An important tectonic inversion took place in eastern North China Block(NCB) during Mesozoic, which caused a great lithosphere thinning, reconstruction of basin-range series, powerful interaction between mantle and cr...An important tectonic inversion took place in eastern North China Block(NCB) during Mesozoic, which caused a great lithosphere thinning, reconstruction of basin-range series, powerful interaction between mantle and crust, a vast granitic intrusion and volcanism, and large-scale metallogenic explosion. The time range of the Mesozoic tectonic regime inversion in the eastern North China Block is one of the key issues to understand mechanism of tectonic regime inversion. Our updated results for recognizing the time range are mainly obtained from the following aspects: structural analyses along northern and southern margins of the NCB and within the NCB for revealing tectonic inversion from compression to extension and structural striking from ~EW to NNE; geothermic analyses of the eastern sedimental basins for a great change of thermal history and regime; basin analysis for basin inversion from compression to extension and basin migration from ~EW to NNE; petrological and geochemical studies of volcanic rocks and lowermost crust xenoliths for recognizing peak period of mantle upwelling and intense interaction between mantle and crust, and main metallogenic epoch. All the studies of the above give the same time range from~150-140 Ma to ~110-100Ma, peaking at ~120 Ma.展开更多
The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±AI-rich biotite± tourmaline±garnet, and lack of ...The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±AI-rich biotite± tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 228-225 Ma BP and J2-3 159-156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6--11.1), high A/CNK, Rb/Sr ratios and tDM values (1887-1817 Ma), and REE's tetrad effect (TE1,3=1.13-1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 20 Ma after the major collision of Indosinian Movement (258-243 Ma BP) in Indo-China Peninsula, and early Yanshanian SPGs formed in the background of back-arc extension setting controlled by paleo-Pacific tectonic domain, and J1, the interval of two stages, is the interim from Tethyan to Pacific tectonic domains in South China. These SPGs have similar geological and geochemical characteristics, because they all crystallized from the magma of partial melting of early Proterozoic metasedimentary rocks when the thickened crust (≤50 km) became thinning, decompression, and transmitting of water.展开更多
During the Late Mesozoic Middle Jurassic--Late Cretaceous, basin and range tectonics and associated magmatism representative of an extensional tectonic setting was widespread in southeastern China as a result of Pacif...During the Late Mesozoic Middle Jurassic--Late Cretaceous, basin and range tectonics and associated magmatism representative of an extensional tectonic setting was widespread in southeastern China as a result of Pacific Plate subduction. Basin tectonics consists of post-orogenic （Type I） and intra-continental extensional basins （Type II）. Type I basins developed in the piedmont and intraland during the Late Triassic to Early Jurassic, in which coarse-grained terrestrial clastic sediments were deposited. Type II basins formed during intra-continental crustal thinning and were characterized by the development of grabens and half-grabens. Graben basins were mainly generated during the Middle Jurassic and were associated with bimodal volcanism. Sediments in half-grabens are intercalated with rhyolitic tufts and lavas and are Early Cretaceous in age with a dominance of Late Cretaceous-Paleogene red beds. Ranges are composed of granitoids and bimodal volcanic rocks, A-type granites and dome-type metamorphic core complexes. The authors analyzed lithological, geochemical and geochronological features of the Late Mesozoic igneous rock assemblages and proposed some geodynamical constraints on forming the basin and range tectonics of South China. A comparison of the similarities and differences of basin and range tectonics between the eastern and western shores of the Pacific is made, and the geo- dynamical evolution model of the Southeast China Block during Late Mesozoic is discussed. Studied results suggest that the basin and range terrane within South China developed on a pre-Mesozoic folded belt was derived from a polyphase tectonic evolution mainly constrained by subduction of the western Pacific Plate since the Late Mesozoic, leading to formation of various magmatism in a back-arc exten- sional setting. Its geodynamic mechanism can compare with that of basin and range tectonics in the eastern shore of the Pacific. Differences of basin and range tectonics between both shores of the Pacific, such as mantle plume展开更多
