高温高压NaCl溶液低频复导电特性的测量

Measurements of Low frequency Complex Resistance of NaCl Solution Under High Temperature and High Pressure

陈福煊，张开洪，陈一健．高温高压ＮａＣｌ溶液低频复导电特性的测量．测井技术，１９９７，２１（１）：１５～１９用新近开发的高温高压地层水电阻率测量装置测量ＮａＣｌ溶液的高温高压低频复导电特性。常温常压测量结果与美国２５个实验室［１］测量数据基本一致；不同温度和浓度的ＮａＣｌ溶液电阻率的测量结果与斯仑贝谢公司的测量图版所得结果基本一致。但其测量结果同时表明，除浓度和温度外，测量频率（１２Ｈｚ～１００ｋＨｚ）和加在溶液上的压力对淡水电阻率影响很大，相对偏差可达±５０％。溶液电阻率随频率和内压的增加而降低。因此，在淡地层水油田或淡水驱油层用电阻率测井资料计算含油饱和度时，应考虑测量频率和地层压力对地层水电阻率的影响。

Low frequency complex resistance of NaCl solution is measured under HT & HP with a newly developed formation water resistivity measuring system. The measured results from this system under ambient conditions are almost the same as those from 25 labs of U.S.A.. The measured resistivities of NaCl solution with different temperatures and concentrations are consistent with those from the charts of Schlumberger. However, the above measured results show that resistivities of water are strongly influenced by measuring frequency (12 Hz～100 kHz) and pressure acting on the solution in addition to concentration and temperature, which can result in a relative deviation of ±50% at most. Resistivity of the solution decreases with the increase of frequency and pressure. Therefore, in oilfields with fresh formation water or fresh water drive ones, the influence of measuring frequency and formation pressure on formation water resistivity should be considered while computing oil saturation with resistivity logging data.