomei;WU Songtao;ZHANG Shuichang;LIU Wei;WANG Kun;ZHAO Xia(Research Institute of Petroleum Exploration and Development,PetroChina,Beijing 100083,China;College of Geosciences,China University of Petroleum(Beijing),Beijing 102249)
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2021年第3期464-475,共12页
Petroleum Exploration and Development
基金
国家科技重大专项(2016ZX05046,2017ZX05001)
中国石油勘探开发研究院科学研究与技术开发项目(2018ycq02)。
关键词
常规油气藏
源外聚集
页岩油
源内滞留
烃源灶差异
有机质丰度
陆相
优质烃源岩
conventional oil reservoirs
out-source accumulation
shale oil
in-source hydrocarbon residue
source kitchen differences
organic abundance
lacustrine
high-quality source rock
