涠西南凹陷C洼油气成藏动力学过程与充注历史  

DYNAMIC PROCESSES OF HYDROCARBON ACCUMULATION AND CHARGING HISTORY OF C SAG IN WEIXINAN DEPRESSION

作　　者：王修平[1,2] 叶加仁[1] 孙建峰 吴娟[1] 

机构地区：[1]中国地质大学构造与油气资源教育部重点实验室,武汉430074 [2]中国石化上海海洋油气分公司研究院,上海200120 [3]陕西延长石油有限责任公司研究院,西安710075

出　　处：《海洋地质与第四纪地质》2010年第5期101-107,共7页Marine Geology & Quaternary Geology

基　　金：国家科技重大专项(2008ZX0500-23-01);中国石化上海海洋油气分公司科研项目"北部湾中石化区块重点凹陷油气成藏规律研究"

摘　　要：以油气成藏体系及成藏动力学理论为指导,在成藏基本地质要素分析的基础上,综合各种地质、地球物理、地球化学等资料,采用盆地数值模拟与油气地质综合分析相结合的研究方法,分析了涠西南凹陷C洼的流体动力场特征,动态重建了油气成藏动力学过程,恢复了流体充注历史。结果表明:C洼地区具有较高的地温梯度,流沙港组二段发育有异常超压,古今流体势分布具有较大的继承性;该区沉积充填与构造沉降具幕式变化特征,流二段烃源岩目前处于成熟—高成熟阶段,具有较高的生排烃速率,主要生排烃过程发生于中新世以来;C洼地区经历多次油气充注过程,其中东北部以早期为主,西南部以晚期充注为主。Taking account of the theories of petroleum accumulation system（PAS） and petroleum accumulation dynamics, based on the characteristics of the PAS, the characteristics of the fluid dynamic field in C sag within the Weixinan Depression have been analyzed. Geological, geophysical and geochemical data were used,and basin modeling technique and petroleum geological colligation research methods adopted in the research. As the results,the petroleum accumulation processes were studied dynamically, and the hydrocarbon charging history was renewed. It suggests that the C Sag has higher geothermal gradient in the Second Member of the Liushagang Formation, with a fluid potential inherited from history. The sedimentation and tectonic subsidence show an episodic manner. The source rock of the Second Member of the Liushagang Formation had entered the period of mid high maturity and had higher rate of hydrocarbon generation-expelling. The main episode of hydrocarbon generation-expelling happened after Miocene. It is believed that C Sag had passed several times of hydrocarbon charging. The Northeast part was charged earlier and the Southwest part later.

关 键 词：成藏地质要素 流体动力场 成藏动力学过程 充注历史 涠西南凹陷 

分 类 号：P744.4[天文地球—海洋科学]