Mesozoic bimodal volcanic rocks of basaltic andesite and rhyolite are widely distributed in the Da Hinggan Range, but their petrogenetic relationships and geodynamic implications are rarely constrained. Detailed studi...Mesozoic bimodal volcanic rocks of basaltic andesite and rhyolite are widely distributed in the Da Hinggan Range, but their petrogenetic relationships and geodynamic implications are rarely constrained. Detailed studies on doleritic and porphyry dikes in the Zhalantun area indicate that they display features of magma mixing, suggesting their coeval formation. In situ zircon U-Pb dating shows that the porphyry was emplaced in the Early Cretaceous with a ^206Pb/^238U age of 130±1 Ma. Zircons from the dolerite also yield an Early Cretaceous emplacement age of 124±2 Ma although some inherited zircons have been identified. These age results indicate that the Early Cretaceous was an important period of magmatism in the Da Hinggan Range. Zircons from porphyry are characterized by positive value of εHf（t） as high as 10.3±0.5 with Hf depleted mantle model age of 349-568 Ma, whereas magmatic zircons from the dolerite have εHf（t） value of 11.0±1.4 with Hf depleted mantel model age of 342-657 Ma, consistent with those from the porphyry. Considering other data on the geological evolution of this area, it is concluded that the mafic magma originated from the partial melting of Paleozoic enriched lithospheric mantle, whereas the felsic magma came from recycling of juvenile crust formed during the Paleozoic. Both of the protoliths are closely related to the subduction of the Paleo-Asian Ocean during the Paleozoic, indicating that the Paleozoic is an important period of large-scale crustal growth in the area.展开更多
为了评估中国钢铁行业CO2减排潜力,利用长期能源替代规划系统(long range energy a lternatives p lann ingsystem,LEAP)软件建立了LEAPCh ina模型。用该模型模拟了3个不同情景下中国钢铁行业2000—2030年CO2排放量及相应的减排潜力。...为了评估中国钢铁行业CO2减排潜力,利用长期能源替代规划系统(long range energy a lternatives p lann ingsystem,LEAP)软件建立了LEAPCh ina模型。用该模型模拟了3个不同情景下中国钢铁行业2000—2030年CO2排放量及相应的减排潜力。根据减排成本评估其可行性并识别重点减排技术。模拟结果表明,相对基准情景,当前政策情景和新政策情景下的年均CO2减排量分别为0.51亿t和1.07亿t,所需要的总的额外资金投入分别为93.4亿美元和809.49亿美元。因此,钢铁行业具有一定的CO2减排潜力,实现减排主要通过行业结构调整和技术进步。如果目前制定的政策措施得到有效实施,那么可以以较低的成本实现减排;但是进一步的减排受制于高昂的成本。展开更多
The Nanling metallogenic belt in South China is characterized by well-developed tungsten-tin mineralization related to multi- ple-aged granitoids. This belt is one of the 5 key prospecting and exploration areas among ...The Nanling metallogenic belt in South China is characterized by well-developed tungsten-tin mineralization related to multi- ple-aged granitoids. This belt is one of the 5 key prospecting and exploration areas among the 19 important metallogenic tar- gets in China. Important progress has been made in recent years in understanding the Nanling granitoids and associated miner- alization, and this paper introduces the latest major findings as follows： （1） there exists a series of Caledonian, Indosinian, and Yanshanian W-Sn-bearing granites; （2） the Sn-bearing Yanshanian granites in the Nanling Range form an NE-SW trending aluminous A-type granite belt that stretches over 350 km. The granites typically belong to the magnetite series, and dioritic micro-granular enclaves with mingling features are very common; （3） the Early Yanshanian Sn- and W-bearing granites pos- sess different petrological and geochemical features to each other： most Sn-bearing granites are metaluminous to weakly per- aluminous biotite （hornblende） granites, with zircon tHe（t） values of ca. -2 to -8, whereas most W-bearing granites are peralu- minous two-mica granites or muscovite granites with CHf（t） values of ca. -8 to -12; （4） based on the petrology and geochemis- try of the W-Sn-bearing granites, mineralogical studies have shown that common minerals such as titanite, magnetite, and bio- tite may be used as indicators for discriminating the mineralizing potential of the Sn-bearing granites. Similarly, W-bearing minerals such as wolframite may indicate the mineralizing potential of the W-bearing granites. Future studies should be fo- cused on examining the internal relationships between the multiple-aged granites in composite bodies, the metallogenic pecu- liarities of multiple-aged W-Sn-bearing granites, the links between melt evolution and highly evolved ore-bearing felsic dykes, and the connections between granite domes and mineralization.展开更多
基金This work was jointly supported by the Chinese Academy of Sciences (Grant No. KZCX1-07) the Ministry of Science and Technology of China (Grant No. G1999402307)the National Natural Science Foundation of China (Grant. No. 40234050).
