Research And Experiment Of Scale Factors In Uranium Logging

Natural γ-ray spectrum logging is an advanced qualitative and quantitativeinterpretation method, which used to tell the nature of the rock and the content ofradioactive nuclide in the mineral, by studying of natural gamma ray spectrum.In this article, we are trying to form a new subdivision interpretation technology forenergy spectrum γ-ray logging, by introducing the subdivision interpretation methods ofγ-ray logging into the traditional energy spectrum analysis methods. The scale factors andthe characteristic parameter are two most important parameter in subdivisioninterpretation technology for energy spectrum γ-ray logging. In this article, we focus onthe method of finding scale factors.Referring to the calculating method of scale factor in the subdivision interpretationmethods of γ-ray logging and traditional natural γ-ray spectrum logging, we are trying tostudy the calculating method of the scale factor, and prove it by the analysis of actualmeasurement data.During our γ-ray spectrum logging test, HPGe detector and LaBr3detector wereused on standard model. The HPGe detector has a good performance of spectrumstabilization technology as well as perfect energy resolving power, so the characteristicpeaks could be divided accurately and much more characteristic peaks can be selected.As a result, We get a satisfactory result of actual measurement data, the relative errors ofexplain content for main element are under5percent. On one hand, it is feasible to getthe scale factors through standard model, on the other hand, the advantage of naturalγ-ray spectrum logging is proved also.Because it is the first time to use LaBr3detector in γ-ray spectrum logging, there aresome problems exist such as spectral shift. Through the analysis of feature of actualmeasurement data, we select some available data as well as the characteristic peaks. Theresults prove the feasibility of LaBr3detector in γ-ray spectrum logging, for the relativeerror of explain content for main element are under10percent.During the data analysis, the characteristic peaks were used for the radial energyunder1MeV, the contribution of compton effect were calculated also, a satisfactoryresult still arrived.Generally speaking, on standard model. the scale factor can be obtained bychoosing proper characteristic peaks according to the feature of actual measurement data,as well as the relative error of explain content can be very small.