Anomaly-Background Separation and Geochemical Map Generation for Pb and Zn in Parkam District Based on U–Statistical Method, Kerman, Iran

Abstract

There are several statistical methodologies presented for separating anomalous values from background values leading to determination of anomalous areas. These methods range from simple approaches to complicated ones and include methods such as statistical parameters of distribution (as a nonstructural method), U-spatial statistic (as a structural method), partitioning method and etc. Structural methods take the sampling locations and their spatial relation into account for estimating the anomalous areas. The U-spatial statistic method is one of the most important structural methods.It considers the location of samples and carries out the statistical analysis of the data without judging from a geochemical point and tries to separate the subpopulations and also to determine anomalous areas. In present study, the surface samples from the Parkam exploration district were used in order to compare statistical parameters of distribution and U-statistic in separating anomalous values from background and providing the map of anomaly for grade values of Pb and Zn. Results suggest that the samples indicated by U-statistic method as anomalous are more regular and involve less dispersion compared to those indicated by the method of statistical parameters of distribution. Thus the map of promising areas for Pb and Zn in the exploration district has been prepared using the U-statistic method.