南方海相油气勘探中的烃源条件分析——以江汉平原区为例

ANALYSIS OF HYDROCARBON SOURCE CONDITIONS IN MARINE FACIES PETROLEUM EXPLORATION IN SOUTH CHINA-A CASE STUDY IN THE JIANGHAN PLAIN REGION

罗开平 丁道桂 吕剑虹 刘光祥

Luo Kaiping Ding Daogui Lü Jianhong Liu Guangxiang

同济大学, 上海, 200092 2. 中国石油化工股份有限公司, 石油勘探开发研究院无锡石油地质研究所, 江苏, 无锡, 214151

Tongji University, Shanghai 200092, China 2. Wuxi Research Institute of Petroleum Geology, Research Institute of Petroleum Exploration and Production, SINOPEC, Wuxi, Jiangsu 214151, China

中国南方海相油气地质条件和特点给烃源条件分析提出了新内容和新要求。对于晚期成藏来说,烃源岩的时效性比其原有品质条件更为重要,烃源条件分析和烃源岩评价应该打破"唯指标论"的习俗,立足于烃源岩演化史研究,突出"阶段性"和"时效性"分析,在确定有效烃源岩及其发育区的基础上,进行资源潜力分析并指导对勘探目标的选择。对于以晚燕山—早喜山期重建的封存体系为主要勘探对象的江汉平原区海相,断陷盆地的叠覆是促成二叠系烃源岩成熟和下古生界烃源岩二次(晚期)生烃的主要原因。初步研究表明,二叠系(碳酸盐岩)烃源岩为主要的有效烃源岩,其次为上奥陶统五峰组—下志留统龙马溪组烃源岩;而主要的供烃区则是江陵凹陷、潜江凹陷等几个晚期断陷深凹的地区。

Geologic conditions and characteristics of marine facies petroleum in South China have put forward new contents and requirements for petroleum source condition analysis.For late accumulations,prescription of source rocks is more important than their original characters.Spurning the former rules which adhere to parameters,source condition analysis and source rock evaluation should be based on source rock evolution history research and focus on stage and prescription studies.When effective source rocks and generation regions are confirmed,exploration targets can be chosen.In marine facies strata in the Jianghan plain region,sealing system rebuilt from late Yanshanian to early Himalayan period is the main exploration target.Superimposition of rift-subsidence basins makes Permian source rocks become mature and Lower Paleozoic source rocks again produce petroleum.Permian carbonate source rocks are the main effective source rocks.From Wufeng Formation of Upper Ordovician to Longmaxi Formation of Lower Silurian is the second effective.Main source regions locate in the Jiangling and Qianjiang sags.

https://doi.org/10.11781/sysydz200802133