The newly-discovered supergiant Huayangchuan uranium(U)-polymetallic(Sr,Se,REEs,Ba,Nb and Pb)deposit is located in the Qinling Orogen,central China.The deposit underwent multistage mineralization,with the main carbona...The newly-discovered supergiant Huayangchuan uranium(U)-polymetallic(Sr,Se,REEs,Ba,Nb and Pb)deposit is located in the Qinling Orogen,central China.The deposit underwent multistage mineralization,with the main carbonatite ore stage being the most important for the U,Nb,REE,Sr and Ba endowments.According to the mineral assemblages,the main carbonatite ore stage can be divided into three substages,i.e.,sulfate(Ba-Sr),alkali-rich U and REE-U mineralization.Main-stage titanite from the Huayangchuan igneous carbonatite are rich in high field strength elements(HFSEs,e.g.,Zr,Nb and REEs),and show clear elemental substitutions(e.g.,Ti vs.Nb+Fe+Al and Ca+Ti vs.Fe+Al+REE).High-precision LA-ICP-MS titanite dating yielded a U-Pb age of 209.0±2.9 Ma,which represents the mainstage mineralization age at Huayangchuan,and is coeval with the local carbonatite dyke intrusion.This mineralization age is further constrained by the Re-Os dating of molybdenite from the Huayangchuan carbonatite,which yielded a weighted mean age of 196.8±2.4 Ma.Molybdenite Re contents(337.55-392.75 ppm)and C-OSr-Nd-Pb isotopic evidence of the Huayangchuan carbonatite both suggest a mantle origin for the carbonatite.Our study supports that the Late Triassic carbonatite magmatism was responsible for the world-class U-Mo-REE mineralization in the Qinling Orogen,and that the regional magmatism and ore formation was likely caused by the closure of the Mianlue ocean and the subsequent North China-South China continent-continent collision.展开更多
The Huayangchuan ore belt is located in the western segment of Xiaoqinling Orogen in the southern margin of the North China Craton(NCC),and hosts voluminous magmatism and significant U-REE-Mo-Cu-Fe polymetallic minera...The Huayangchuan ore belt is located in the western segment of Xiaoqinling Orogen in the southern margin of the North China Craton(NCC),and hosts voluminous magmatism and significant U-REE-Mo-Cu-Fe polymetallic mineralization.However,geochronological framework of the various mineralization phases in this region is poorly understood.Here,we present new Re-Os isochron ages on magnetite from the Caotan Fe deposit(2 675 ± 410 Ma,MSWD = 0.55),and on pyrite from the Jialu REE deposit(2 127 ± 280 Ma,MSWD = 1.9) and Yuejiawa Cu deposit(418 ± 23 Ma,MSWD =11.5),and Re-Os weighted average model age on pyrite from the Taoyuan Mo-U deposit(235 ± 14 Ma,MSWD = 0.17).These ages,combined with regional geology and mineralization ages from other deposits,suggest that mineralization in the Huayangchuan ore belt lasted from the Neoarchean to the Late Mesozoic.The mineralization corresponds to regional tectono-magmatic events,including the Neoarchean alkali magmatism(REE mineralization),Paleoproterozoic plagioclase-amphibolite emplacement(Fe mineralization),Paleoproterozoic pegmatite magmatism(U mineralization),Paleozoic Shangdan oceanic slab subduction-related arc magmatism(Cu mineralization),Early Mesozoic Paleo-Tethys Ocean subduction-related arc magmatism(Mo-U mineralization),and Late Mesozoic Paleo-Pacific oceanic plate subduction direction change-related Mo(-Pb) mineralization.We proposed that the Huayangchuan ore belt has undergone prolonged metallogenic evolution,and the magmatism and associated mineralization were controlled by regional geodynamic events.展开更多
基金supported by the Type-B Strategic Pilot Science and Special Technology Program,Chinese Academy of Sciences(XDB18030206)Academician Workstation of Sino Shaanxi Nuclear Industry Group(ZSH-YS180101 and YS190101)。
文摘The newly-discovered supergiant Huayangchuan uranium(U)-polymetallic(Sr,Se,REEs,Ba,Nb and Pb)deposit is located in the Qinling Orogen,central China.The deposit underwent multistage mineralization,with the main carbonatite ore stage being the most important for the U,Nb,REE,Sr and Ba endowments.According to the mineral assemblages,the main carbonatite ore stage can be divided into three substages,i.e.,sulfate(Ba-Sr),alkali-rich U and REE-U mineralization.Main-stage titanite from the Huayangchuan igneous carbonatite are rich in high field strength elements(HFSEs,e.g.,Zr,Nb and REEs),and show clear elemental substitutions(e.g.,Ti vs.Nb+Fe+Al and Ca+Ti vs.Fe+Al+REE).High-precision LA-ICP-MS titanite dating yielded a U-Pb age of 209.0±2.9 Ma,which represents the mainstage mineralization age at Huayangchuan,and is coeval with the local carbonatite dyke intrusion.This mineralization age is further constrained by the Re-Os dating of molybdenite from the Huayangchuan carbonatite,which yielded a weighted mean age of 196.8±2.4 Ma.Molybdenite Re contents(337.55-392.75 ppm)and C-OSr-Nd-Pb isotopic evidence of the Huayangchuan carbonatite both suggest a mantle origin for the carbonatite.Our study supports that the Late Triassic carbonatite magmatism was responsible for the world-class U-Mo-REE mineralization in the Qinling Orogen,and that the regional magmatism and ore formation was likely caused by the closure of the Mianlue ocean and the subsequent North China-South China continent-continent collision.
基金financially supported by the Academician Workstation of Sino Shaanxi Nuclear Industry Group(Nos.ZSH-YS190101 and ZSH-YS180101)Major Project of Basic and Applied Basic Research in Guangdong Province(No.2019B030302013)。
文摘The Huayangchuan ore belt is located in the western segment of Xiaoqinling Orogen in the southern margin of the North China Craton(NCC),and hosts voluminous magmatism and significant U-REE-Mo-Cu-Fe polymetallic mineralization.However,geochronological framework of the various mineralization phases in this region is poorly understood.Here,we present new Re-Os isochron ages on magnetite from the Caotan Fe deposit(2 675 ± 410 Ma,MSWD = 0.55),and on pyrite from the Jialu REE deposit(2 127 ± 280 Ma,MSWD = 1.9) and Yuejiawa Cu deposit(418 ± 23 Ma,MSWD =11.5),and Re-Os weighted average model age on pyrite from the Taoyuan Mo-U deposit(235 ± 14 Ma,MSWD = 0.17).These ages,combined with regional geology and mineralization ages from other deposits,suggest that mineralization in the Huayangchuan ore belt lasted from the Neoarchean to the Late Mesozoic.The mineralization corresponds to regional tectono-magmatic events,including the Neoarchean alkali magmatism(REE mineralization),Paleoproterozoic plagioclase-amphibolite emplacement(Fe mineralization),Paleoproterozoic pegmatite magmatism(U mineralization),Paleozoic Shangdan oceanic slab subduction-related arc magmatism(Cu mineralization),Early Mesozoic Paleo-Tethys Ocean subduction-related arc magmatism(Mo-U mineralization),and Late Mesozoic Paleo-Pacific oceanic plate subduction direction change-related Mo(-Pb) mineralization.We proposed that the Huayangchuan ore belt has undergone prolonged metallogenic evolution,and the magmatism and associated mineralization were controlled by regional geodynamic events.