元素俘获谱测井元素相对灵敏度研究

摘要

地层元素俘获谱测井可直接、准确判断岩性，为识别复杂储层岩性、确定骨架密度、解释沉积环境、根据矿物组成计算孔隙度及渗透率等问题的解决提供了一种新的途径。而求取组成地层岩石的各元素相对灵敏度是地层元素俘获谱测井解释的关键所在。文章结合研制的地层元素俘获谱测井仪，用蒙特卡罗数值模拟的方法对其建立数值模型，并进行优化验证，得到理想的模型，进一步建立已知元素成分的刻度模拟井，计算得到硅、硫、钙、铁、钛、钆、氢和氯等元素的相对灵敏度，并与斯伦贝谢公司的地层元素测井仪的相对灵敏度比较分析，确定了可用于求解骨架元素含量计算的元素相对灵敏度，这一结果解决了元素俘获谱测井仪求解地层各元素含量分析过程中的技术难点。%Elemental capture spectroscopy log can directly and accurately determine complex lithology, which provides a new approach to i-dentifying complex lithology, determining the density of framework, interpreting the sedimentary environment, calculating porosity and per-meability according to the mineral composition. Measuring the relative sensitivity factor of lithology is the key to elemental capture spectros-copy log interpretation. In this paper, we established the model of the formation element captured spectrum logging tool with Monte Carlo method and by optimization obtained the ideal model. We also established the element standard simulation well to calculate and obtain the relative sensitivity factor of sulfur, calcium, silicon, iron, titanium, gadolinium, hydrogen, chlorine, and other elements. Compared with the relative sensitivity factor of Schlumberger elemental capture spectroscopy log,we obtained the relative sensitivity factor which can be used to calibrate the elemental weight fractions in data processing. This method solved the key problem of conversion from yield of each element to the weight fractions in the data processing.