摘要
本文根据自然电位形成的机理,建立了简化模型,推导出了自然电流增大系数(油层水淹后的自然电流与油层水淹前的自然电流之比)与地层含水饱和度、地层水电阻率等参数关系的表达式。根据计算结果得出的结论是油层水淹后自然电流增大系数并不总是大于1。根据自然电流的含义,采样电阻越小越好。这种情况下可采用低输入阻抗放大器和梯度法来测量自然电流。利用这样的装置已获得了现场测井资料。
ABSTRACT
On the basis of mechanism of spontaneous logging,a simple model is establs-hed and a relatiouship between incremental factor of spontaneous current (the ratio of spontaneous currents of pre and post watered out zones) and water saturation, formation water resistivity is derived. The results of calculation show that the incremental factor of spontaneous current after oil zones watered out is not always greater than 1. According to the definition of spontaneous current, the smaller sampling resistance the better and in this case it is possible to use low input impedance amplifier and gradient method to measure spontaneous current. Field logging data have already been obtained by using this device.
出处
《大庆石油地质与开发》
CAS
CSCD
北大核心
1989年第1期69-74,62,共7页
Petroleum Geology & Oilfield Development in Daqing
