There are giant mineral deposits, including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu, and otherimportant mineral deposits (e.g., Baiyangchang Ag-Cu, Jinman Cu deposits, etc.) in the Lanping Mesozoic-Cenozoic Basin, ...There are giant mineral deposits, including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu, and otherimportant mineral deposits (e.g., Baiyangchang Ag-Cu, Jinman Cu deposits, etc.) in the Lanping Mesozoic-Cenozoic Basin, Yunnan Province, China. The tabular ore-bodies and some veins hosted in terrestrial clastic rocks of the Mesozoic-Cenozoic age and no outcropping of igneous rocks in the giant deposits lead to the proposal of syngenetic origin, but the giant mineral deposits are not stratabound (e.g. MVT, sandstone- and Sedex-type). They formed in a continental red basin with intense crust movement. The mineralization is controlled by structures and lithology and occurs in different strata, and no sedimentary nature and no exhalative sediments are identified in the deposits. The deposits show some relations with organic matter (now asphalt and petroleum) and evaporates (gypsum). The middle-low-temperature (mainly 110℃ to 280℃) mineralization took place at a depth of about 0.9 km to 3.1 km during the early Himalayan (58 to 67 Ma). The salinity of ore-forming fluids is surprisingly low (1.6% to 18.0 wt% (NaCl)eq). Affected by the collision of the Indian and Eurasian plates, the mantle is disturbed under the Lanping Basin. The large-scale mineralization is closely linked with the geodynamics of the crust movement, the mantle and mantle-flux upwelling and igneous activity. Giant mineral deposits and their geodynamic setting are unique in the Lanping Basin.展开更多
Severe soil erosion in the middle and upper reaches of Yangtze River has been regarded as a major environmental problem. The on-site impact of soil erosion on agricultural production and the off-site impact on floods ...Severe soil erosion in the middle and upper reaches of Yangtze River has been regarded as a major environmental problem. The on-site impact of soil erosion on agricultural production and the off-site impact on floods and sedimentation in Yangtze Rive are well known. A quantitative assessment of soil erosion intensity is still scanty for developing appropriate soil erosion control measures for different land use types and zones in this region. This article constructs a localized USLE and estimates the average soil loss in the Jinsha River Region in Yunnan Province, one of the priority areas for soil erosion control in the middle and upper reaches of Yangtze River. The estimation is done under different land uses and zones in this basin. The estimation shows that while soil erosion in the cultivated land is the most severe, 36～40% of the garden and forest land suffers from soil erosion of various degrees due to lack of ground cover and other factors. Soil erosion in the pasture is modest when the ground cover is well maintained. It also confirmed that terracing can reduce soil erosion intensity significantly on the cultivated land. Research findings suggest that sufficient attention must be paid to regeneration of the ground cover in reforestation programs. In addition to mass reforestation efforts, restoration of grassland and terracing of the cultivated land should also play an important role in erosion control.展开更多
Qiangtang basin The north margin of the Qiangtang Basin, which located at the north Tibet region,is Lazhulong\|Xijinwulan (also named Jinshajiang River) suture zone (connect zone), and the south margin is Bangong Lake...Qiangtang basin The north margin of the Qiangtang Basin, which located at the north Tibet region,is Lazhulong\|Xijinwulan (also named Jinshajiang River) suture zone (connect zone), and the south margin is Bangong Lake—Dingqing (Nujiang River) suture zone (connect zone). The West End of the basin is gradually convergent at the West Side from Duoma about 80°meridian, and the East End may reach Muta area at about 95°meridian. According to the Jurassic strata development, the basin could be divided into three parts such the north Qiangtang depression, the Central uplift and the south Qiangtang depression as the first\|order tectonic unit. The direction of marine transgression is from the south of the basin to the north. The Jurassic strata of the basin are mainly marine sediments. The hydrocarbon source rocks occurred in Buqu Formation of the middle Jurassic and Suowa Formation of the upper Jurassic are of important potential for oil & gas exploration, and the hydrocarbon source rock in Quse Formation of the lower Jurassic for this is secondary due to localized distribution in the basin.展开更多
