摘要
化学滴定法测量阳离子交换能力(CEC)值存在缺陷。介绍了易操作的CEC值测量新方法———光度分析法的测量原理、步骤及优点。对粘土样的重复测量结果表明,平均绝对误差仅为1.052mmol/100g,标准差为1.21mmol/100g,准确度高。对比2种方法测量的泥质砂岩岩样(7块)的CEC值时发现,二者一致性较好,光度分析法测量CEC值略高,约3%。为检验光度分析法在泥质砂岩储层含油性评价中的应用效果,选取Z盆地LX井区的××层系泥质砂岩储层,由QV和自然伽马测井资料建立了由泥质含量估算QV的统计模型,使用WaxmanSmits模型估算了储层含油饱和度,与密闭取心的饱和度分析资料符合得较好,含油饱和度的估算误差在5%以内。推荐光度分析法作为一种实验室测量岩样CEC值的常规方法。
The negative influence from chemistry and operator on the measurement of cation exchange capability (CEC) with titration method is analysed. A new method, absorbency method, which can overcome the influence and is easy in operation is introduced. A clay sample is measured repeatedly. The measured result shows that its veracity is so high that average absolute error is only 1052 mmol/100 g and standard deviation is 121 mmol/100 g. The CEC values of 7 shaly sandstone samples measured by titration method and absorbency method are compared, the result from which shows a very good coherence and the CEC measured by absorbency method is about 3% higher than that of titration method. At last, in order to verify absorbency method's effect on the estimation of oil and gas saturation, the shaly sandstone reservoir of ×× layer of LX well area of Z basin is selected. A Model between Q_V and GR logging curve is set up. With the Waxman-Smits model, the oil saturation is estimated, and compared to the saturation measured from sealed rock samples, the estimated saturation is approximate to the measured one and their error is within 5%. So, the absorbency method can be used as a routine CEC measuring method.
出处
《测井技术》
CAS
CSCD
2005年第3期199-202,共4页
Well Logging Technology
