海上油气田油气水层自然电位特征及机理浅析  

Analysis of the Offshore Oil or Gas Reservoirs′ Spontaneous Potential Characteristic and Its Orgins

作　　者：黄导武 刘建新[2] 

机构地区：[1]中海石油有限公司上海分公司,上海200030 [2]中海油田服务股份有限公司,上海200030

出　　处：《测井技术》2006年第2期164-167,共4页Well Logging Technology

摘　　要：渤海油田地层水矿化度低,砂岩自然电位正异常,油(气)层自然电位幅度随含水饱和度增大而增大。南海较多的油气田地层水与海水泥浆滤液矿化度相近,水层自然电位正异常,油(气)层表现为负异常,含烃饱和度越大,负异常幅度越大。自然电场是在地层水与泥浆滤液浓度差作用下发生离子交换而形成的。油(气)层中的水主要是束缚水,与泥浆滤液发生离子交换能力弱,使自然电位幅度随含水饱和度增加而增大。油(气)层含盐量的差异、电阻率的高低也影响自然电位响应特征。根据多地区油(气)水层的自然电位测井曲线特征,提出自然电位与含水饱和度的经验关系式。The oil （gas） reservoir spontaneous potential（SP） curve characteristic differs from water reservoir and is often affected by the difference of formation and mud salinity. SP curve is one of the best way evaluating reservoir fluid property. In Bohai oilfield the salinity of formation is low. The spontaneous potential of sandstone is positive. Oil （gas） reservoir＇s positive spontaneous potential increases with the water saturation increasing. In some Nanhai oilfields the salinity of formation water is close to that of mud filtrate. The spontaneous potential of water reservoir is positive and oil （gas） reservoir is negative. Oil （gas） reservoir＇s negative spontaneous potential increases with the water saturation decreasing. The salinity difference of formation water and mud filtrate causes ion exchange which makes spontaneous electricity. Oil （gas） reservoir＇s formation water is mainly irreducible water which difficultly creates ion exchange with mud filtrate. So the spontaneous potential of sandstone increases with the water saturation increasing. The salinity and resistivity difference between oil （gas） reservoir and water reservoir also influences SP response characteristic. According to all kinds of the spontaneous potential curves from many areas, the experience formula between SP and water saturation Sw is put forward.

关 键 词：自然电位 海上油气田 油气水特征 离子交换 矿化度 含水饱和度 渤海油田 

分 类 号：P631.811[天文地球—地质矿产勘探]