用地层元素测井资料确定储层粘土含量

地层元素测井 (ECS)是一种实时测量地层中元素含量的新型测井方法。介绍了ECS的方法和原理 ,根据王庄油田 4口井的ECS资料及氧化物闭合模型和综合处理解释结果 ,确定出该区的地层矿物含量 ,依据矿物含量并结合自然伽马能谱测井方法确定出研究区的粘土含量及类型。结果表明 ,研究区沙三段碎屑岩储层粘土矿物以伊 /蒙混层为主 ,其含量平均为 5 0 % ;其他矿物含量依次为 :高岭石平均为 2 0 % ,伊利石平均为 15 % ,绿泥石平均为 8%。伊 /蒙混层比平均为 76 % ,粘土成分以蒙脱石为主。将测井解释得到的粘土含量及类型与X 衍射分析结果进行了对比 ,验证了测井解释结果的可靠性。根据研究区的粘土含量和类型 ,提出了该区储层改造时应采用的几项措施。

Determination of content of clay mineral in formation using elemental capture spectroscopy

The element capture spectroscopy (ECS) is a new logging method for real-time measurement of element content in formation. The principles of ECS were introduced. The mineral content of the formation in Wangzhuang Oilfield was determined, according to the ECS data from four wells and by using closed oxide model and comprehensive interpretation techniques. The type and contents of clay mineral in study area were determined by combining mineral contents with the results of natural gamma-ray spectrum log. The results show that the clay mineral in the clastic reservoir of Es_3 is mainly illite-smectite layer which occupies 50% averagely, and others in turn are kaolinite of 20%, illite of 15% and chlorite of 8% averagely. The illite-to-smactite ratio reaches 76%. The montmorillonite is the main component in clay mineral. The logging interpretation results are reliable by correlating the results of X-ray diffraction analysis. Several measures for improving the property of the reservoir in Wangzhuang Oilfield are suggested, according to the clay types and contents obtained with ECS.