An ichthyofaunistic survey of Mekong tributaries in Lincang Prefecture, Yunnan Province, China yielded a new species of nemacheilid loach, herein described as Schistura sexnubes species nova. The new species is readil...An ichthyofaunistic survey of Mekong tributaries in Lincang Prefecture, Yunnan Province, China yielded a new species of nemacheilid loach, herein described as Schistura sexnubes species nova. The new species is readily distinguishable from its congeners by the following combination of characters： 8＋8 branched caudal fin rays, an incomplete lateral line, a dissociated caudal bar, a shallow caudal peduncle depth （7.6%-9.6% SL; respectively caudal peduncle 1.76-1.95 times longer than deep）, a diminutive size of less than 50 mm SL, and no sexual dimorphism. A dorsocephalic pattern consisting of a black, forward directed V-shaped formation located between the nares, and a white, ovoid blotch on the upper operculum serves as an autapomorphy.展开更多
The paleohydrogeologic condition and the tectonic stress field during the mineralization epoch of the Au (Cu) ore fluid in the bordering orogenic belt of Simao-Nanping basin reveal that the complicated paleohydrodynam...The paleohydrogeologic condition and the tectonic stress field during the mineralization epoch of the Au (Cu) ore fluid in the bordering orogenic belt of Simao-Nanping basin reveal that the complicated paleohydrodynamic condition during the Devonian-Carboniferous period in the northern Ailao-shan was favorable for the pre-enrichment of the mineral elements, and that the migration and the distribution of the groundwater were controlled by the tectonic stress field and driven by temperature and hydraulic gradients during the Yanshan-Himalayan movement epoch. Therefore, the determination of the low-pressure zone of the maximum principal stress is effective for the location of the Au deposits (ore spots).展开更多
Through nearly seven months of investigation and research, detailed information and data on vegetation resources, land resources and other ecological resources in the Taojia small river basin were obtained, and the da...Through nearly seven months of investigation and research, detailed information and data on vegetation resources, land resources and other ecological resources in the Taojia small river basin were obtained, and the data were analyzed and processed. The results show that due to the destruction of forest vegetation, the steep slope reclamation and water channel leakage in the Taojia small river basin, well fields and forest land at multiple sites in the basin have been buried by mud and rock, and abundant forest vegetation distributed in the middle and upper reaches has reduced to the situation of a forest coverage rate of only 15.5%. As a result, a vicious circle of "ecological destruction, soil erosion, farmland reduction, poverty, steep slope cultivation, ecological destruction" has been formed. Based on the analysis of the basic ecological background of the basin, six ecological restoration proposals such as planting soil and water conservation forests and fruit trees and blockading protection were proposed, in order to provide support for restoring the ecological environment of the basin and achieving sustainable development of the ecological environment within the basin.展开更多
Since the Mesozoic, abundant metal and salt deposits have been formed in the Lanping Basin, western Yunnan Province, Southwest China, constituting a well-known hydrothermal ore belt in China. Most of the deposits are ...Since the Mesozoic, abundant metal and salt deposits have been formed in the Lanping Basin, western Yunnan Province, Southwest China, constituting a well-known hydrothermal ore belt in China. Most of the deposits are meso-epithermal hydrothermal deposits. This paper preliminarily deals with the mineralization ages of hydrothermal deposits in the Lanping Basin by using the apatite fission track method, and integrates the spatial distribution of the deposits and their regional geological backgrounds, to give the preliminary viewpoints as follows: (1) the apatite fission track ages acquired range from 19.9 Ma to 52.8 Ma, much younger than those of their host strata, so they may be considered to be mineralization ages, which represent the late mineralization period; (2) the apatite fission track ages tend to become younger from the west to the middle of the basin, indicating that the latest evolution of tectono-fluid and/or metallogenic processes of the middle basin ended later than that in the west; (3) in the Paleogene, most of the Cu deposits were formed in the western part of the basin; (4) the major metallogenic processes occur between the Paleogene and the Neogene, because the eastern and western edges of the basin were subducted into and collided with its bilateral continental blocks, respectively, and the central fault was strongly activated, which led to the processes of large-scale ore-forming fluids, and their differentiation and transport because of the variation of their physical and chemical properties. Having been squeezed and uplifted, the Lanping Basin became an intermontane basin that contains many kinds of fluid traps resulting in the formation of different types of ore deposits (for example, Pb-Zn, Cu, Ag) of different scales in the middle of the basin. Simultaneously, the fluids with volatile elements such as Hg, Sb and As were transported upwards along the central fault system and diffused into its subordinate fractures, thus leading to the metallogenic processes of Hg, Sb and As in the eastern composite anticline of the Lanping Basin; (5) and later, these ore deposits experienced reformation and oxidization. To summarize,deep giant faults were active in the basin, and metallogenic processes were constrained by the evolution of tectono-fluids in the Lanping Basin. Simultaneously, the occurrence of the metallogenic processes made the nature of fluid and the structural environment change, which led to returning and recycling of the fluids. Multi-stage and zonational metallogenic processes are the characteristics of the ore deposits in the Lanping Basin.展开更多
