Study On The Geochemical Data Processing Method And Mineral Resource Targeting In Ganjia Area In Xiahe County Of Gansu

Geochemical data processing as one the most basic and important problems in geochemical work,and it decide success or fail.By processing the geochemical data,geochemical workers study the elements of the symbiotic combination pattern and spatial distribution,to determine the background value,abnormal division and evaluation of anomalies.The traditional statistical methods accord with normal distribution or log normal distribution in geochemical data as the premise,establish data processing model using statistical features of the data, the other is to establish the mathematical model considering the distribution characteristics of elements of the space(this article using the method of universal Kriging trend surface,average smoothing filtering method).The article takes the Geochemical exploration data in Ganjia area in Xiahe County of Gansu as an example,using correlation analysis,cluster analysis, factor analysis of the elements are divided, and the zoning series:Hg-(Ag、As、Au、Sb、Pb)-(Zn、Ni、Ti、Cu)-(Mo、W).Using traditional statistical methods, universal Kriging trend surface,average smoothing filtering method to deal with geochemical exploration data concluded that as the large area,large samples,batch sampling, sampling time and different labs,regional geochemical data should be leveled; traditional statistical method should be maximize the former provided: the distribution of elements in geological body accord with normal distribution or log normal distribution,otherwise,simply add n times standard deviation to the mean and determine the anomaly threshold,the anomaly threshold value is far away the true value;average smooth filtering method identify much weak anomaly that contain many known deposits and occurrences in study area,but most of the abnormal area is small, not a film distribution.Besides,in order to select a suitable window size, a lot of experiments are necessary;universal Kriging trend method identify much weak anomaly that contain many almost all known deposits and occurrences in study area and the abnormal have large scale,high anomaly intensity and good identity of concentration centres.Besides,the abnormal area along with NW-SE direction as well as the reflects in study area.Besides,universal Kriging trend method identify some abnormal areas that do not found by the other methods,which is important to the next word.So,the universal Krigingtrend method is the most suitable method to determine geochemical anomaly thresholds in the region.By studying the strata, structures and intrusive rocks,deposits, geochemical anomaly and so on, the symbol in the study area is: the NW-NE fracture +intermediate-acidic intrusive rocks and carbonate +Au-Ag-As-Sb-(Cu) geochemical anomaly.According to the symbol,four important for prospecting target areas that have a good prospecting potential are been delineated.