国地质 2020年 ignificant source of oil supply in the world. The geological research, theoretical promoting, and present significant issue oncerning tight oil will supply and prefect geological theory on unconventional hydrocarbon. Currently, the development of geological research on tight oil can be concluded as follows: Three main formation conditions and six basic characteristics about tight oil as well as the differences between continental tight oil in China and marine tight oil in the USa have been summarized. @2 Pore-throat- fracture network in the tight- oil reservoir has been characterized with advanced and high- precision analysis and testing technology, the formation of tight oil being the primary research object. The accumulation mechanism of tight oil has been deeply studied, which includes charge dynamics, the threshold of charging, migration mechanism, accumulating model, etc. Based on the research status about tight oil, this paper puts forward several important questions about tight oil: Holographic quantitative heterogeneity characterization on the tight oil reservoir at a micro-nano scale and its effect on tight oil migration and accumulation; Q the genesis of source-reservoir configuration and its control on tight oil accumulation and enrichment; the influence factors and transformation conditions of the occurrence of tight oil, and the relative contribution of different kinds of occurrence status and space; the internal relationship between the mixed sedimentary system in saline lacustrine basins and the formation of a comprehensive study of the tight oil accumulation factors, and the accumulation mechanism and its whole process. The these questions will play a significant role in geological research on tight oil Key words: tight oil; reservoir characterization; accumulation mechanism; heterogeneity; source- reservoir configuration; occurrence state, mixed sedimentary system; oil-gas exploration engineering About the first author: FANG Xinxin, female, born in 1981, doctor, assistant researcher, mainly engages in the study of reservoir geologyandhydrocarbonaccumulationE-mail:freestarxin(@163.com unconventional oil gas geology and hydrocarbon accumulation; E-mail: cugcupgych(@ 163. o r, mainly engages in the study of About the corresponding author: GUO Yingchun, male, born in 1982, doctor, associate researcl Fund support: Supported by National Natural Science Foundation of China(No. 41602152) 1引言 充,以期起到一定的指导作用 致密油是当前美国原油产量飙升的主要驱动2致密油定义 力,2018年致密油产量3.1×10°t(EA,2018),占总 北美地区的相关机构和媒体发布的报道中所 产量的60%。根据中国石油第4次油气资源评价,提到的致密油或页岩油,并没有太重视其二者的区 全国致密油地质资源量125×10°t,可采资源量13×别,二者含义基本一致。这从有关北美地区致密油 10°t,探明储量约3×l03t(孙龙德等,2019)。截至页岩油的报告或文章中得到印证,不论报告或文章 2018年底,中国陆相致密油已建成产能315.5×10t,中是叫“致密油”还是叫“页岩油”,通常列举的具体 2018年年产量约105×10t(朱如凯等,2019),致密实例几乎是一致的,如 Bakken、 Eagle ford 油已成为中国非常规石油中最现实的领域之一,是 Montrery、 Niobrara、 Cardium、 Montney、 Bashaw等 中国新增石油可采储量和产量的主力军。据预测,( Clarkson and Pedersen,20ll;NEB,2011l; Madden 中国致密油和页岩油的探明可采地质储量和产量 and vossoughi,2013;HA,2018)。目前北美地区流 有望快速上升,到2020年年产量可达5000万t(廖晓行的致密油概念中存在着“轻质( light)”的定语,以 蓉等,2013)。目前致密油地质理论落后于勘探实示和常规油在比重上的区别。究其原因,以目前技 践,亟需构建完备的致密油理论指导其勘探开发,术能在致密类储层中实现经济开发的只能是其中 多位专家针对致密油或非常规油气指出了存在的油质相对轻的部分,另一种原因可能为,致密油的 关键科学问题及发展趋势(王震亮,2013;贾承造富集是石油在源储压差下,被充注入紧邻烃源岩的 等,2014;曾溅辉等,2014),但这些稍偏宏观指导,致密储层中,这种富集方式使得重质油更难在同等 本文在总结致密油成藏研究进展的基础上,结合笔压力条件下充注入致密储层,仅有轻质油才能富 者致密油科研实践,提出针对致密油成藏研究较为集。