密度测井仪灵敏探测位置及对薄层响应的理论研究

On Sensitive Detecting Location of Densilog Tool and Its Responses to Thin Beds.

用蒙特卡罗方法研究密度测井仪对不同厚度高 /低密度薄层的响应 ,得到了长源距探测器计数随薄层位置变化而变化的关系。由模型模拟结果得出 ,密度测井仪探测器灵敏探测位置是在源与探测器之间的中点 ,探测器对薄层的响应曲线左右对称 ,低密度薄层在响应曲线上出现极大值 ,薄层厚度越大 ,其极值越大 ;高密度薄层在响应曲线上出现极小值 ,薄层厚度越大 ,其极值越小 。

By Monte Carlo method, this article studies the response of density logging tool to thin beds that have various thickness and high or low density, from which is gained the relationship between detector tallies and lamina location. The modeled result is that the sensitive detecting location of density logging tool is the midpoint between detector and source, and theoretically, it's so, too. Log responses of the detector to thin beds are symmetric side to side. Thin beds with low density show maximum value on the response curves, the thicker the thin bed is, the higher the maximum value is. But, thin beds with high density show minimum value on the response curves, the thicker the thin bed, the lower the maximum value.