The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, weste...The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.展开更多
There are abundant hydrothermal sedimentary structures and plant fragment fossils in the siliceous rocks from the Lincang Ge deposit. The major element compositions of these siliceous rocks are characterized by high c...There are abundant hydrothermal sedimentary structures and plant fragment fossils in the siliceous rocks from the Lincang Ge deposit. The major element compositions of these siliceous rocks are characterized by high content SiO2, low TiO2 and Al2O3concentrations, and low Al/(Al+Fe+Mn) ratios (0.010 on average). The siliceous rocks are distinctly enriched in Ge, Sb, As, W, and secondly enriched in Cs, U, Mo and Tl. Their total REE content are generally less than 1μg/g, LREE relatively concentrated, and the values of Eu anomaly and Ce anomaly vary from 0.452 to 5.141 and 0.997 to 1.174, respectively. Their NAS-normalized REE patterns are plain or left-inclined. The Oxygen isotope compositions of these siliceous rocks are similar to those of the hydrothermal siliceous sinter. The above characteristics, as well as the geological setting of the deposit, indicate these siliceous rocks formed in continental hydrothermal envi- ronment. As the interlayer or cliff of the Ge-rich coal seams, siliceous rocks tightly contacted with ore-body, and the contents of Ge in siliceous rocks vary from 5.6 to 360 μg/g (78 μg/g on aver- age). The Ge content increased in coal which close to the siliceous rocks. With the increase of Ge content, the typical trace element ratios (i.e., Ge/Ga, Nb/Ta and U/Th) and REE patterns of Ge-rich coal are more close to those of the siliceous rocks. The Ge concentrated in coal seams of the Lincang Ge deposit might be transported by the hydrothermal water, which demonstrated by the siliceous rocks, during the coal-forming processes.展开更多
Objective The Lincang granitic batholith, extending over 370 km from north to south with an area of more than 10000 km2, is the major part of the Sanjiang region in western Yunnan, SW China, and is one key area to st...Objective The Lincang granitic batholith, extending over 370 km from north to south with an area of more than 10000 km2, is the major part of the Sanjiang region in western Yunnan, SW China, and is one key area to study the evolution of the Tethys. Previous studies all agreed that the Lincang batholith was formed in the Triassic, and widely considered its formation to be the result of Paleo- Tethyan orogeny （Dong et al., 2013）. However, the early Ordovician syenogranite has been discovered recently for the first tirne in the Lincang batholith, and its petrologic and geochronological results are presented here to provide evidence in support of its association with Proto-Tethyan orogeny. This new discovery has important significance lbr understanding the geodynamic history of the Lincang batholith and tectonic evolution of the Sanjiang region.展开更多
In the context of the“Belt and Road Initiative”,the sustainable development of border cities is paramount for facilitating intergovernmental exchanges.Using the system dynamics approach,we integrated border policy f...In the context of the“Belt and Road Initiative”,the sustainable development of border cities is paramount for facilitating intergovernmental exchanges.Using the system dynamics approach,we integrated border policy factors to create the Border City Coordinated Development(BCCD-SD)model,encompassing three dimensions:Economic,Social,and Resource-Environment.Furthermore,a comprehensive evaluation indicator,the City Coordinated Development Index(CCDI),was devised.Using Lincang City in Southwest China as a case study,this article examines the trends in city development under three scenarios:Inertial Development,Rapid Development,and Green Development.The research findings demonstrate that the model adeptly captures trends in the city coordinated development indicators.Among the three scenarios,the rapid development scenario stands out,yielding the most favorable economic indicators,superior public infrastructure,and the highest employed population.However,the rapid development path,which is heavily focused on economic growth,intensifies resource and environmental pressures,giving rise to sustainability challenges.In contrast,although the green development scenario trails slightly in economic performance compared to rapid development,it fosters a larger urban population and transition of the employed population into citizens while excelling in resource and environmental aspects.Overall,the CCDI attains its highest score under the green development scenario,surpassing those of rapid and inertia development,signifying superior city development coordination along the green path.This scenario effectively combines economic growth,social progress,and resource-environment protection.This study also emphasizes the pivotal role of ports in the coordinated development of border cities and underscores the necessity of expediting the transition from a“gateway”economy to a“port+”economy.One objective of this article is to encourage border cities to serve as more effective windows to the outside world,promote regional coo展开更多
