| Thesis topics is from the National High Technology Research and DevelopmentProgram (863Program) Resources in the field of environmental technology IssuePrecision spectroscopy detection equipment R&D (No:2012AA061803) and theChina Geological Survey Bureau Project "the New Technology Study of AirborneGeophysical Anomaly Quick Verification "(No:1212011120186). During mineralexploration, traditional geochemical anomaly inspection must to be through "in-situsampling-Transportation-sample processing-Chemical analysis-reported theresults" a series of processes, it takes a long period to get the results of geochemicaldata,besides the results of geochemical anomaly data would not be obtained intime,even the weak anomalies would go missing and the fake anomalies would comeup. while the in-situ X-ray fluorescence measurements can simplify conventionalgeochemical workflow, enable real-time measurement and analysis of field samples,data processing, in-situ delineation of geochemical anomalies, abnormal laboratoryverification, etc，Anomaly verification must be completed in the laboratory in the past,that improves the efficiency of field geological work.However,field samplingenvironment is often severe,and the fluorescence analyzer is a precisioninstrument,which could be impacted by temperature, humidity and otherenvironmental impacts, this contradiction led spot X-ray fluorescence data quality notas good as results of high quality data from a stable laboratory conditions usingchemical methods.1, there are some flaws in the traditional statistical methods for extracting XRFmeasurement anomalies, the main reason is the traditional method based on the theoryassuming various elements in the earth’s crust are normally distributed.Geostatisticalresearch and practice have shown that certain target elements in geological bodies ofcontent is not normally distributed, and the XRF data itself is vulnerable to externalenvironmental interference constraints of this situation, data quality is not as accurateas laboratory analytical chemical methods.that led the geochemical anomaliesresulting lower limit calculation erroneous, which eventually led geochemicalanomaly identification errors;2, the second-order multifractal anomalies calculated lower limit is generally low, thereason is that the measurement data by XRF field measurement conditions, statisticalfluctuations increase, the data structure is relatively discrete scaling region boundariesare not obvious, extracted anomalous points are too much, resulting in anomalous too wide,as a result solely useing the he second-order multifractal method is notsignificative.3, Since the data is fit into multiple scaling region to correspond in the multi-stagefractal, part of the second-order fractal measurement points identified as anomalyvalues processed as high background,that is more in line with the anomaly valuesproportion in the actual work of exploration geochemistry;4, in the fast Fourier fractal filtering method, since the background value is dynamicin region Background extraction,the data including the errors caused by differentgeological backgrounds,can extract the weak anomaly in the low background areas；The advantage of local background extraction is that they can be directly used，without any processing of the original data，but with a smaller anomaly extractionrange and lower concentrated tendency.that proved the anomaly extraction methodsensitivity is not good as sensitivity of regional background method,and anomalyextraction method can be used as a kind of anomaly verification method.5, the wavelet method is more emphasis on the frequency character of XRFmeasurement data.since considered to be instrumentation and measurement noisecaused by statistical fluctuations，the high frequency signal decomposed at differentscales were excluded. that would help in the differentiating of geological fakeanomaly. But currently wavelet decomposition series only by experience.TheReasonably quantified decomposition designation needs in-depth research. |
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