摘要：The discovery and large-scale exploration of unconventional oil/gas resources since 1980s have been considered as the most important advancement in the history of petroleum geology; that has not only changed the balance of supply and demand in the global energy market, but also improved our understanding of the formation mechanisms and distribution characteristics of oil/gas reservoirs. However, what is the difference of conventional and unconventional resources and why they always related to each other in petroliferous basins is not clear. As the differences and correlations between unconventional and conventional resources are complex challenging issues and very critical for resources assessment and hydrocarbon exploration, this paper focused on studying the relationship of formations and distributions among different oil/gas reservoirs. Drilling results of 12,237 exploratory wells in 6 representative petroliferous basins of China and distribution characteristics for 52,926 oil/gas accumulations over the world were applied to clarify the formation conditions and genetic relations of different oil/gas reservoirs in a petroliferous basin, and then to establish a unified model to address the differences and correlations of conventional and unconventional reservoirs. In this model, conventional reservoirs formed in free hydrocarbon dynamic field with high porosity and permeability located above the boundary of hydrocarbon buoyancy-driven accumulation depth limit. Unconventional tight reservoirs formed in confined hydrocarbon dynamic field with low porosity and permeability located between hydrocarbon buoyancy-driven accumulation depth limit and hydrocarbon accumulation depth limit. Shale oil/gas reservoirs formed in the bound hydrocarbon dynamic field with low porosity and ultra-low permeability within the source rock layers. More than 75% of proved reserves around the world are discovered in the free hydrocarbon dynamic field, which is estimated to contain only 10% of originally generated hydrocarbons. Most of undiscovered resources distributed in the confined hydrocarbon dynamic field and the bound hydrocarbon dynamic field, which contains 90% of original generated hydrocarbons, implying a reasonable and promising area for future hydrocarbon explorations. The buried depths of hydrocarbon dynamic fields become shallow with the increase of heat flow, and the remaining oil/gas resources mainly exist in the deep area of "cold basin" with low geothermal gradient. Lithology changing in the hydrocarbon dynamic field causes local anomalies in the oil/gas dynamic mechanism, leading to the local formation of unconventional hydrocarbon reservoirs in the free hydrocarbon dynamic field or the occurrence of oil/gas enrichment sweet points with high porosity and permeability in the confined hydrocarbon dynamic field. The tectonic movements destroy the medium conditions and oil/gas components, which leads to the transformation of conventional oil/gas reservoirs formed in free hydrocarbon dynamic field to unconventional ones or unconventional ones formed in confined and bound hydrocarbon dynamic fields to conventional ones.

关键字：Fossil fuels; Hydrocarbon resources; Unified model of reservoirs formation; Hydrocarbon reservoirs; Hydrocarbon accumulation; Hydrocarbon dynamic field

ISSN号：1674-9871

卷、期、页：卷: 12期: 2页: 695-711

发表日期：2021-03-01

影响因子：4.201800

期刊分区（SCI为中科院分区）：一区

收录情况：SCI（科学引文索引印刷版）,SCIE（科学引文索引网络版）

发表期刊名称：GEOSCIENCE FRONTIERS

参与作者：贾承造,黎茂稳,胡钦红,陈掌星,刘可禹

通讯作者：汪文洋,郭迎春,彭俊文

第一作者：庞雄奇,陈君青,吴克柳

论文类型：期刊论文

论文概要：庞雄奇,贾承造,陈君青,黎茂稳,汪文洋,胡钦红,郭迎春,陈掌星,彭俊文,刘可禹,吴克柳，A unified model for the formation and distribution of both conventional and unconventional hydrocarbon reservoirs，GEOSCIENCE FRONTIERS，2021，卷: 12期: 2页: 695-711

论文题目：A unified model for the formation and distribution of both conventional and unconventional hydrocarbon reservoirs