Interest in the ore\|forming histories of basins has grown rapid since 1960 and is now intensive. The main reason behind the acceleration is the increasing awareness that the natural processes responsible for generati...Interest in the ore\|forming histories of basins has grown rapid since 1960 and is now intensive. The main reason behind the acceleration is the increasing awareness that the natural processes responsible for generating metal deposits in the sedimentary basin from the source rocks of the beneath the basin and intensively hydrothermal activity in the basin. Observations made in different continental margin basin systems and superlarge deposits in Chinese Yunnan\|Guizhou\|Guangxi Province on the eastern margin of the Qingzang (Himalaya—Karakoram—Tibet) were investigated in terms of geodynamics of basin formation. Geotectonically, the area is situated in the conjoint between the Tethys—Himalaya and the Marginal\|Pacific tectonic domain, characterized by very complex geological structure, typical basin\|mountain tectonics, abundant Superlarge deposits.展开更多
In this study, six fish species of five families are reported for the first time from Yunnan Province, China. The nemacheilid Schistura arnplizona Kottelat, 2000 is reported from the Luosuojiang River and Nanlahe Rive...In this study, six fish species of five families are reported for the first time from Yunnan Province, China. The nemacheilid Schistura arnplizona Kottelat, 2000 is reported from the Luosuojiang River and Nanlahe River subbasins, Mekong basin; the prochilodontid Prochilodus lineatus （Valenciennes, 1837）, the balitorid Vanmanenia serrilineata Kottelat, 2000, and the tetraodontid Monotrete turgidus Kottelat, 2000, from Nanlahe River subbasin, Mekong basin; the balitorid Beaz^fortia daon （Mai, 1978）, and the belonid Xenentodon canciloides （Bleeker, 1854）, both, from Black River subbasin, Red River basin. The freshwater puffer M. turgidus and the needlefish ,E canciloides have been previously misidentified as Tettraodon leiurus （Bleeker, 1950） and Tylosurus strongylurus （van Hasselt, 1823）, respectively.展开更多
The golden apple snail Pomacea canaliculata （Lamarck 1819） was first recorded at Black Dragon Spring, Dianchi Basin, Baiyi Township, Songming County, Kunming City, Yunnan Province, China, in October 2004. The water ...The golden apple snail Pomacea canaliculata （Lamarck 1819） was first recorded at Black Dragon Spring, Dianchi Basin, Baiyi Township, Songming County, Kunming City, Yunnan Province, China, in October 2004. The water from the spring flows into the Songhuaba Reservoir, the major drinking water resource for Kunming City, and part of the Dianchi Lake basin. This is the first record of this invasive snail in the Dianchi Lake Basin. Pomacea canaliculata originates from Central and South America, and in Asia the snail has spread through deliberate and accidental introductions to the Philippines, Vietnam, Thailand, Laos, Cambodia, Malaysia, Indonesia, Papua New Guinea, Korea, Japan and South China. It has become a major pest in rice-growing areas, resulting in huge damage to crops. Strict prevention and control measures have to be implemented to prevent the spread of the snail in Yunnan, together with public awareness campaigns to inform the public of the dangers of this invasive snail.展开更多
The Lanping sedimentary basin has experienced a five-stage evolution since the late Paleozoic： ocean-continent transformation （late Paleozoic to early mid-Triassic）; intracontinental rift basin （late mid-Triassic ...The Lanping sedimentary basin has experienced a five-stage evolution since the late Paleozoic： ocean-continent transformation （late Paleozoic to early mid-Triassic）; intracontinental rift basin （late mid-Triassic to early Jurassic）; down-warped basin （middle to late Jurassic）; foreland basin （Cretaceous）; and strike-slip basin （Cenozoic）. Three major genetic types of Ag-Cu polymetallic ore deposits, including the reworked hydrothermal sedimentary, sedimentary-hydrothermally reworked and hydrothermal vein types, are considered to be the products of basin fluid activity at specific sedimentary-tectonic evolutionary stages. Tectonic differences of the different evolutionary stages resulted in considerable discrepancy in the mechanisms of formation-transportation, migration direction and emplacement processes of the basin fluids, thus causing differences in mineralization styles as well as in genetic types of ore deposit.展开更多
基金the National Natural Science Foundation of China(40272050)the State Key Basic Research Development Program(2002CB4126007 +1 种基金 G1999043201) the Chinese Post-doctorial Foundation.