文摘An important tectonic inversion took place in eastern North China Block(NCB) during Mesozoic, which caused a great lithosphere thinning, reconstruction of basin-range series, powerful interaction between mantle and crust, a vast granitic intrusion and volcanism, and large-scale metallogenic explosion. The time range of the Mesozoic tectonic regime inversion in the eastern North China Block is one of the key issues to understand mechanism of tectonic regime inversion. Our updated results for recognizing the time range are mainly obtained from the following aspects: structural analyses along northern and southern margins of the NCB and within the NCB for revealing tectonic inversion from compression to extension and structural striking from ~EW to NNE; geothermic analyses of the eastern sedimental basins for a great change of thermal history and regime; basin analysis for basin inversion from compression to extension and basin migration from ~EW to NNE; petrological and geochemical studies of volcanic rocks and lowermost crust xenoliths for recognizing peak period of mantle upwelling and intense interaction between mantle and crust, and main metallogenic epoch. All the studies of the above give the same time range from~150-140 Ma to ~110-100Ma, peaking at ~120 Ma.
基金supported by the National Natural Science Foundation of China(Grant No.40132010 and 40072025).
文摘The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±AI-rich biotite± tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 228-225 Ma BP and J2-3 159-156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6--11.1), high A/CNK, Rb/Sr ratios and tDM values (1887-1817 Ma), and REE's tetrad effect (TE1,3=1.13-1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 20 Ma after the major collision of Indosinian Movement (258-243 Ma BP) in Indo-China Peninsula, and early Yanshanian SPGs formed in the background of back-arc extension setting controlled by paleo-Pacific tectonic domain, and J1, the interval of two stages, is the interim from Tethyan to Pacific tectonic domains in South China. These SPGs have similar geological and geochemical characteristics, because they all crystallized from the magma of partial melting of early Proterozoic metasedimentary rocks when the thickened crust (≤50 km) became thinning, decompression, and transmitting of water.
基金funded by the National Basic Research Program of China(973 Program,No.2012CB416701)National Natural Science Foundation of China(Grant 40972132)was partly supported by the State Key Laboratory for Mineral Deposits Research of Nanjing University(No.2008-Ⅰ-01)
文摘During the Late Mesozoic Middle Jurassic--Late Cretaceous, basin and range tectonics and associated magmatism representative of an extensional tectonic setting was widespread in southeastern China as a result of Pacific Plate subduction. Basin tectonics consists of post-orogenic （Type I） and intra-continental extensional basins （Type II）. Type I basins developed in the piedmont and intraland during the Late Triassic to Early Jurassic, in which coarse-grained terrestrial clastic sediments were deposited. Type II basins formed during intra-continental crustal thinning and were characterized by the development of grabens and half-grabens. Graben basins were mainly generated during the Middle Jurassic and were associated with bimodal volcanism. Sediments in half-grabens are intercalated with rhyolitic tufts and lavas and are Early Cretaceous in age with a dominance of Late Cretaceous-Paleogene red beds. Ranges are composed of granitoids and bimodal volcanic rocks, A-type granites and dome-type metamorphic core complexes. The authors analyzed lithological, geochemical and geochronological features of the Late Mesozoic igneous rock assemblages and proposed some geodynamical constraints on forming the basin and range tectonics of South China. A comparison of the similarities and differences of basin and range tectonics between the eastern and western shores of the Pacific is made, and the geo- dynamical evolution model of the Southeast China Block during Late Mesozoic is discussed. Studied results suggest that the basin and range terrane within South China developed on a pre-Mesozoic folded belt was derived from a polyphase tectonic evolution mainly constrained by subduction of the western Pacific Plate since the Late Mesozoic, leading to formation of various magmatism in a back-arc exten- sional setting. Its geodynamic mechanism can compare with that of basin and range tectonics in the eastern shore of the Pacific. Differences of basin and range tectonics between both shores of the Pacific, such as mantle plume
基金This work was financially suppo.rted by the National Natural Science Foundation of China （No. 40372038 and No. 40325006） Special Grant of 0il ＆ Gas Research （XQ-2004-07）.
