乌尔逊凹陷含片钠铝石地层水特征及成因  

Chemical features and origin of dawsonite-bearing stratum water in Wuerxun sag

作　　者：曲希玉[1] 刘立[1] 王志国[2] 刘剑营[1] 许岩[3] 

机构地区：[1]吉林大学地球科学学院,吉林长春130026 [2]大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712 [3]中国石油天然气集团公司上海浦东华油公司,上海200122

出　　处：《大庆石油学院学报》2006年第5期7-10,共4页Journal of Daqing Petroleum Institute

基　　金：国家自然科学基金项目(40372060)

摘　　要：片钠铝石是一种对油田开发有害的酸敏性矿物,其形成于碱性条件时需要大量的CO2及富含钠铝硅酸盐矿物及有一定孔隙空间的储层;在乌尔逊凹陷南屯组有多口井含有此矿物.对研究区白垩系各层位地层水特征对比发现,南屯组含片钠铝石地层水具有高矿化度,高Na+,K++Na+,HCO3-,CO32-质量浓度的特点,其成因与片钠铝石的形成密切相关.研究区含片钠铝石钻井分布于深大断裂和γ5花岗岩附近,沿深大断裂运移至南屯组的大量CO2,溶于地层水形成碳酸水溶液,使地层水中HCO3-质量浓度增加;同时酸性水长石,致使Na+,K+,Ca2+等增多,部分Na+与Al3+和HCO3-结合生成片钠铝石,而部分Ca2+将会与CO32-结合形成碳酸盐胶结物,使得含片钠铝石地层水具有高矿化度和高Na+,K++Na+,HCO3-,CO32-质量浓度的特点.The dawsonite is a mineral sensitive to acidic substance,it requires alkali conditions to develop,in formation with much CO_2 and the reservoir containing much silicate mineral rich in sodium and aluminum,and containing certain pore space.This mineral is found in many wells of Nantun group in Wuerxun depression.Comparison of the features of formation water in every horizon of Cretaceous in the target areas shows that the formation water containing dawsonite of nantun group has been highly mineralized,and has a higher density of Na^+,K^++Na^+,HCO^-_3,CO^(2-)_3,the reason of this is closely related to the formation of the dawsonite.The driven wells of the target areas containing dawsonite are near to the great deep fracture and γ5granite.A lot of CO_2 moving to Nantun group along the great deep fracture,dissolves in formation water and forms carbonic water solution,this makes the amount of HCO^-_3 increasing.At the same time acidic water replaces feldspar,in this way the amount of these ions such as Na^+,K^+,Ca^(2+) increases.Part of Na^+ and Al^(3+) combined with HCO^-_3 generates dawsonite,however,part of Ca^(2+) combined with CO^(2-)_3 generates carbonate agglutinate,which makes dawsonite formation water possess the features mentioned above.

关 键 词：鸟尔逊凹陷 地层水 片钠铝石 化学特征 成因 

分 类 号：P571[天文地球—矿物学]