Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to...Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to Muli ,Sichuan ,with a width of 5～35km .The junction is located in the arcuate turning part of the Alpine—Himalayan—Indosinian Tethyan tectonic domain ,which lies in the structural transition position between the Yangtze plate and the Yidun area . The plate junction represents an important tectonic belt ,which is a composed of a gold mineralization belt in the east Tethyan tectonic domain.(1) Garze—Litang plate junction may be divided into the following structural units:ductile shear zone and fracture system, Paleozoic nappes ,ophiolite \|tectonic blocks,flysch formation in passive continental margin (Triassic Xikang group ),forearc sedimentary formation in active margin (Triassic Yidun group),and such boundary geological bodies as granitoids ,faulted basins and Tertiary nappes.展开更多
The Qinling Carlin-type gold deposit belt is the second largest Carlin-type gold ore concentrated area in the world and occurs in Mesozoic intracontinental collisional orogen, contrasting to the Carlin-type gold depos...The Qinling Carlin-type gold deposit belt is the second largest Carlin-type gold ore concentrated area in the world and occurs in Mesozoic intracontinental collisional orogen, contrasting to the Carlin-type gold deposits in the Basin and Range province in Cenozoic active continental margin of West America. With ore-forming ages focussed at the range of 197.45-129.45 Ma, its metallogenic geodynamic background was the decornpression-pyrogenation regime at the transition stage from collisional compression to extension, indicating that gold mineralization synchronized with the Mesozoic continental collision. Geochemical studies discover that ore fluids and materials mainly came from the Hercynian-lndosinian tectonic layer. Mesozoic intracontinental subduction of Hercynian-lndosinian association along the Shuanghe-Gongguan fault led to the formation of Jinlongshan-Qiuling gold deposits. Accordingly, the tectonic metallogenic model is established for Qinling-pattern Carlin-type gold deposits.展开更多
The geotectonic setting refers to the three-dimensional space and relatedevents based on which a metallogenic system is formed and an ore-forming process takes place. Thispaper discusses the tectonic evolution of the ...The geotectonic setting refers to the three-dimensional space and relatedevents based on which a metallogenic system is formed and an ore-forming process takes place. Thispaper discusses the tectonic evolution of the southwestern margin of the North China paleocontinentand related geotectonic settings in which large or superlarge deposits are formed. Emphasis is puton the geodynamic conditions of the Jinchuan nickel-copper deposit, the Baiyin copper-polymetallicdeposit and the Hanshan gold deposit. It is significant that the three deposits occur together as a'trinity' on the same paleocontinental margin. The Jinchuan nickel-copper deposit was formed duringthe early stage of rifting of the paleocontinental margin; the Baiyin copper-polymetallic depositwas formed during the splitting stage of a continental-margin arc. The continental-margin arcspitting resulted in an 'island arc rift' in the early stage of evolution. The Hanshan gold depositwas formed within the Altun sinistral strike-slip fault system and its provenance is the'intraoceanic arc' volcanic rocks.展开更多
文摘Garez—Litang plate junction lies in the eastern margin of the Nujiang—Lancangjiang—Jinshajiang area, NW\|trendingly and antisigmoidally extending for more than 800km from Zhidoi ,Qinghai through Garze and Litang to Muli ,Sichuan ,with a width of 5～35km .The junction is located in the arcuate turning part of the Alpine—Himalayan—Indosinian Tethyan tectonic domain ,which lies in the structural transition position between the Yangtze plate and the Yidun area . The plate junction represents an important tectonic belt ,which is a composed of a gold mineralization belt in the east Tethyan tectonic domain.(1) Garze—Litang plate junction may be divided into the following structural units:ductile shear zone and fracture system, Paleozoic nappes ,ophiolite \|tectonic blocks,flysch formation in passive continental margin (Triassic Xikang group ),forearc sedimentary formation in active margin (Triassic Yidun group),and such boundary geological bodies as granitoids ,faulted basins and Tertiary nappes.
文摘The Qinling Carlin-type gold deposit belt is the second largest Carlin-type gold ore concentrated area in the world and occurs in Mesozoic intracontinental collisional orogen, contrasting to the Carlin-type gold deposits in the Basin and Range province in Cenozoic active continental margin of West America. With ore-forming ages focussed at the range of 197.45-129.45 Ma, its metallogenic geodynamic background was the decornpression-pyrogenation regime at the transition stage from collisional compression to extension, indicating that gold mineralization synchronized with the Mesozoic continental collision. Geochemical studies discover that ore fluids and materials mainly came from the Hercynian-lndosinian tectonic layer. Mesozoic intracontinental subduction of Hercynian-lndosinian association along the Shuanghe-Gongguan fault led to the formation of Jinlongshan-Qiuling gold deposits. Accordingly, the tectonic metallogenic model is established for Qinling-pattern Carlin-type gold deposits.
文摘The geotectonic setting refers to the three-dimensional space and relatedevents based on which a metallogenic system is formed and an ore-forming process takes place. Thispaper discusses the tectonic evolution of the southwestern margin of the North China paleocontinentand related geotectonic settings in which large or superlarge deposits are formed. Emphasis is puton the geodynamic conditions of the Jinchuan nickel-copper deposit, the Baiyin copper-polymetallicdeposit and the Hanshan gold deposit. It is significant that the three deposits occur together as a'trinity' on the same paleocontinental margin. The Jinchuan nickel-copper deposit was formed duringthe early stage of rifting of the paleocontinental margin; the Baiyin copper-polymetallic depositwas formed during the splitting stage of a continental-margin arc. The continental-margin arcspitting resulted in an 'island arc rift' in the early stage of evolution. The Hanshan gold depositwas formed within the Altun sinistral strike-slip fault system and its provenance is the'intraoceanic arc' volcanic rocks.
