The Liaoji Proterozoic rift is an inter-intracontinenatl rift developed from Archean granite-greenstone tectonic regime and contains many important mineral deposits of U, B, magnesite, Pb-Zn, Au, Ag, Co and P. These d...The Liaoji Proterozoic rift is an inter-intracontinenatl rift developed from Archean granite-greenstone tectonic regime and contains many important mineral deposits of U, B, magnesite, Pb-Zn, Au, Ag, Co and P. These deposits were formed as the result of late mobilization, transportation and concentfation of the previously enriched ore-forming mate- rials in several ore-bearing formations formed during the rift stage. So the metallogeny of these deposits in the rift shows both inheritance and new generation of the ore-forming materials. In future ore-searching practice, attentions should be paid on the studies of the ore-bearing formations in the rift, on the multiple stages of metallogeny and and on multiple derivations of the ore-forming materials.展开更多
The Habo alkaline intrusion, which is located in the south of the Sanjiang area, Yunnan Province, China, is a typical Cenozoic alkaline intrusion. There are a series of small to medium-sized Au and Pb-（Zn） deposits ...The Habo alkaline intrusion, which is located in the south of the Sanjiang area, Yunnan Province, China, is a typical Cenozoic alkaline intrusion. There are a series of small to medium-sized Au and Pb-（Zn） deposits around this intrusion. Those deposits are spatially associated with the Habo alkaline intrusion. （1） The δ^34S values of sulfides from Au deposits range from -1.91‰ to 2.69 ‰, which are similar to those of Pb-（Zn） deposits （-3.82 ‰ to -0.05 ‰） and both indicate a much greater contribution from magma. （2） The Habo alkaline intrusion has relatively homogeneous Pb isotopic compositions with ^206pb/^204pb ranging from 18.608 to 18.761, ^207pb/^204pb from 15.572 to 15.722 and ^20spb/^204pb from 38.599 to 39.110. These Pb isotope ratios are similar to those of Au deposits, whose ^206pb/^204pb range from 18.564 to 18.734, ^20Tpb/^20apb from 15.582 to 15.738 and ^208pb/^204pb from 38.592 to 39.319. Pb ratios in both the intrusion and Au deposits suggest that Pb mainly derived from the depth, probably represents a mixture of mantle and crust. Pb-（Zn） deposits, however, show a decentralized trait, and most of them are similar to that of the alkaline intrusion with ^206pb/^204pb ranging from 18.523 to 18.648, ^207pb/^204pb from 15.599 to 15.802, and ^20spb/^204pb from 38.659 to 39.206. （3） In the plumbotectonic diagram ^20Tpb/^204pb versus ^206pb/^204pb, almost all of Au and Pb-（Zn） deposits have the same projection area with the Habo alkaline intrusion, which indicates that those deposits almost share the same source with the alkaline intrusion. （4） Isotopic age of the Habo alkaline intrusion is 36-33 Ma, which is similar to that of Beiya, whose ore- related alkaline porphyries age is 38-31 Ma and molybdenite Re-Os age is 36.9 Ma. Therefore, along with S-Pb isotope traits, we suggest that the Habo Au and Pb-（Zn） deposits should be typically Ailaoshan-Red RiverCenozoicalkaline-related deposits and ore-forming ages of these deposits should be later than that of the Habo alkaline intrusion.展开更多
1 Outline of the Yangtze terrain THE northwestern area of Sichuan and the joined area of Yunnan, Guizhou and Guangxi are the two majorfields where lots of Carlin-type Au ore deposits are located. Both of them belong t...1 Outline of the Yangtze terrain THE northwestern area of Sichuan and the joined area of Yunnan, Guizhou and Guangxi are the two majorfields where lots of Carlin-type Au ore deposits are located. Both of them belong to the western area ofYangtze terrain. The evolution of Yangtze terrain affected profoundly the geological evolution in these areas. Many epithermal ore deposits, such as Carlin-type gold, lead, zinc, mercury, stibium and arsenic,occur in the these areas, due to the evolution of crust in Yangtze terrain. The foundation of Yangtze terrain shows a structure of three stories, mainly composed of the Proterozoic clastic rocks and carbonic rocks that were involved in low-middle grade metamorphose. The meaningof the Yangtze terrain changed according to several geological times, which can be said that the activity ofYangtze terrain changed in the past. The Yangtze terrain undertook several processes of landmass hyper-展开更多
Mapping with Ag/Au ratios of mineralized rocks and ores as a parameter reveals that the deep fractures in the Gangdise block control the distribution of the high value regions which may represent the shallow zones of ...Mapping with Ag/Au ratios of mineralized rocks and ores as a parameter reveals that the deep fractures in the Gangdise block control the distribution of the high value regions which may represent the shallow zones of strongly mineralized areas. The variance gradient regions with large Ag/Au ratio may represent the boundaries between strongly mineralized areas and weakly mineralized areas. In the middle part of the Gangdise block, gold and silver mineralization centers mainly distribute along the NW extending Coqen-Xigaze region, NE extending Yangbajain region and E-W extending Lhasa-Gongbogyamda region. The gold and silver mineralized rocks and ores may have been slightly denuded in the west of the middle Gangdise block, and the denudation in the east, however, may be stronger. The primary gold and silver prospect in the west may be better than in the east.展开更多
文摘The Liaoji Proterozoic rift is an inter-intracontinenatl rift developed from Archean granite-greenstone tectonic regime and contains many important mineral deposits of U, B, magnesite, Pb-Zn, Au, Ag, Co and P. These deposits were formed as the result of late mobilization, transportation and concentfation of the previously enriched ore-forming mate- rials in several ore-bearing formations formed during the rift stage. So the metallogeny of these deposits in the rift shows both inheritance and new generation of the ore-forming materials. In future ore-searching practice, attentions should be paid on the studies of the ore-bearing formations in the rift, on the multiple stages of metallogeny and and on multiple derivations of the ore-forming materials.
