大油气区的内涵、分类、形成和分布

基于对全球油气分布规律的分析,提出了大油气区的概念:大油气区处于统一的构造动力学背景中,由一系列在成因、类型和分布方面相联系或相关的油气区、油气聚集带构成,其范围可以比盆地(或凹陷)大,也可以比盆地小,其有利构造背景、优质烃源岩、有利储集层、有效区域性盖层都基本相似,储量规模较大。统一的构造动力学背景和相似的成藏条件是形成大油气区的基础,原型盆地或凹陷(群)类型是划分大油气区的基本依据。中国地跨环太平洋主动型大陆边缘巨型油气域和大陆板块挤压碰撞型巨型油气域,目前共发现4个大油区、7个大气区和1个大油气区。根据大油气区的形成条件和特征,在勘探研究战略上,应坚持“立足长远,着眼全局”的思想、“整体研究、整体部署、整体评价”的原则、“面中找点、以点带面、全面推进”的思路,不因一口井的失利而影响对大油气区勘探的整体推进。大油气区概念的提出旨在强调和促进研究和勘探思路的转变,实现从源控大油气田勘探、复式油气聚集带勘探向大油气区勘探的发展,以大油气区发展带动大油气区建设;同时可为油气输送的管网布局和建设提供依据。图3表3参21

Connotation, classification, formation and distribution of giant oil and gas province

The concept "giant oil and gas province" is coined to describe the petroleum province with big reserve scale that is composed of petroleum provinces and accumulation belts with relations in their generation,type and distribution in the uniform tectonic dynamic settings.It may be smaller or bigger than a basin.Uniform tectonic dynamic settings and similar pool-forming conditions are the basis of forming the provinces,and the basic criterion to divide them is prototype basin or depression type.The provinces have similar tectonic settings,high quality source rocks,favored sedimentary reservoirs and effective regional seals.China steps across the Pacific-surrounding active continental margin and the continental plate collision related giant petroleum domains,and has four giant oil provinces,seven giant gas provinces and one giant oil and gas provinces.The exploration strategy "integrated research,integrated deployment and integrated evaluation" is proposed.The concept is to enhance the transition of research and exploration thinking from finding giant fields to finding giant provinces.