文摘Mesozoic bimodal volcanic rocks of basaltic andesite and rhyolite are widely distributed in the Da Hinggan Range, but their petrogenetic relationships and geodynamic implications are rarely constrained. Detailed studies on doleritic and porphyry dikes in the Zhalantun area indicate that they display features of magma mixing, suggesting their coeval formation. In situ zircon U-Pb dating shows that the porphyry was emplaced in the Early Cretaceous with a ^206Pb/^238U age of 130±1 Ma. Zircons from the dolerite also yield an Early Cretaceous emplacement age of 124±2 Ma although some inherited zircons have been identified. These age results indicate that the Early Cretaceous was an important period of magmatism in the Da Hinggan Range. Zircons from porphyry are characterized by positive value of εHf（t） as high as 10.3±0.5 with Hf depleted mantle model age of 349-568 Ma, whereas magmatic zircons from the dolerite have εHf（t） value of 11.0±1.4 with Hf depleted mantel model age of 342-657 Ma, consistent with those from the porphyry. Considering other data on the geological evolution of this area, it is concluded that the mafic magma originated from the partial melting of Paleozoic enriched lithospheric mantle, whereas the felsic magma came from recycling of juvenile crust formed during the Paleozoic. Both of the protoliths are closely related to the subduction of the Paleo-Asian Ocean during the Paleozoic, indicating that the Paleozoic is an important period of large-scale crustal growth in the area.
文摘为了评估中国钢铁行业CO2减排潜力,利用长期能源替代规划系统(long range energy a lternatives p lann ingsystem,LEAP)软件建立了LEAPCh ina模型。用该模型模拟了3个不同情景下中国钢铁行业2000—2030年CO2排放量及相应的减排潜力。根据减排成本评估其可行性并识别重点减排技术。模拟结果表明,相对基准情景,当前政策情景和新政策情景下的年均CO2减排量分别为0.51亿t和1.07亿t,所需要的总的额外资金投入分别为93.4亿美元和809.49亿美元。因此,钢铁行业具有一定的CO2减排潜力,实现减排主要通过行业结构调整和技术进步。如果目前制定的政策措施得到有效实施,那么可以以较低的成本实现减排;但是进一步的减排受制于高昂的成本。
基金supported by National Natural Science Foundation of China(Grant Nos.41230315,40730423)Ministry of Science and Technology(Grant No.2012CB416704)China National Geological Survey Bureau(Grant No.12120113067300)
文摘The Nanling metallogenic belt in South China is characterized by well-developed tungsten-tin mineralization related to multi- ple-aged granitoids. This belt is one of the 5 key prospecting and exploration areas among the 19 important metallogenic tar- gets in China. Important progress has been made in recent years in understanding the Nanling granitoids and associated miner- alization, and this paper introduces the latest major findings as follows： （1） there exists a series of Caledonian, Indosinian, and Yanshanian W-Sn-bearing granites; （2） the Sn-bearing Yanshanian granites in the Nanling Range form an NE-SW trending aluminous A-type granite belt that stretches over 350 km. The granites typically belong to the magnetite series, and dioritic micro-granular enclaves with mingling features are very common; （3） the Early Yanshanian Sn- and W-bearing granites pos- sess different petrological and geochemical features to each other： most Sn-bearing granites are metaluminous to weakly per- aluminous biotite （hornblende） granites, with zircon tHe（t） values of ca. -2 to -8, whereas most W-bearing granites are peralu- minous two-mica granites or muscovite granites with CHf（t） values of ca. -8 to -12; （4） based on the petrology and geochemis- try of the W-Sn-bearing granites, mineralogical studies have shown that common minerals such as titanite, magnetite, and bio- tite may be used as indicators for discriminating the mineralizing potential of the Sn-bearing granites. Similarly, W-bearing minerals such as wolframite may indicate the mineralizing potential of the W-bearing granites. Future studies should be fo- cused on examining the internal relationships between the multiple-aged granites in composite bodies, the metallogenic pecu- liarities of multiple-aged W-Sn-bearing granites, the links between melt evolution and highly evolved ore-bearing felsic dykes, and the connections between granite domes and mineralization.
