高邮凹陷南部真武地区地层水化学特征与油气运聚的关系  

Hydrochemical properties of formation water and its relationship with oil and gas migration and accumulation in Zhenwu area of southern Gaoyou sag

作　　者：李梅[1,2] 金爱民[1,2] 楼章华[1,2] 尚长健[3] 关弛[1,2] 

机构地区：[1]浙江大学水文与水资源工程研究所 [2]浙江大学海洋研究中心,浙江杭州310058 [3]浙江大学地球科学系,浙江杭州310027

出　　处：《中国石油大学学报（自然科学版）》2010年第5期50-56,共7页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家自然科学基金联合化工重点项目(40839902);国家“973”重点基础研究发展规划项目(2005CB422107)

摘　　要：在分析高邮凹陷许庄、真武和曹庄油田地层水化学垂向和平面分布特征的基础上,考察地层水成因及油田水化学特征与油气运聚的关系。结果表明:许庄油田大气水间断性下渗,下渗深度可能达到2.5～3.0km;真武和曹庄油田地层水成因主要为沉积埋藏水,但越流模式不同;高邮凹陷南部真武地区地层水化学场由南向北可划分为大气水下渗淋滤淡化区、汇合越流浓缩区和泥岩压实排水淡化区;研究区南部真武大断裂长期活动,大气水下渗淡化地层水,矿化度较低,油气成藏—保存条件较差,而北部地层水明显受泥岩压实排水淡化作用的影响,矿化度较低;地层水在离心流运移过程中不断越流浓缩,矿化度逐渐增大,部分油气随地层水二次运移途中遇到合适的圈闭逐渐聚集起来形成油气藏;中部汇合越流浓缩区为北部泥岩压实排出水和南部下渗大气水的共同指向区,地层水矿化度较高,有利于油气聚集成藏,且富集程度较高。Based upon the analysis of vertical and horizontal distribution properties of formation water chemistry in Xuzhuang,Zhenwu and Caozhuang oilfields of Gaoyou sag,the origin of formation water and the relationship between hydrochemistry and oil and gas migration and accumulation were thoroughly studied. The results show that meteoric water infiltrated discontinuously in Xuzhuang oilfield,and the infiltration depth may reach 2 500-3 000 m. The origin of formation water in Zhenwu and Caozhuang oilfields is sedimentary burial water,but their over flow patterns are different. The hydrochemistry field of Zhenwu areas in southern part of Gaoyou sag can be divided into three parts： ①freshening zone due to meteoric water leaching downwards; ②concentration zone due to cross-formational flow; ③freshening zone due to compaction-released water. In the south,meteoric water infiltrated due to the long term activity of Zhenwu fault. The mineralization of formation water is lower as the desalination of infiltrated meteoric water,and the hydrocarbon accumulation and preservation conditions are poor. The northern part,obviously affected by the desalting of compaction-released water,has low mineralization of formation water. However,the formation water concentrated and its mineralization increased gradually during the process of centrifuge over flow. The part of the oil and gas could be preserved in appropriate trap in the path of secondary migration along with the formation water. The concentration zone due to cross-formational flow in the middle part,with high mineralization degree offormation water,is the common point area of northern part mudstone compaction-released water and southern part meteoric water infiltration. It is favorable to oil and gas accumulation,and the degree of enrichment is higher.

关 键 词：高邮凹陷 地球化学 油田水 地层水化学 垂向分布 平面分布 油气运聚 

分 类 号：TE144[石油与天然气工程—油气勘探]