The Geochemical Anomalies Data Processing Of1:50000in Chongqing Wenfeng Distric

The core of the exploration geochemistry is delineating the geochemicalbackground and geochemical anomalies.The different processing method directlycontrols whether we can correctly extract the prospecting information and improve theeffect of geochemical prospecting.This paper combined with1:50000stream sedimentgeochemical anomaly information data of Chongqing Wenfeng district, comparisonand analysis with different processing method, summarizing the method ofdetermining the abnormal threshold for the region, and then delineating the abnormal,making metallogenic prospect forecast.The conventional statistical method of Geochemical exploration data processingdemand the data obeyingnormal distributed or logarithmic normal distribution,otherwise we need to Removethe high data and low data; while85%frequencystatistics rule of data without any requirements; we can use fractal method to processthe data which has more discrete data, the shortage of this method is morecomplicated; Trend surface method can make use of Surfer software for dataprocessing, in order to avoid affecting the form of trend surface,we need to preprocessthe data by replacing the observed value which higher than the critical value with totalcumulative frequency of95%of the critical value,This thesis mainly comparativeanalysisthe conventional statistical method and trend surface method.Making correlation analysis, cluster analysis and factor analysis for the areaelement, the main metal elements in this area can be divided into three groups,Cr-Fe-Mn-V-F-Ni-Zn-Ag; Ba-As-Sb-Pb-Hg-Bi-Mo-Au and Cu-Cd-Mo-Au. Then wecan get the combination anomalies map, comprehensive anomalies map, abnormalanatomy map of19elements.There are13kinds of abnormal areas by using the statistical methods, Thestrength of abnormal is generally, smaller,sporadic distribution;By using the trend surface method,we get16kinds of abnormal areas.These areas are relativelyconcentrated; The abnormal has moderate strength,bettersuperimposed and larger size.Both of the two methods are also get5kinds of3B anomalies. They get severalanomaliesat the mineralized spots which has been found in the previous,the majorexposure stratums are the Triassic daye group and badong group.Overall,comprehensive anomalies map,worked out by the trend surface method,canbetter cover the previous point of mineralization. So the trend surface method isadopted to draw the exceptions to delineating metallogenic prospective map.By Comprehensive studyingthe mineralization vista areas and ore-forminggeological characteristics,we can get that the metallogenic geological conditions ofdistrict is general,themain Ore-forming elements of mineralization vista areas are Cu、Pb、Zn polymetallic, Inthe metallogenic prospects area,there will be one Ⅱ levelsmetallogenic prospective area and three Ⅲ levels metallogenic prospect areas.