实际上,致密油和页岩油有着本质的区别(周 细致的科学问题,是对前人提出的科学问题的补庆凡和杨国丰,2012;赵文智等,2020),尽管不同机 http://geochina.cgs.gov.cn中国地质,2020,47(1)http://geochina.cgs.gov.cn 中国地质, 2020, 47(1) significant source of oil supply in the world. The geological research, theoretical promoting, and present significant issues concerning tight oil will supply and prefect geological theory on unconventional hydrocarbon. Currently, the development of geological research on tight oil can be concluded as follows: ① Three main formation conditions and six basic characteristics about tight oil as well as the differences between continental tight oil in China and marine tight oil in the USA have been summarized. ② Pore-throat-fracture network in the tight-oil reservoir has been characterized with advanced and high-precision analysis and testing technology, the formation of tight oil being the primary research object. ③ The accumulation mechanism of tight oil has been deeply studied, which includes charge dynamics, the threshold of charging, migration mechanism, accumulating model, etc. Based on the research status about tight oil, this paper puts forward several important questions about tight oil: ① Holographic quantitative heterogeneity characterization on the tight oil reservoir at a micro-nano scale and its effect on tight oil migration and accumulation; ② the genesis of source–reservoir configuration and its control on tight oil accumulation and enrichment; ③ the influence factors and transformation conditions of the occurrence of tight oil, and the relative contribution of different kinds of occurrence status and space；④ the internal relationship between the mixed sedimentary system in saline lacustrine basins and the formation of tight oil; ⑤ a comprehensive study of the tight oil accumulation factors, and the accumulation mechanism and its whole process. The answers of these questions will play a significant role in geological research on tight oil. Key words: tight oil; reservoir characterization; accumulation mechanism; heterogeneity; source- reservoir configuration; occurrence state; mixed sedimentary system; oil-gas exploration engineering About the first author: FANG Xinxin, female, born in 1981, doctor, assistant researcher, mainly engages in the study of reservoir geology and hydrocarbon accumulation; E-mail：freestarxin@163.com. About the corresponding author: GUO Yingchun, male, born in 1982, doctor, associate researcher, mainly engages in the study of unconventional oil & gas geology and hydrocarbon accumulation; E-mail：cugcupgych@163.com. Fund support: Supported by National Natural Science Foundation of China (No. 41602152). 1 引 言 致密油是当前美国原油产量飙升的主要驱动 力，2018 年致密油产量 3.1×108 t（EIA，2018），占总 产量的60%。根据中国石油第 4 次油气资源评价， 全国致密油地质资源量125×108 t，可采资源量 13× 108 t，探明储量约 3×108 t（孙龙德等，2019）。截至 2018年底，中国陆相致密油已建成产能315.5×104 t， 2018年年产量约105×104 t（朱如凯等，2019），致密 油已成为中国非常规石油中最现实的领域之一，是 中国新增石油可采储量和产量的主力军。据预测， 中国致密油和页岩油的探明可采地质储量和产量 有望快速上升，到2020年年产量可达5000万（t 廖晓 蓉等，2013）。目前致密油地质理论落后于勘探实 践，亟需构建完备的致密油理论指导其勘探开发， 多位专家针对致密油或非常规油气指出了存在的 关键科学问题及发展趋势（王震亮，2013；贾承造 等，2014；曾溅辉等，2014），但这些稍偏宏观指导， 本文在总结致密油成藏研究进展的基础上，结合笔 者致密油科研实践，提出针对致密油成藏研究较为 细致的科学问题，是对前人提出的科学问题的补 充，以期起到一定的指导作用。 2 致密油定义 北美地区的相关机构和媒体发布的报道中所 提到的致密油或页岩油，并没有太重视其二者的区 别，二者含义基本一致。这从有关北美地区致密油/ 页岩油的报告或文章中得到印证，不论报告或文章 中是叫“致密油”还是叫“页岩油”，通常列举的具体 实 例 几 乎 是 一 致 的 ，如 Bakken、Eagle Ford、 Montrery、Niobara、Cardium、Montney、Eashaw 等 （Clarkson and Pedersen，2011；NEB，2011；Madden and Vossoughi，2013；EIA，2018）。目前北美地区流 行的致密油概念中存在着“轻质（light）”的定语，以 示和常规油在比重上的区别。究其原因，以目前技 术能在致密类储层中实现经济开发的只能是其中 油质相对轻的部分，另一种原因可能为，致密油的 富集是石油在源储压差下，被充注入紧邻烃源岩的 致密储层中，这种富集方式使得重质油更难在同等 压力条件下充注入致密储层，仅有轻质油才能富 集。实际上，致密油和页岩油有着本质的区别（周 庆凡和杨国丰，2012；赵文智等，2020），尽管不同机 44 中 国 地 质 2020年