The Wuchuan-Sihui-Shaoguan(WSS)exhalative sedimentary pyrite belt in the southwestern part of the Qinzhou-Hangzhou(Qin-Hang)belt is the most important sulfur industry base in China.However,a wide range of metallogenet...The Wuchuan-Sihui-Shaoguan(WSS)exhalative sedimentary pyrite belt in the southwestern part of the Qinzhou-Hangzhou(Qin-Hang)belt is the most important sulfur industry base in China.However,a wide range of metallogenetic ages spanning from Ediacaran to Devonian has been reported in the literature.This age range does not support the idea that the typical character of"coeval mineralization"in an exhalative sedimentary mineralization belt in China and worldwide.Therefore,the precise determination of mineralization ages of representative deposits is necessary to provide guides for exploration and metallogenetic models.The Dajiangping pyrite deposit is a typical example of this kind of deposits and is also the largest deposit with a proven reserve of 210 Mt.This deposit was thought to have formed in Ediacaran or Devonian.In this study,2-3 layers of 10-25 cm thick 2M1-type microcrystalline muscovite slate abruptly embedded in the No.Ⅳmassive orebody of the deposit has been identified to be low-grade metamorphic K-bentonite.A Concordia zircon LA-ICP-MS U-Pb age of 432.5±1.3 Ma(mean standard weighted deviation of concordance and equivalence=1.2;N=11)has been yielded for the low-grade metamorphic K-bentonite.This age is distinctly different from the Rb-Sr isochron age of630.1±7.3 Ma for siliceous rock at the top of the No.Ⅲbanded orebody and the Re-Os isochron age of 389±62 Ma for pyrites from a laminated orebody.Instead,it is close to the intercept age(429 Ma)of the youngest detrital zircons from sandstone interlayers of the No.Ⅲbanded orebody.The Concordia age is also coincident with those of the Late Caledonian(400-460 Ma)magmatism-metamorphism events which are widely distributed in Cathaysia Block.Particularly,it agrees well with that of the Early Silurian extensional volcanism(434-444 Ma)which have been revealed in the Dabaoshan,Siqian-Hekou,and Nanjing volcanic basins in northern Guangdong Province and southern Jiangxi Province.Hence,the dating result in this study confirms that the sedimentary time of the ore-host Daganshan Formation is Early Silurian,and implies that the mineralization age of the Dajiangping pyrite deposit should also be Early Silurian.In combination with the Early Silurian age of Shezui pyrite deposit and the Dabaoshan volcanic basin along the WSS pyrite belt,it could be inferred that the WSS pyrite belt provides a record of the northern expanding of Qinzhou-Fangcheng trough in Early Silurian and that the exhalative pyrite mineralization was triggered by the postcollisional extension of the margin of Cathaysia Block after the intracontinental collision between Cathaysia Block and Yangtze Block during Late Caledonian stage.展开更多
Wuchuan Gelao and Miao Autonomous County is located in the northeast of Guizhou Province,and in the border of Guizhou and Chongqing,having a subtropical humid monsoon climate. There is no severe heat in summer,and no ...Wuchuan Gelao and Miao Autonomous County is located in the northeast of Guizhou Province,and in the border of Guizhou and Chongqing,having a subtropical humid monsoon climate. There is no severe heat in summer,and no severe cold in winter. It has distinct national characteristics,and there are many biological resources with national characteristics. A systematic investigation of biological resources in the county for nearly a month was carried out by organizing a professional investigation team. The investigation covered 5 townships and we visited 12 village committees and 26 villagers' groups,involving three ethnic groups: Gelao,Tujia and Miao. The biological resources closely related to the agricultural production and life of local ethnic groups were investigated,collected and sorted out. A total of 230 samples of all kinds of resources were collected,including 47 food crops,75 vegetables and annual crops,37 fruit trees and perennial crops,and 71 medicinal plants. Of these,a total of 73 were unique,superior and special resources. Based on general investigation and professional investigation,this paper analyzes the present situation,growth and decline of local agricultural biological resources,and puts forward some suggestions for the protection,development and utilization of agricultural biological resources.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.41873058 and 41462001)the Natural Science and Technology Foundation of Guizhou Province,China(Grant No.JZ[2015]2009)。