文摘The Habo alkaline intrusion, which is located in the south of the Sanjiang area, Yunnan Province, China, is a typical Cenozoic alkaline intrusion. There are a series of small to medium-sized Au and Pb-（Zn） deposits around this intrusion. Those deposits are spatially associated with the Habo alkaline intrusion. （1） The δ^34S values of sulfides from Au deposits range from -1.91‰ to 2.69 ‰, which are similar to those of Pb-（Zn） deposits （-3.82 ‰ to -0.05 ‰） and both indicate a much greater contribution from magma. （2） The Habo alkaline intrusion has relatively homogeneous Pb isotopic compositions with ^206pb/^204pb ranging from 18.608 to 18.761, ^207pb/^204pb from 15.572 to 15.722 and ^20spb/^204pb from 38.599 to 39.110. These Pb isotope ratios are similar to those of Au deposits, whose ^206pb/^204pb range from 18.564 to 18.734, ^20Tpb/^20apb from 15.582 to 15.738 and ^208pb/^204pb from 38.592 to 39.319. Pb ratios in both the intrusion and Au deposits suggest that Pb mainly derived from the depth, probably represents a mixture of mantle and crust. Pb-（Zn） deposits, however, show a decentralized trait, and most of them are similar to that of the alkaline intrusion with ^206pb/^204pb ranging from 18.523 to 18.648, ^207pb/^204pb from 15.599 to 15.802, and ^20spb/^204pb from 38.659 to 39.206. （3） In the plumbotectonic diagram ^20Tpb/^204pb versus ^206pb/^204pb, almost all of Au and Pb-（Zn） deposits have the same projection area with the Habo alkaline intrusion, which indicates that those deposits almost share the same source with the alkaline intrusion. （4） Isotopic age of the Habo alkaline intrusion is 36-33 Ma, which is similar to that of Beiya, whose ore- related alkaline porphyries age is 38-31 Ma and molybdenite Re-Os age is 36.9 Ma. Therefore, along with S-Pb isotope traits, we suggest that the Habo Au and Pb-（Zn） deposits should be typically Ailaoshan-Red RiverCenozoicalkaline-related deposits and ore-forming ages of these deposits should be later than that of the Habo alkaline intrusion.
文摘1 Outline of the Yangtze terrain THE northwestern area of Sichuan and the joined area of Yunnan, Guizhou and Guangxi are the two majorfields where lots of Carlin-type Au ore deposits are located. Both of them belong to the western area ofYangtze terrain. The evolution of Yangtze terrain affected profoundly the geological evolution in these areas. Many epithermal ore deposits, such as Carlin-type gold, lead, zinc, mercury, stibium and arsenic,occur in the these areas, due to the evolution of crust in Yangtze terrain. The foundation of Yangtze terrain shows a structure of three stories, mainly composed of the Proterozoic clastic rocks and carbonic rocks that were involved in low-middle grade metamorphose. The meaningof the Yangtze terrain changed according to several geological times, which can be said that the activity ofYangtze terrain changed in the past. The Yangtze terrain undertook several processes of landmass hyper-
基金the National Key Project for Basic Research (G1998040800), the National Natural Science Foundation of China (Grant Nos. 49873013, 40073012) and China Geological Survey (20001020223023).
文摘Mapping with Ag/Au ratios of mineralized rocks and ores as a parameter reveals that the deep fractures in the Gangdise block control the distribution of the high value regions which may represent the shallow zones of strongly mineralized areas. The variance gradient regions with large Ag/Au ratio may represent the boundaries between strongly mineralized areas and weakly mineralized areas. In the middle part of the Gangdise block, gold and silver mineralization centers mainly distribute along the NW extending Coqen-Xigaze region, NE extending Yangbajain region and E-W extending Lhasa-Gongbogyamda region. The gold and silver mineralized rocks and ores may have been slightly denuded in the west of the middle Gangdise block, and the denudation in the east, however, may be stronger. The primary gold and silver prospect in the west may be better than in the east.
