叠合盆地油气系统研究方法——以中国南方中、古生界为例

通过南方中、古生界油气地质综合研究及勘探成果总结,初步提出一套叠合盆地或改造型盆地评价及其油气系统的研究方法.其核心思路是强调进行油气地质“动态演化”研究.主要通过拟三维盆地模拟反演主要烃源岩时空演化、生烃过程及其不同地质阶段中的生烃强度、资源量;结合古今油气藏解剖分析总结油气成藏-破坏规律及古构造分析研究油气运聚指向;结合主要构造运动期对南方中、古生界主要油气系统进行了分阶段的动态演化研究.认为南方中、古生界油气勘探的现实对象是次生油气系统及再生烃油气系统,现存的原生油气系统很少.提出南方新区中、古生界油气勘探有利区为川东北大巴山前缘及石柱复向斜西侧高陡背斜带、苏北盆地阜宁-盐城-海安-兴化-宝应地区、江汉盆地沉湖地区南部潜江-仙桃-牌州-汊参1井地区、江西南鄱阳盆地及楚雄盆地北部凹陷.这一认识已经得到苏北盆地盐城凹陷朱家墩气田及江汉盆地沉湖地区南部开先台西含油构造勘探发现的证实.

THE STUDYING METHOD OF PETROLEUM SYSTEM IN SUPERPOSITION BASIN—AS AN EXAMPLE BY ANALYZING MESOZOIC ＆ PALEOZOIC IN SOUTHERN CHINA

By synthetically studying the petroleum geology features of Mesozoic & Paleozoic in southern China and reviewing the exploration history,this paper tentatively bring forward the studying method about evaluating the superposition or transformed basins and its petroleum system.The core thoughts are emphasizing to proceed the dynamic evolution studies of petroleum geology.Chiefly by the quasi 3D basin modeling deduces the spatio temporal evolution,process of hydrocarbon yielding and intenstiy of hydrocarbon production or source quantity in distinct geological stages of chief source rocks.Through analyzing the past & existent oil gas fields,we can sum up the rules of oil gas fields formation or destruction.And the direction of oil gas migration & accumulation can be deduced from paleo tectonic analysis.It is studied that the dynamic evolution of chief Mesozoic & Paleozoic petroleum systems in southern China regarding the main stages of tectonic movements.Authors suggest the realistic targets of Mesozoic & Paleozoic oil gas exploration in southern China are secondary and hydrocarbon regeneration petroleum systems,and the existent primary petroleum systems are very few.The perspective regions to explore Mesozoic & Paleozoic oil gas fields in southern China as frontier areas are NE Sichuan (the foreland of Daba mountain)and western cliffy anticline belts of Shizhu synclinorium,Funin Yancheng Haian Xinhua Baoyin area in northern Jiangsu Basin,Qianjiang Xiantao Paizhou well Chacan 1 area in southern part of Jianghan Basin,southern Poyang Basin in jiangxi,and northern depression of Chuxiong Basin.This conclusion is already approved by discovering the Zhujiadun gas field in Yancheng sag of northern Jiangsu Basin and Kaixiantaixi oil bearing trap in southern part of Jianghan Basin.