文摘The Wuchuan-Sihui-Shaoguan(WSS)exhalative sedimentary pyrite belt in the southwestern part of the Qinzhou-Hangzhou(Qin-Hang)belt is the most important sulfur industry base in China.However,a wide range of metallogenetic ages spanning from Ediacaran to Devonian has been reported in the literature.This age range does not support the idea that the typical character of"coeval mineralization"in an exhalative sedimentary mineralization belt in China and worldwide.Therefore,the precise determination of mineralization ages of representative deposits is necessary to provide guides for exploration and metallogenetic models.The Dajiangping pyrite deposit is a typical example of this kind of deposits and is also the largest deposit with a proven reserve of 210 Mt.This deposit was thought to have formed in Ediacaran or Devonian.In this study,2-3 layers of 10-25 cm thick 2M1-type microcrystalline muscovite slate abruptly embedded in the No.Ⅳmassive orebody of the deposit has been identified to be low-grade metamorphic K-bentonite.A Concordia zircon LA-ICP-MS U-Pb age of 432.5±1.3 Ma(mean standard weighted deviation of concordance and equivalence=1.2;N=11)has been yielded for the low-grade metamorphic K-bentonite.This age is distinctly different from the Rb-Sr isochron age of630.1±7.3 Ma for siliceous rock at the top of the No.Ⅲbanded orebody and the Re-Os isochron age of 389±62 Ma for pyrites from a laminated orebody.Instead,it is close to the intercept age(429 Ma)of the youngest detrital zircons from sandstone interlayers of the No.Ⅲbanded orebody.The Concordia age is also coincident with those of the Late Caledonian(400-460 Ma)magmatism-metamorphism events which are widely distributed in Cathaysia Block.Particularly,it agrees well with that of the Early Silurian extensional volcanism(434-444 Ma)which have been revealed in the Dabaoshan,Siqian-Hekou,and Nanjing volcanic basins in northern Guangdong Province and southern Jiangxi Province.Hence,the dating result in this study confirms that the sedimentary time of the ore-host Daganshan Formation is Early Silurian,and implies that the mineralization age of the Dajiangping pyrite deposit should also be Early Silurian.In combination with the Early Silurian age of Shezui pyrite deposit and the Dabaoshan volcanic basin along the WSS pyrite belt,it could be inferred that the WSS pyrite belt provides a record of the northern expanding of Qinzhou-Fangcheng trough in Early Silurian and that the exhalative pyrite mineralization was triggered by the postcollisional extension of the margin of Cathaysia Block after the intracontinental collision between Cathaysia Block and Yangtze Block during Late Caledonian stage.
基金Supported by the National Natural Science Foundation of China(Grant No.31872946)National Key R&D Program(2016YFD0100204-8)+2 种基金National Basic Project of Science and Technology(2012FY110200)National Characteristic Vegetable Industry Technology System(CARS-24-A-01)Crop Germplasm Resources Protection Project of the Ministry of Agriculture(2016NWB037)
文摘Wuchuan Gelao and Miao Autonomous County is located in the northeast of Guizhou Province,and in the border of Guizhou and Chongqing,having a subtropical humid monsoon climate. There is no severe heat in summer,and no severe cold in winter. It has distinct national characteristics,and there are many biological resources with national characteristics. A systematic investigation of biological resources in the county for nearly a month was carried out by organizing a professional investigation team. The investigation covered 5 townships and we visited 12 village committees and 26 villagers' groups,involving three ethnic groups: Gelao,Tujia and Miao. The biological resources closely related to the agricultural production and life of local ethnic groups were investigated,collected and sorted out. A total of 230 samples of all kinds of resources were collected,including 47 food crops,75 vegetables and annual crops,37 fruit trees and perennial crops,and 71 medicinal plants. Of these,a total of 73 were unique,superior and special resources. Based on general investigation and professional investigation,this paper analyzes the present situation,growth and decline of local agricultural biological resources,and puts forward some suggestions for the protection,development and utilization of agricultural biological resources.
