The Shihu gold deposit, situated in the Taihang Mesozoic orogen of the North China Craton (NCC), is hosted by ductile-brittle faults within Archean metamorphic core complex. The deposit is characterized by gold-bear...The Shihu gold deposit, situated in the Taihang Mesozoic orogen of the North China Craton (NCC), is hosted by ductile-brittle faults within Archean metamorphic core complex. The deposit is characterized by gold-bearing quartz-polymetallic sulfides veins. The Mapeng granitoids stock and intermediate-basic dikes intruded the metamorphic basement rocks, and are spatially related to gold mineralization. Detailed laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) U-Pb zircon ages of the granitic rocks, dykes and mineralized quartz veins in the studied area reveal its magmatic and mineralized history. The mineralized quartz veins contain inherited zircons with ages of about 2.55 Ga and 1.84 Ga, probably coming from the basement. These two Precambrian events are coeval with those in other parts of the NCC. The Mapeng granitoid stock, the largest intrusion in the area, was emplaced at ca. 130 Ma, and is coeval with magmatic zircon populations from diorites and quartz diorite pophyrites in the same region. The ca. 130 Ma magmatism and gold mineralization were most likely related to an underplating event that took place in the Taihang orogen at Late Mesozoic. The timing of gold mineralization with respect to felsic magmatism in the area is similar to those observed in other major gold-producing provinces in the NCC. This episode is simultaneous with those in the eastern margin of NCC, indicative of a widespread late Yanshanian metallogenic event that was a response to the Early Cretaceous lithosphere in the eastern NCC, in which the mesothermal gold deposits were formed from similar tectono-magmatic environments.展开更多
The Shihu gold deposit, located in the middlesouth section of the core of the Fuping mantle branch structure, is hosted in the Archean Fuping Group and adjacent to the quartz diorite porphyrite. The gold deposit is th...The Shihu gold deposit, located in the middlesouth section of the core of the Fuping mantle branch structure, is hosted in the Archean Fuping Group and adjacent to the quartz diorite porphyrite. The gold deposit is the only large gold deposit with reserves of more than 30 tons gold discovered in western Hebei Province so far. In order to constrain the timing of mineralization of this ore deposit, this paper focuses on the isotopic dating of zircon and pyrite. Zircons in gold-bearing quartz veins are magmatic in origin and no hydrothermal zircon has been found in such quartz veins, indicating that zircons were derived from the wall rocks. U–Pb ages of zircons fall mainly in the two domains: 2492 ± 82 and 136 ± 4 Ma, respectively,indicative of the contribution of the Fuping-Group TTG gneiss and Yanshanian igneous rocks, respectively. The Re–Os isotopic compositions of pyrites in the gold-bearing quartz veins yield an isochron age of 127 ± 31 Ma. Combined with other dating results, we suggest that the main metallogenic age of the Shihu gold deposit is 120–127 Ma.展开更多
The Shihu gold deposit is situated in the central shear zone of the Meso-Cenozoic Fuping metamorphic core complex in the middle-northern part of the Taihang Mountains.This kind of gold deposits named after 'Shihu ...The Shihu gold deposit is situated in the central shear zone of the Meso-Cenozoic Fuping metamorphic core complex in the middle-northern part of the Taihang Mountains.This kind of gold deposits named after 'Shihu type' widely occurs in this region.Gold-bearing quartz veins are their most important industrial orebodies.Detailed laser 40Ar/39Ar geochronology of the mineralized quartz veins in the study area reveals details of its tectono-magmatic history.The 40Ar/39Ar ages for the quartz are between 134.4 Ma and 155.9 Ma with a mean age of 141±4 Ma on the isochron line and 139±7 Ma on the inverse isochron line,respectively,which is interpreted to be the best estimate of the crystalline age of the quartz veins.The gold mineralization was most likely related to an underplating event that took place in the northern part of the Taihang Mountain at ca.140 Ma.The timing of gold mineralization in the area is similar to those observed in other major gold-producing provinces in the NCC.This episode is simultaneous with those in the eastern NCC,indicative of a widespread late Yanshanian metallogenic event that was a response either to the subduction of the Izanagi-Pacific plate beneath eastern China or to the removal of the Early Cretaceous lithosphere in the eastern NCC.The ore-forming material sources may be the Early Precambrian metamorphic basement,instead of intermediate-acid rock bodies and dykes.展开更多
目的 比较几种药典收载石斛与常见市场混淆品种的 mat K基因序列 ,为石斛类药材的鉴定提供分子依据。方法 PCR扩增、测序、PAUP软件分析。结果 非石斛属的几种混淆品与正品石斛间的 mat K基因序列差异远大于正品石斛间的差异 ,PAUP4....目的 比较几种药典收载石斛与常见市场混淆品种的 mat K基因序列 ,为石斛类药材的鉴定提供分子依据。方法 PCR扩增、测序、PAUP软件分析。结果 非石斛属的几种混淆品与正品石斛间的 mat K基因序列差异远大于正品石斛间的差异 ,PAUP4.0构建的树型图亦显示几种石斛属植物聚在一起 ,而非石斛属植物聚在外方。结论 通过 mat K基因序列可以分析石斛及其混淆品间的遗传关系 ,将正品与混淆品区别开来。展开更多
