The giant Dahutang tungsten(W)deposit has a total reserve of more than 1.31 Mt WO3.Veinlet-disseminated scheelite and vein type wolframite mineralization are developed in this deposit,which are related to Late Mesozoi...The giant Dahutang tungsten(W)deposit has a total reserve of more than 1.31 Mt WO3.Veinlet-disseminated scheelite and vein type wolframite mineralization are developed in this deposit,which are related to Late Mesozoic biotite granite.Four major types of alterations,which include albitization,potassic-alteration,and greisenization,and overprinted silicification developed in contact zone.The mass balance calculate of the four alteration types were used to further understanding of the mineralization process.The fresh porphyritic biotite granite has high Nb,Ta,and W,but low Ca and Sr while the Jiuling granodiorite has high Ca and Sr,but low Nb,Ta,and W concentrations.The altered porphyritic biotite granite indicated that the Nb,Ta,and W were leached out from the fresh porphyritic biotite granite,especially by sodic alteration.The low Ca and Sr contents of the altered Neoproterozoic Jiuling granodiorite indicate that Ca and Sr had been leached out from the fresh granodiorite by the fluid from Mesozoic porphyritic biotite granites.The metal W of the Dahutang deposit was mainly derived from the fluid exsolution from the melt and alteration of W-bearing granites.This study of alteration presents a new hydrothermal circulation model to understand tungsten mineralization in the Dahutang deposit.展开更多
A combination of mineralogical and multielement analyses was used to characterize the hydrothermal alteration,pathfinder elements and their distribution within the gold deposits in North Mara mines,the Archean Musoma-...A combination of mineralogical and multielement analyses was used to characterize the hydrothermal alteration,pathfinder elements and their distribution within the gold deposits in North Mara mines,the Archean Musoma-Mara greenstone belt,Tanzania. The aim was to evaluate the suitability of alteration mineral assemblages and composition as an effective exploration marker for fingerprinting展开更多
基金This research is jointly funded by the Project of China Geological Survey(DD20190186 and 12120114034501)National Natural Science Foundation of China(42062006 and 41962007).
文摘The giant Dahutang tungsten(W)deposit has a total reserve of more than 1.31 Mt WO3.Veinlet-disseminated scheelite and vein type wolframite mineralization are developed in this deposit,which are related to Late Mesozoic biotite granite.Four major types of alterations,which include albitization,potassic-alteration,and greisenization,and overprinted silicification developed in contact zone.The mass balance calculate of the four alteration types were used to further understanding of the mineralization process.The fresh porphyritic biotite granite has high Nb,Ta,and W,but low Ca and Sr while the Jiuling granodiorite has high Ca and Sr,but low Nb,Ta,and W concentrations.The altered porphyritic biotite granite indicated that the Nb,Ta,and W were leached out from the fresh porphyritic biotite granite,especially by sodic alteration.The low Ca and Sr contents of the altered Neoproterozoic Jiuling granodiorite indicate that Ca and Sr had been leached out from the fresh granodiorite by the fluid from Mesozoic porphyritic biotite granites.The metal W of the Dahutang deposit was mainly derived from the fluid exsolution from the melt and alteration of W-bearing granites.This study of alteration presents a new hydrothermal circulation model to understand tungsten mineralization in the Dahutang deposit.
文摘A combination of mineralogical and multielement analyses was used to characterize the hydrothermal alteration,pathfinder elements and their distribution within the gold deposits in North Mara mines,the Archean Musoma-Mara greenstone belt,Tanzania. The aim was to evaluate the suitability of alteration mineral assemblages and composition as an effective exploration marker for fingerprinting