The mineralization is related closely to sedimentation, diagenesis and hydrothermal processes. In this paper, investigations are carried out on coal occurrence, maceral composition, inorganic minerals, trace elements ...The mineralization is related closely to sedimentation, diagenesis and hydrothermal processes. In this paper, investigations are carried out on coal occurrence, maceral composition, inorganic minerals, trace elements and huminite reflectance. It is concluded that the source of Lincang superlarge deposit is mainly the muscovite granite in the west edge of the basin. During sedimentation, Ge (germanium) was leached out and entered the basin. Ge was adsorbed by lower organism and humic substances in water. Lincang lignite underwent three thermal processes: peatification, early diagenesis and hydrothermal transformation. During peatification, Ge was adsorbed or complexed by humic colloids. During early diagenesis, the Ge associated with humic acids was hard to mobilize or transport. Most of Ge entered the structure of huminite while a small amount of Ge was associated with residual humic acids as complex or humate. During hydrothermal transformation, the heated natural water or deep fluid from basement encountered the coal layer within tectonic weak zone. SO 2- 4 was reduced by coal organic matter. Pyrite and calcite formed. Hydrothermal process did not contribute significantly to mineralization.展开更多
定量评估可持续发展目标(Sustainable Development Goals,SDGs)的进展和指标间复杂的相互作用对于监测SDGs的实现进度以及指导政策制定和实施至关重要。以国家可持续发展议程创新示范区(临沧市)为研究区,基于统计、遥感和监测等地球大数...定量评估可持续发展目标(Sustainable Development Goals,SDGs)的进展和指标间复杂的相互作用对于监测SDGs的实现进度以及指导政策制定和实施至关重要。以国家可持续发展议程创新示范区(临沧市)为研究区,基于统计、遥感和监测等地球大数据,在SDGs全球指标框架的基础上,通过实地调研,结合临沧市地域特色和数据获取情况,选取70个SDGs指标构建了评估边疆多民族欠发达地区SDGs进程的指标体系。在此基础上,计算了2015—2020年临沧市16个SDGs得分值和可持续发展综合指数,评价了临沧市SDGs进展状况,提出了临沧市可持续发展面临的关键挑战及解决对策。研究表明,2015—2020年临沧市SDG 6、SDG 7和SDG 13基本保持较高的得分值,其余目标和可持续发展综合指数均呈现增大趋势。在SDGs发展进程方面,16个目标均具有较好的发展进程,SDG 5年均增长率最大,SDG 13基本保持不变;此外,有81%的SDGs指标具有较好的发展进程。该研究可为其他典型示范区推进可持续发展建设提供参考,为推进中国乃至全球欠发达山区可持续发展提供良好借鉴。展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.40473019,40421303 and 40334039)the Chinese Academy of Sciences(Grant No.KZCXZ-SW-117).
文摘The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.
基金jointly supported by the State Key Fundamental Research Developing and Planning Program of China(Grant No.G1999043210)the National Natural Science Foundation of China(Grant No.40302018).
文摘There are abundant hydrothermal sedimentary structures and plant fragment fossils in the siliceous rocks from the Lincang Ge deposit. The major element compositions of these siliceous rocks are characterized by high content SiO2, low TiO2 and Al2O3concentrations, and low Al/(Al+Fe+Mn) ratios (0.010 on average). The siliceous rocks are distinctly enriched in Ge, Sb, As, W, and secondly enriched in Cs, U, Mo and Tl. Their total REE content are generally less than 1μg/g, LREE relatively concentrated, and the values of Eu anomaly and Ce anomaly vary from 0.452 to 5.141 and 0.997 to 1.174, respectively. Their NAS-normalized REE patterns are plain or left-inclined. The Oxygen isotope compositions of these siliceous rocks are similar to those of the hydrothermal siliceous sinter. The above characteristics, as well as the geological setting of the deposit, indicate these siliceous rocks formed in continental hydrothermal envi- ronment. As the interlayer or cliff of the Ge-rich coal seams, siliceous rocks tightly contacted with ore-body, and the contents of Ge in siliceous rocks vary from 5.6 to 360 μg/g (78 μg/g on aver- age). The Ge content increased in coal which close to the siliceous rocks. With the increase of Ge content, the typical trace element ratios (i.e., Ge/Ga, Nb/Ta and U/Th) and REE patterns of Ge-rich coal are more close to those of the siliceous rocks. The Ge concentrated in coal seams of the Lincang Ge deposit might be transported by the hydrothermal water, which demonstrated by the siliceous rocks, during the coal-forming processes.
