元素俘获谱测井识别高伽玛砂岩储层

在砂泥岩剖面中，泥岩往往具有较高的自然伽玛值，而砂岩的自然伽玛值较低。自然伽玛测井曲线在测井解释中的一个重要应用就是划分岩性，从而将砂岩储层从钻井剖面中划分出来。但是由于储层沉积环境变化，储层中泥质类型发生变化，或储层中舍有某些放射性较强的矿物，往往形成高伽玛砂岩储层。这类储层与泥岩的自然伽玛值相差不大，往往造成将高伽玛砂岩储层解释为干层的结果。元素俘获谱测井通过测量地层不同元素的俘获谱，经过拟合计算得出地层中不同元素的含量，可以较准确地识别高伽玛砂岩储层。

Application of Element Capitation Spectroscopy Logging in Changqing Gas Exploration

Shale formation has high gamma ray and sand formation has low gamma ray in shale-sand formation profile.So we can distinguish shale formation and sand formation with gamma ray.But some kinds of sand formation have high gamma ray because clay style changed and formation include some high radiation element.ECS logging can effectively distinguish this kind of sand formation through measurement formation element capitation spectroscopy.