文摘There are giant mineral deposits, including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu, and otherimportant mineral deposits (e.g., Baiyangchang Ag-Cu, Jinman Cu deposits, etc.) in the Lanping Mesozoic-Cenozoic Basin, Yunnan Province, China. The tabular ore-bodies and some veins hosted in terrestrial clastic rocks of the Mesozoic-Cenozoic age and no outcropping of igneous rocks in the giant deposits lead to the proposal of syngenetic origin, but the giant mineral deposits are not stratabound (e.g. MVT, sandstone- and Sedex-type). They formed in a continental red basin with intense crust movement. The mineralization is controlled by structures and lithology and occurs in different strata, and no sedimentary nature and no exhalative sediments are identified in the deposits. The deposits show some relations with organic matter (now asphalt and petroleum) and evaporates (gypsum). The middle-low-temperature (mainly 110℃ to 280℃) mineralization took place at a depth of about 0.9 km to 3.1 km during the early Himalayan (58 to 67 Ma). The salinity of ore-forming fluids is surprisingly low (1.6% to 18.0 wt% (NaCl)eq). Affected by the collision of the Indian and Eurasian plates, the mantle is disturbed under the Lanping Basin. The large-scale mineralization is closely linked with the geodynamics of the crust movement, the mantle and mantle-flux upwelling and igneous activity. Giant mineral deposits and their geodynamic setting are unique in the Lanping Basin.
基金the result of project(No.40061006)funded by the National Natural Sciences Foundation of China
文摘Severe soil erosion in the middle and upper reaches of Yangtze River has been regarded as a major environmental problem. The on-site impact of soil erosion on agricultural production and the off-site impact on floods and sedimentation in Yangtze Rive are well known. A quantitative assessment of soil erosion intensity is still scanty for developing appropriate soil erosion control measures for different land use types and zones in this region. This article constructs a localized USLE and estimates the average soil loss in the Jinsha River Region in Yunnan Province, one of the priority areas for soil erosion control in the middle and upper reaches of Yangtze River. The estimation is done under different land uses and zones in this basin. The estimation shows that while soil erosion in the cultivated land is the most severe, 36～40% of the garden and forest land suffers from soil erosion of various degrees due to lack of ground cover and other factors. Soil erosion in the pasture is modest when the ground cover is well maintained. It also confirmed that terracing can reduce soil erosion intensity significantly on the cultivated land. Research findings suggest that sufficient attention must be paid to regeneration of the ground cover in reforestation programs. In addition to mass reforestation efforts, restoration of grassland and terracing of the cultivated land should also play an important role in erosion control.
文摘Qiangtang basin The north margin of the Qiangtang Basin, which located at the north Tibet region,is Lazhulong\|Xijinwulan (also named Jinshajiang River) suture zone (connect zone), and the south margin is Bangong Lake—Dingqing (Nujiang River) suture zone (connect zone). The West End of the basin is gradually convergent at the West Side from Duoma about 80°meridian, and the East End may reach Muta area at about 95°meridian. According to the Jurassic strata development, the basin could be divided into three parts such the north Qiangtang depression, the Central uplift and the south Qiangtang depression as the first\|order tectonic unit. The direction of marine transgression is from the south of the basin to the north. The Jurassic strata of the basin are mainly marine sediments. The hydrocarbon source rocks occurred in Buqu Formation of the middle Jurassic and Suowa Formation of the upper Jurassic are of important potential for oil & gas exploration, and the hydrocarbon source rock in Quse Formation of the lower Jurassic for this is secondary due to localized distribution in the basin.
基金Special acknowledgement to Jing WANG for her tremendous support during the preparation and organization of the excursion as well as encouragement during the paper＇s compilation, Peng-Fei SHANG and Ming-Tao CUI for their helpful assistance, Lina Du, Kunming Institute of Zoology （KIZ）, Chinese Academy of Sciences, for her patience with me reviewing specimens in the institute＇s collection, Xiao- Yong CHEN and Jun-Xing YANG, both K/Z, for their support in terms of literature and material, my travel companion Michael Bisset, Tsinghua University, Beijing, for his overall support and help during the excursion.
