The mountain rocks in the Dushan Complex are Sr-rich granite with a much higher Sr level than those in other crustal lithospheres in eastern China. That presents a high potential for developing Sr-rich mineral water. ...The mountain rocks in the Dushan Complex are Sr-rich granite with a much higher Sr level than those in other crustal lithospheres in eastern China. That presents a high potential for developing Sr-rich mineral water. In this study, 6 groups of rock samples, together with 30 groups of water samples, were collected. Combining with the existing data, the Sr contents in three different types of underground water were obtained, which are the Quaternary pore water, the meshed bedrock fissure water in weathered zones and the tectonic bedrock fissure water. On the basis of preliminary understanding for the distribution characteristics of Sr-rich mineral water in the Dushan Mountain region, the causes for the Sr-rich mineral water were investigated. Our results showed that the Sr content of the rocks in the studied area ranges from 988 to 1 950 μg/g. In the horizontal direction, those in both the pore water and the meshed bedrock fissure water in weathered zones show high values in the west but low ones in the east, and high ones in the south but low ones in the north. Furthermore, both types of water meet the standard for Sr-rich mineral water in the western areas. In the vertical direction, the Sr content shows the lowest value in pore water(the average value is 0.707 mg/L), middle value in the meshed bedrock fissure water in weathered zones(the average value is 1.415 mg/L) and the highest value in the tectonic bedrock fissure water(the average value is 8.331 mg/L). It was thought that the widely-developed Sr-rich granite in this region provides physical sources for the formation of Sr-rich mineral water. The continuous dissolution of Sr during underground water runoff is the internal mechanism. In addition, the hydraulic interrelations may exist between the three vertical aquifers, leading a continuous accumulation of the Sr level during infiltration.展开更多
After mass extinctions,most areas became“ecologically barren areas”lacking or even without ecosystem over an extensive region.Studying the pioneer organisms and the reconstruction process of a new ecosystem in the“...After mass extinctions,most areas became“ecologically barren areas”lacking or even without ecosystem over an extensive region.Studying the pioneer organisms and the reconstruction process of a new ecosystem in the“ecologically barren area”is very important for revealing the evo-lution after bio-mass extinctions.In the Dushan region,Guizhou Province,China,the trace fossils appeared and flourished evidently earlier than body fossils after Frasnian-Famennian(F-F)mass extinction.The pioneer organisms and pathfinders in the“ecologically barren areas”are the trace-makers that are deposit-feeders with relatively simple structure and conformation on or near the deposit surface.The trace-makers have undergone an evolutionary process that their trace structures changed from simple to complex,and their living and moving areas and spaces enlarged from linear to planar and then to three-dimension spaces.Those characters show that the ability of the trace-makers to deposits and their efficiency of looking for food have been enhanced gradually and that those trace-makers constructed gradually a base for the new ecosystem.This process is similar to that of the trace fossils near the Precambrian-Cambrian boundary.In the Dushan area,only the recovery intervals have been identified for the Famennian body fossils,with no eminent radiation interval recognizable due to the Devonian-Carboniferous(C-D)mass ex-tinction.However,both the recovery and radiation intervals may be clearly recognized in the Famen-nian trace fossils based on their conformation and diversity.The evolution and diversification of the trace fossils in the“ecologically barren area”is considered to have played a role of necessary foun-dation for the recovery of body fossils in the ecological chain.With the gradual disappearance of the unfavourable environment factors resulting in the F-F mass extinction,a new ecosystem was reconstructed in the“ecologically barren area”through a three-step process from the“original ecosystem”to“elementary ecosystem”and finally to the“developed eco-system”.The establishment of the new ecosystem has laid a foundation for the recovery of the body fossils thereafter.展开更多
The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figur...The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.展开更多
基金financially supported by scientific research project of Hebei Geological and Mineral Resource Bureau(454-0601-YBN-VKK1)
文摘The mountain rocks in the Dushan Complex are Sr-rich granite with a much higher Sr level than those in other crustal lithospheres in eastern China. That presents a high potential for developing Sr-rich mineral water. In this study, 6 groups of rock samples, together with 30 groups of water samples, were collected. Combining with the existing data, the Sr contents in three different types of underground water were obtained, which are the Quaternary pore water, the meshed bedrock fissure water in weathered zones and the tectonic bedrock fissure water. On the basis of preliminary understanding for the distribution characteristics of Sr-rich mineral water in the Dushan Mountain region, the causes for the Sr-rich mineral water were investigated. Our results showed that the Sr content of the rocks in the studied area ranges from 988 to 1 950 μg/g. In the horizontal direction, those in both the pore water and the meshed bedrock fissure water in weathered zones show high values in the west but low ones in the east, and high ones in the south but low ones in the north. Furthermore, both types of water meet the standard for Sr-rich mineral water in the western areas. In the vertical direction, the Sr content shows the lowest value in pore water(the average value is 0.707 mg/L), middle value in the meshed bedrock fissure water in weathered zones(the average value is 1.415 mg/L) and the highest value in the tectonic bedrock fissure water(the average value is 8.331 mg/L). It was thought that the widely-developed Sr-rich granite in this region provides physical sources for the formation of Sr-rich mineral water. The continuous dissolution of Sr during underground water runoff is the internal mechanism. In addition, the hydraulic interrelations may exist between the three vertical aquifers, leading a continuous accumulation of the Sr level during infiltration.
基金supported by the National Natural Science F oundation of China(Grant No.40172014)the Guizhou University Foundation.
文摘After mass extinctions,most areas became“ecologically barren areas”lacking or even without ecosystem over an extensive region.Studying the pioneer organisms and the reconstruction process of a new ecosystem in the“ecologically barren area”is very important for revealing the evo-lution after bio-mass extinctions.In the Dushan region,Guizhou Province,China,the trace fossils appeared and flourished evidently earlier than body fossils after Frasnian-Famennian(F-F)mass extinction.The pioneer organisms and pathfinders in the“ecologically barren areas”are the trace-makers that are deposit-feeders with relatively simple structure and conformation on or near the deposit surface.The trace-makers have undergone an evolutionary process that their trace structures changed from simple to complex,and their living and moving areas and spaces enlarged from linear to planar and then to three-dimension spaces.Those characters show that the ability of the trace-makers to deposits and their efficiency of looking for food have been enhanced gradually and that those trace-makers constructed gradually a base for the new ecosystem.This process is similar to that of the trace fossils near the Precambrian-Cambrian boundary.In the Dushan area,only the recovery intervals have been identified for the Famennian body fossils,with no eminent radiation interval recognizable due to the Devonian-Carboniferous(C-D)mass ex-tinction.However,both the recovery and radiation intervals may be clearly recognized in the Famen-nian trace fossils based on their conformation and diversity.The evolution and diversification of the trace fossils in the“ecologically barren area”is considered to have played a role of necessary foun-dation for the recovery of body fossils in the ecological chain.With the gradual disappearance of the unfavourable environment factors resulting in the F-F mass extinction,a new ecosystem was reconstructed in the“ecologically barren area”through a three-step process from the“original ecosystem”to“elementary ecosystem”and finally to the“developed eco-system”.The establishment of the new ecosystem has laid a foundation for the recovery of the body fossils thereafter.
基金financially supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2023324)the Hubei Key Laboratory of Paleontology and Geological Environment Evolution,Wuhan Center of China Geological Survey(PEL-202301)+1 种基金the Science and Technology Fundamental Resources Investigation Program(Grand No.2023FY100900)the Natural Science Foundation of China(Grant No.41802018).
文摘The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.
