The Element Enrichment Of Soil And Ore Prediction Of Xishanwanyangchang Silver Multi-metal Deposit In Inner Mongolia

Xishanwanyangchang silver deposit is located in the east of Langshan— Zha’ertaishan—Neoproterozoic-Mesoproterozoic rift zone in the northern margin of the North China Plate. The fault structure is relatively developed, and the geological conditions of the ore-forming are well in study area. The deposit is hosted in acidic volcano rock of the Lower Cretaceous Bainvyangpan Formation(K1bn), the roll rocks are mainly rhyolite、rhyolite porphyry and rhyolite breccia, rocks(ore) silicification, fluoritization, pyrite mineralization alteration, because suffer from magmatic activity and tectonic action.The data of soil geochemical elements indicates that the enrichment characteristics of Ag Sb、W、Au element are obvious in regional soil. The enrichment characteristics of Mo、Pb、Bi、As are low. Cu、Zn are deletion. Ag、Sb、W、Au elements are highly enriched in I、II、IV district, especially in the soil of Rhyolite, rhyolite、rhyolite porphyry and rhyolite breccia. This reflects that the original rock has good mineralization potential. Combined with previous work data of the research area, The mainly studies of soil geochemical exploration and ore prediction are in the II、IV district.The abnormal limit of the single element in the II、IV zone is calculated, and the abnormal chart of the single element is plotted, and the evaluation is carried out. The mapping and interpret of the single element anomaly map is based on the abnormal limit of single element. Frequency method and fractal method is used to calculate the anomaly threshold. By comparing the result of two methods and the enrichment degree of elements, the anomaly threshold of fractal method is more effective for main ore-forming elements Ag,so the anomaly threshold is determined by the frequency method.Use correlation analysis and factor analysis determine the symbiotic association of elements, and draw the anomaly picture of factor score. Factor scores anomaly is consistent with with the single element anomaly,which along the acidic volcanic rocks of Mazongshan fault extending NE is favorable target for silver deposit. Factor scores anomaly is better than the single element anomaly. Overall, using factor analysis showed that the abnormal distribution of relative concentration, concentration and zoning characteristics is more obvious, to better guide the prospecting.There is a prospecting area in each of Ⅱ zone and the Ⅳ zone, under the conditons of geological conditions, geochemical elements enrichment and abnormal characteristics of mine area. Y-1 forecast area in II zone along the acidic volcanic rocks of Mazongshan fault extending NE.The nested elements anomalies are mainly Ag, Sb, W, As, Au. Y-2 prediction area is located in the north of the Ⅳ zone, and extending NE. It main exposed rhyolite、rhyolite porphyry of the Lower Cretaceous Bainvyangpan Formation(K1bn), the enrichment characteristics of Ag、Sb、W elements are obviously in regional soil, The nested elements anomalies are mainly Ag, Cu, Sb, W, Pb, Bi, Au. the anomaly is remarkable and has good prospecting potential.