文摘An ichthyofaunistic survey of Mekong tributaries in Lincang Prefecture, Yunnan Province, China yielded a new species of nemacheilid loach, herein described as Schistura sexnubes species nova. The new species is readily distinguishable from its congeners by the following combination of characters： 8＋8 branched caudal fin rays, an incomplete lateral line, a dissociated caudal bar, a shallow caudal peduncle depth （7.6%-9.6% SL; respectively caudal peduncle 1.76-1.95 times longer than deep）, a diminutive size of less than 50 mm SL, and no sexual dimorphism. A dorsocephalic pattern consisting of a black, forward directed V-shaped formation located between the nares, and a white, ovoid blotch on the upper operculum serves as an autapomorphy.
基金This paper is supported by NKBRSF Project (No. G1999043205) the Returned Studenes Fund of CME.
文摘The paleohydrogeologic condition and the tectonic stress field during the mineralization epoch of the Au (Cu) ore fluid in the bordering orogenic belt of Simao-Nanping basin reveal that the complicated paleohydrodynamic condition during the Devonian-Carboniferous period in the northern Ailao-shan was favorable for the pre-enrichment of the mineral elements, and that the migration and the distribution of the groundwater were controlled by the tectonic stress field and driven by temperature and hydraulic gradients during the Yanshan-Himalayan movement epoch. Therefore, the determination of the low-pressure zone of the maximum principal stress is effective for the location of the Au deposits (ore spots).
基金Supported by National Technology R&D Program(0BAC06B02)
文摘Through nearly seven months of investigation and research, detailed information and data on vegetation resources, land resources and other ecological resources in the Taojia small river basin were obtained, and the data were analyzed and processed. The results show that due to the destruction of forest vegetation, the steep slope reclamation and water channel leakage in the Taojia small river basin, well fields and forest land at multiple sites in the basin have been buried by mud and rock, and abundant forest vegetation distributed in the middle and upper reaches has reduced to the situation of a forest coverage rate of only 15.5%. As a result, a vicious circle of "ecological destruction, soil erosion, farmland reduction, poverty, steep slope cultivation, ecological destruction" has been formed. Based on the analysis of the basic ecological background of the basin, six ecological restoration proposals such as planting soil and water conservation forests and fruit trees and blockading protection were proposed, in order to provide support for restoring the ecological environment of the basin and achieving sustainable development of the ecological environment within the basin.
基金This work was financially supported by the State Key Laboratory of Loess and Quaternary Geology (Grant No. SKLLQG0507), the National Natural Science Foundation of China (Grant No. 40572124), and CAS Key Laboratory of Marginal Sea Geology (Grant No. MSGL04-4).
文摘Since the Mesozoic, abundant metal and salt deposits have been formed in the Lanping Basin, western Yunnan Province, Southwest China, constituting a well-known hydrothermal ore belt in China. Most of the deposits are meso-epithermal hydrothermal deposits. This paper preliminarily deals with the mineralization ages of hydrothermal deposits in the Lanping Basin by using the apatite fission track method, and integrates the spatial distribution of the deposits and their regional geological backgrounds, to give the preliminary viewpoints as follows: (1) the apatite fission track ages acquired range from 19.9 Ma to 52.8 Ma, much younger than those of their host strata, so they may be considered to be mineralization ages, which represent the late mineralization period; (2) the apatite fission track ages tend to become younger from the west to the middle of the basin, indicating that the latest evolution of tectono-fluid and/or metallogenic processes of the middle basin ended later than that in the west; (3) in the Paleogene, most of the Cu deposits were formed in the western part of the basin; (4) the major metallogenic processes occur between the Paleogene and the Neogene, because the eastern and western edges of the basin were subducted into and collided with its bilateral continental blocks, respectively, and the central fault was strongly activated, which led to the processes of large-scale ore-forming fluids, and their differentiation and transport because of the variation of their physical and chemical properties. Having been squeezed and uplifted, the Lanping Basin became an intermontane basin that contains many kinds of fluid traps resulting in the formation of different types of ore deposits (for example, Pb-Zn, Cu, Ag) of different scales in the middle of the basin. Simultaneously, the fluids with volatile elements such as Hg, Sb and As were transported upwards along the central fault system and diffused into its subordinate fractures, thus leading to the metallogenic processes of Hg, Sb and As in the eastern composite anticline of the Lanping Basin; (5) and later, these ore deposits experienced reformation and oxidization. To summarize,deep giant faults were active in the basin, and metallogenic processes were constrained by the evolution of tectono-fluids in the Lanping Basin. Simultaneously, the occurrence of the metallogenic processes made the nature of fluid and the structural environment change, which led to returning and recycling of the fluids. Multi-stage and zonational metallogenic processes are the characteristics of the ore deposits in the Lanping Basin.
