A method for metallogenic diagnosis based on coupling of prospecting-information contents and expert weight of evidence model

In the paper,taking the example of copper-polymetallic deposits,mineralization localization forecast was conducted in Dingxiang district of Shitai county in South Anhui province.After analyzing data from geology,geophysics,geochemistry,remote sensing and so on,seven prediction variables were used.To make full use of knowledge from the subjective and objective aspects,a method of metallogenic diagnosis was proposed;that is,forecast technique based on the coupling of prospecting-information contents and expert weight of evidence.Firstly,the objective weights were obtained according to information contents of variables which are computed by objective mineralization forecast method(prospecting-information contents).Secondly,the subjective weights were obtained according to knowledge from experts.Subsequently,synthetical weights were got on the basis of fusion of subjective and objective weights by D-S evidence theory.Finally,color block map of metallogenic favorability was made in the light of posterior probability of cells,which is computed by combining synthetical weights with expert weight of evidence.The forecasting result indicated that the model could effectively synthesize knowledge from the subjective and objective aspects and its result was more scientific and reasonable.Compared with prospecting-information contents and expert weight of evidence,it could obtain better forecasting result.