塔里木盆地北部油田水特征离子及意义

CHARACTERISTIC IONS OF OILFIELD WATER IN NORTHERN TARIM BASIN AND ITS SIGNIFICANCE

周晓芬

Zhou Xiaofen

塔里木盆地北部西达里亚、塔河1号及塔河3,4号油田的油田水具有相近的离子组成,其可溶物质主要成分与海水一致,表明其主要为海相成因。油田水中不同的离子组成及浓度指示特定的地质意义:HCO与地层密度具有良好的正相关关系,地层时代愈老,直线斜率愈大;SO,Ca,Mg浓度的差异预示油田水的不同来源;I含量不受地层岩性影响,而由原油物性决定,I含量高,则原油物性就好;Br浓度大于350mg/L的油田水则是凝析油的特征。

The oilfield water in xidaliyia,Tahe-1,Tahe-3 and Tahe-4 Oilfields in Northern Tarim Basin has similar ionic composition,and the principal compositions of soluble materials are consistent with sea water,suggesting its marine origin.The different ionic compositions and concentration indicate different geological features.HCO has positive coherence with the strata density,the concentration differences of SO,Ca,Mg indicate different origin of the water.The content of I is determined by physical features of crude oil but not lithologic feature,and bears negative coherence with the density of crude oil.When concentration of Br in oilfield water is more than 350 mg/L,the oil would be condensate oil.

10.11743/ogg20000423