基金funded by National Natural Science Foundation of China (Grant No. 90914002, 41030423,41173062, 40973035)the National Basic Research Program of China (Grant No. 2009CB421003)
文摘The Shihu gold deposit, situated in the Taihang Mesozoic orogen of the North China Craton (NCC), is hosted by ductile-brittle faults within Archean metamorphic core complex. The deposit is characterized by gold-bearing quartz-polymetallic sulfides veins. The Mapeng granitoids stock and intermediate-basic dikes intruded the metamorphic basement rocks, and are spatially related to gold mineralization. Detailed laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) U-Pb zircon ages of the granitic rocks, dykes and mineralized quartz veins in the studied area reveal its magmatic and mineralized history. The mineralized quartz veins contain inherited zircons with ages of about 2.55 Ga and 1.84 Ga, probably coming from the basement. These two Precambrian events are coeval with those in other parts of the NCC. The Mapeng granitoid stock, the largest intrusion in the area, was emplaced at ca. 130 Ma, and is coeval with magmatic zircon populations from diorites and quartz diorite pophyrites in the same region. The ca. 130 Ma magmatism and gold mineralization were most likely related to an underplating event that took place in the Taihang orogen at Late Mesozoic. The timing of gold mineralization with respect to felsic magmatism in the area is similar to those observed in other major gold-producing provinces in the NCC. This episode is simultaneous with those in the eastern margin of NCC, indicative of a widespread late Yanshanian metallogenic event that was a response to the Early Cretaceous lithosphere in the eastern NCC, in which the mesothermal gold deposits were formed from similar tectono-magmatic environments.
基金funded by NSFC (No. 40872137)Hebei Natural Foundation (No. D2015403013)+1 种基金Science and Technology Research Project of Colleges and Universities in Hebei Province (No. ZC2016060)Doctor Foundation of Hebei GEO University (No. BQ201320)
文摘The Shihu gold deposit, located in the middlesouth section of the core of the Fuping mantle branch structure, is hosted in the Archean Fuping Group and adjacent to the quartz diorite porphyrite. The gold deposit is the only large gold deposit with reserves of more than 30 tons gold discovered in western Hebei Province so far. In order to constrain the timing of mineralization of this ore deposit, this paper focuses on the isotopic dating of zircon and pyrite. Zircons in gold-bearing quartz veins are magmatic in origin and no hydrothermal zircon has been found in such quartz veins, indicating that zircons were derived from the wall rocks. U–Pb ages of zircons fall mainly in the two domains: 2492 ± 82 and 136 ± 4 Ma, respectively,indicative of the contribution of the Fuping-Group TTG gneiss and Yanshanian igneous rocks, respectively. The Re–Os isotopic compositions of pyrites in the gold-bearing quartz veins yield an isochron age of 127 ± 31 Ma. Combined with other dating results, we suggest that the main metallogenic age of the Shihu gold deposit is 120–127 Ma.
基金granted by the National Natural Science Foundation of China under the Major Research Plan Key Support Project (Grant No. 90914002)the 111 Project under the Ministry of Education and the State Administration of Foreign Experts Affairs,China (Grant No. B07011)
文摘The Shihu gold deposit is situated in the central shear zone of the Meso-Cenozoic Fuping metamorphic core complex in the middle-northern part of the Taihang Mountains.This kind of gold deposits named after 'Shihu type' widely occurs in this region.Gold-bearing quartz veins are their most important industrial orebodies.Detailed laser 40Ar/39Ar geochronology of the mineralized quartz veins in the study area reveals details of its tectono-magmatic history.The 40Ar/39Ar ages for the quartz are between 134.4 Ma and 155.9 Ma with a mean age of 141±4 Ma on the isochron line and 139±7 Ma on the inverse isochron line,respectively,which is interpreted to be the best estimate of the crystalline age of the quartz veins.The gold mineralization was most likely related to an underplating event that took place in the northern part of the Taihang Mountain at ca.140 Ma.The timing of gold mineralization in the area is similar to those observed in other major gold-producing provinces in the NCC.This episode is simultaneous with those in the eastern NCC,indicative of a widespread late Yanshanian metallogenic event that was a response either to the subduction of the Izanagi-Pacific plate beneath eastern China or to the removal of the Early Cretaceous lithosphere in the eastern NCC.The ore-forming material sources may be the Early Precambrian metamorphic basement,instead of intermediate-acid rock bodies and dykes.
文摘目的 比较几种药典收载石斛与常见市场混淆品种的 mat K基因序列 ,为石斛类药材的鉴定提供分子依据。方法 PCR扩增、测序、PAUP软件分析。结果 非石斛属的几种混淆品与正品石斛间的 mat K基因序列差异远大于正品石斛间的差异 ,PAUP4.0构建的树型图亦显示几种石斛属植物聚在一起 ,而非石斛属植物聚在外方。结论 通过 mat K基因序列可以分析石斛及其混淆品间的遗传关系 ,将正品与混淆品区别开来。