The Study Of Geochemical Anomaly Structure For Wunugetushan Porphyry Cu-mo Deposit

The object of this research was to investigate the geochemical anomaly structure of porphyry copper-molybdenum deposit. The study mainly conducted at Wunugetushan deposit area, based on the two exploration profiles and four drill data collected, combined with investigation of the alternation zones and the mineralization characteristics. It was found that:(1)the obvious depletion in the borehole samples for CaO, MgO and Na20 compared with their own crust abundance respectively; (2) The enrichment for the ore-forming elements, such as Cu and Mo; (3)its all remain in the surface rocks of the deposits. The relationship of the information of depletion and enrichment in borehole surface rock samples was investigated for about 47 elements. It was also found that the depletion and enrichment phenomenon also occurred for other trace elements. In order to discuss the connection of the phenomenon with the orebody location and the alternation zones, the elements are divided into two sorts, depletion and enrichment, based on the lithology and its distribution information. This classification and its geological significances were also discussed.In order to find the rules of the elements depletion and enrichment phenomenon in the surficiall samples and its distribution characteristics, the basis to determination the geochemical investigation method, the surficial rock, debris and soil samples were also systematically investigated. The results showed that the depletion and enrichment phenomenon also been reflected to varying degrees and the significant distribution laws also was found. The study initially determined the proper sampling media and also the geochemical exploration indexes that could reflect the ore deposits location and the alternation degree.According to the elements spatial distributions and its relationship between the different sample medium, the vertical structure model of the geochemical anomaly in the borehole samples and the structure model in the surgical sample medium for Wunugetushan deposit was summarized. Finally, the overall geochemical anomaly structure model was constructed based on the positive and negative anomaly occurred in the borehole and surface samples.The geochemical anomaly structure models developed in this study can be applied to the investigation of the characteristics of the geochemical anomaly and to the deposit prospecting. The study also provides a successful case for the porphyry copper-molybdenum geochemical exploration in the future.