X射线荧光测井谱漂校正技术研究

X射线荧光测井技术是一种可以在井下原位进行元素定量(半定量)分析的测井技术，对矿产勘查具有重要意义。受井下温度影响，X射线荧光测井仪容易发生谱漂。X射线测井仪采用硬件进行稳谱，采用软件实现微小谱漂校正。X射线荧光测井的谱数据量大，难以采用人工校正的方法实现。文章在总结了X射线荧光测量专业人员进行谱漂校正经验的基础上，结合专家系统研究了X射线荧光测井谱漂的校正方法。在谱漂校正过程中，采用对散射本底变化不灵敏的对称零面积法进行自动寻峰，并用标准方差进行指示峰判别。利用先验知识(上一次能量刻度)和高斯概率密度函数对当前指示峰进行定性分析，确定指示峰能量。将指示峰峰位和定性分析获得的能量值采用最小二乘法进行拟合，获得能量刻度系数，并对偏离较大的数据进行筛选，达到能量自动刻度目的，实现X射线荧光测井仪器谱谱漂校正。文章采用所述的谱漂校正方法对某次X射线测井仪温度实验的322条谱线进行校正，结果表明该方法能够有效地自动校正X射线荧光测井仪谱漂。

The Study of the Rescale Method of the Spectrum Shifting in X-Ray Fluorescence Well Logging

The X-ray fluorescence well logging technology is a significant method that can make quantitative analysis orsemi-quantitative analysis on the wellface .This method is very important to mineral exploration .The spectrum shifting is ofte n observed in the X-rayfluorescence well logging because the temperature in the well changes acutely .The hardware is used to release the spectrum shifting an d the software method is used to rescale the tiny spectrum shifting .There are too manyspectra to be rescaled in a well logging task by manually .In this pa per,an auto method to rescale spectrum shifting,via the expert system model which is based on the special process to rescale spectrum shifting in manual,is presented .The symmetric zero-area conversion method,which is not sensitive t o the changes of the baseline,is used to research the peaks .And then,the characteristic peaks will be identified by the standard errors,automatically .T he prior knowledge (the last energy scale) and the gauss probability density function are used to analyze the peaks qualitatively and confirm the energy of characteristic peaks .Then the least square method is applied energy calibration . The singular deviation point,away from the calibrationline,will be rejected and the energy ratio will be obtained again .This method is applied for rescalin g spectrum shifting in 322 spectra and obtains a satisfactory achievement .