文摘Interest in the ore\|forming histories of basins has grown rapid since 1960 and is now intensive. The main reason behind the acceleration is the increasing awareness that the natural processes responsible for generating metal deposits in the sedimentary basin from the source rocks of the beneath the basin and intensively hydrothermal activity in the basin. Observations made in different continental margin basin systems and superlarge deposits in Chinese Yunnan\|Guizhou\|Guangxi Province on the eastern margin of the Qingzang (Himalaya—Karakoram—Tibet) were investigated in terms of geodynamics of basin formation. Geotectonically, the area is situated in the conjoint between the Tethys—Himalaya and the Marginal\|Pacific tectonic domain, characterized by very complex geological structure, typical basin\|mountain tectonics, abundant Superlarge deposits.
基金I am thankful to Jun-Xing YANG, Xiao-Yong CHEN, Lan-Ping ZHENG and Li- Na DU of the Kunming Institute for Zoology （KIZ） and their team around for giving me access to literature and nearly unrestricted access to the collection room of KIZ. I also thankful to Ting-Yi ZHAO of KIZ, for locating, measuring, and photographing mlmerous lots in the KIZ collection room, to my travel companion Jing Wang for her help and support, to Mike Bisset for his valuable comments on the manuscript and help with the Bleeker （1850） paper, and to Maurice Kottelat, Richard Green, Nguyen Dinh Tao, and Bui The Anh for literature support.
文摘In this study, six fish species of five families are reported for the first time from Yunnan Province, China. The nemacheilid Schistura arnplizona Kottelat, 2000 is reported from the Luosuojiang River and Nanlahe River subbasins, Mekong basin; the prochilodontid Prochilodus lineatus （Valenciennes, 1837）, the balitorid Vanmanenia serrilineata Kottelat, 2000, and the tetraodontid Monotrete turgidus Kottelat, 2000, from Nanlahe River subbasin, Mekong basin; the balitorid Beaz^fortia daon （Mai, 1978）, and the belonid Xenentodon canciloides （Bleeker, 1854）, both, from Black River subbasin, Red River basin. The freshwater puffer M. turgidus and the needlefish ,E canciloides have been previously misidentified as Tettraodon leiurus （Bleeker, 1950） and Tylosurus strongylurus （van Hasselt, 1823）, respectively.
文摘The golden apple snail Pomacea canaliculata （Lamarck 1819） was first recorded at Black Dragon Spring, Dianchi Basin, Baiyi Township, Songming County, Kunming City, Yunnan Province, China, in October 2004. The water from the spring flows into the Songhuaba Reservoir, the major drinking water resource for Kunming City, and part of the Dianchi Lake basin. This is the first record of this invasive snail in the Dianchi Lake Basin. Pomacea canaliculata originates from Central and South America, and in Asia the snail has spread through deliberate and accidental introductions to the Philippines, Vietnam, Thailand, Laos, Cambodia, Malaysia, Indonesia, Papua New Guinea, Korea, Japan and South China. It has become a major pest in rice-growing areas, resulting in huge damage to crops. Strict prevention and control measures have to be implemented to prevent the spread of the snail in Yunnan, together with public awareness campaigns to inform the public of the dangers of this invasive snail.
基金supported by the National Natural Science Foundation of China under the grants 40573031 and 40772060the 973 National Basic Research Priorities Program(2006CB701402)+1 种基金the 111 Project(No.B07011)of the Ministry of Educationthe State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences under grant no.GPMR0531
文摘The Lanping sedimentary basin has experienced a five-stage evolution since the late Paleozoic： ocean-continent transformation （late Paleozoic to early mid-Triassic）; intracontinental rift basin （late mid-Triassic to early Jurassic）; down-warped basin （middle to late Jurassic）; foreland basin （Cretaceous）; and strike-slip basin （Cenozoic）. Three major genetic types of Ag-Cu polymetallic ore deposits, including the reworked hydrothermal sedimentary, sedimentary-hydrothermally reworked and hydrothermal vein types, are considered to be the products of basin fluid activity at specific sedimentary-tectonic evolutionary stages. Tectonic differences of the different evolutionary stages resulted in considerable discrepancy in the mechanisms of formation-transportation, migration direction and emplacement processes of the basin fluids, thus causing differences in mineralization styles as well as in genetic types of ore deposit.