基金financially supported by the National Nature Science Foundation of China(No.41602049)China Postdoctoral Science Foundation(No.2015M582529)+1 种基金China Geological Survey(No.121201010000150007-24 and DD20160107-03)the Foundation of Sichuan Education Department(Grant:16ZB0109)
文摘Objective The Lincang granitic batholith, extending over 370 km from north to south with an area of more than 10000 km2, is the major part of the Sanjiang region in western Yunnan, SW China, and is one key area to study the evolution of the Tethys. Previous studies all agreed that the Lincang batholith was formed in the Triassic, and widely considered its formation to be the result of Paleo- Tethyan orogeny （Dong et al., 2013）. However, the early Ordovician syenogranite has been discovered recently for the first tirne in the Lincang batholith, and its petrologic and geochronological results are presented here to provide evidence in support of its association with Proto-Tethyan orogeny. This new discovery has important significance lbr understanding the geodynamic history of the Lincang batholith and tectonic evolution of the Sanjiang region.
基金The National Natural Science Foundation of China(42130508).
文摘In the context of the“Belt and Road Initiative”,the sustainable development of border cities is paramount for facilitating intergovernmental exchanges.Using the system dynamics approach,we integrated border policy factors to create the Border City Coordinated Development(BCCD-SD)model,encompassing three dimensions:Economic,Social,and Resource-Environment.Furthermore,a comprehensive evaluation indicator,the City Coordinated Development Index(CCDI),was devised.Using Lincang City in Southwest China as a case study,this article examines the trends in city development under three scenarios:Inertial Development,Rapid Development,and Green Development.The research findings demonstrate that the model adeptly captures trends in the city coordinated development indicators.Among the three scenarios,the rapid development scenario stands out,yielding the most favorable economic indicators,superior public infrastructure,and the highest employed population.However,the rapid development path,which is heavily focused on economic growth,intensifies resource and environmental pressures,giving rise to sustainability challenges.In contrast,although the green development scenario trails slightly in economic performance compared to rapid development,it fosters a larger urban population and transition of the employed population into citizens while excelling in resource and environmental aspects.Overall,the CCDI attains its highest score under the green development scenario,surpassing those of rapid and inertia development,signifying superior city development coordination along the green path.This scenario effectively combines economic growth,social progress,and resource-environment protection.This study also emphasizes the pivotal role of ports in the coordinated development of border cities and underscores the necessity of expediting the transition from a“gateway”economy to a“port+”economy.One objective of this article is to encourage border cities to serve as more effective windows to the outside world,promote regional coo
文摘The mineralization is related closely to sedimentation, diagenesis and hydrothermal processes. In this paper, investigations are carried out on coal occurrence, maceral composition, inorganic minerals, trace elements and huminite reflectance. It is concluded that the source of Lincang superlarge deposit is mainly the muscovite granite in the west edge of the basin. During sedimentation, Ge (germanium) was leached out and entered the basin. Ge was adsorbed by lower organism and humic substances in water. Lincang lignite underwent three thermal processes: peatification, early diagenesis and hydrothermal transformation. During peatification, Ge was adsorbed or complexed by humic colloids. During early diagenesis, the Ge associated with humic acids was hard to mobilize or transport. Most of Ge entered the structure of huminite while a small amount of Ge was associated with residual humic acids as complex or humate. During hydrothermal transformation, the heated natural water or deep fluid from basement encountered the coal layer within tectonic weak zone. SO 2- 4 was reduced by coal organic matter. Pyrite and calcite formed. Hydrothermal process did not contribute significantly to mineralization.
