塔中北斜坡奥陶系鹰山组地层水特征与油气保存条件  

Characteristics of Formation Water of Ordovician Yingshan Formation in the Northern Slope of Tazhong Palaeouplift and Condition of Hydrocarbon Preservation

作　　者：王祥[1] 韩剑发[2] 于红枫[2] 刘丹丹 张金辉 吕修祥[1] 华晓莉[1] 

机构地区：[1]中国石油大学(北京)地球科学学院油气资源与探测国家重点实验室,北京102249 [2]中国石油塔里木油田分公司,新疆库尔勒841000 [3]中海石油(中国)有限公司天津分公司,天津300452

出　　处：《石油天然气学报》2012年第5期25-29,2-3,共5页Journal of Oil and Gas Technology

基　　金：国家自然科学基金项目(41072102)

摘　　要：通过对塔中北斜坡鹰山组地层水的矿化度、主要离子浓度和化学指数的统计分析,讨论了该区地层水的成因及与油气保存条件。研究结果表明,塔中北斜坡鹰山组地层水为高矿化度CaCl2型水,总矿化度约为80～200g/L,阴、阳离子分别以Cl-和K++Na+为主。剖面上总矿化度随深度增加逐渐变小,平面上地层水矿化度自塔中I号断裂向南增高。高矿化度、富K++Na+和Cl-离子的特征表明地层水的形成与浓缩变质作用或碳酸盐岩矿物溶解有关。钠氯系数值和脱硫系数与矿化度均成负相关关系,高矿化度、低钠氯系数、低脱硫系数,说明该区整体油气保存条件较好。区域上,中古5井-中古7井区地层水封闭性优于其他井区,更有利于油气的保存。The characteristics of formation water of Yingshan Formation in the northern slope of Tazhong Palaeouplift and its relationship with hydrocarbon preservation condition were discussed through analyses of salinity,ion concentration and its chemical coefficients.The results indicates that the formation water is of CaCl2 type with high salinity ranging from 80 to 200 g/L,and contains mainly cations K++Na+ and anion Cl-.Longitudinally,the salinity decreases along with depth,horizontally,the salinity increases from Tazhong Depression I to the south.High salinity and K++Na+ and Cl-concentrations indicate that the genesis of formation water is related with concentration metamorphism and carbonate mineral dissolution.Low sodium-chlorine coefficient and coefficient of desulfurization demonstrate that the northern slope of Tazhong Palaeouplift is in good preservation condition,regionally,the sealing condition of Zhonggu Wellblock 5-7 is superior to other ones,and is more beneficial for hydrocarbon preservation.

关 键 词：矿化度 地层水 化学参数 油气保存 塔中北斜坡 

分 类 号：P618.13[天文地球—矿床学]