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Hydrothermal Zircon Geochronology in the Shangxu Gold Deposit and its Implication for the Early Cretaceous Orogenic Gold Mineralization in the Middle Bangonghu–Nujiang Suture Zone 被引量:1
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作者 HUANG Hanxiao LUOSANG Jiancuo +5 位作者 DAI Zuowen LIU Hong FU Jiangang LI Guangming CAO Huawen ZHOU Qing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第4期1249-1259,共11页
As a typical orogenic gold deposit in Tibet,Shangxu gold deposit is located at the Bangong Lake–Nujiang River Metallogenic Belt in the south of Qinghai–Tibet Plateau.In this paper,zircon U-Pb dating,trace elements a... As a typical orogenic gold deposit in Tibet,Shangxu gold deposit is located at the Bangong Lake–Nujiang River Metallogenic Belt in the south of Qinghai–Tibet Plateau.In this paper,zircon U-Pb dating,trace elements and Hf isotopic analysis were performed on Au-bearing quartz veins in the Shangxu gold deposit.Zircons from Au-bearing quartz veins can be divided into three types:detrital,magmatic,and hydrothermal zircons.There are two age peaks in detrital zircons:ca.1700 Ma and ca.2400 Ma.There are two groups of concordant ages including 157±4 Ma(MSWD=0.69)and 120±1 Ma(MSWD=0.19)in magmatic zircons,in whichεH f(t)value of ca.120 Ma from the magmatic zircons range from+8.24 to+12.9.An age of 119±2 Ma(MSWD=0.42)was yielded from hydrothermal zircons,and theirεH f(t)values vary between+15.7 and+16.4.According to sericite Ar-Ar age,this paper suggests that an age of 119±2 Ma from hydrothermal zircons represent the formation age of the Shangxu gold Deposit,and its mineralization should be related to the collision between Lhasa Block and Qiangtang Block.The metallogenic age is basically the same as the diagenetic age of Mugagangri granite,andεH f(t)value of hydrothermal zircon is significantly higher than that of the contemporaneous magmatic zircon,which indicates that there is a genetic relationship between the gold mineralization and the deep crust-mantle magmatism. 展开更多
关键词 zircon U-Pb geochronology quartz vein hydrothermal zircon Shangxu bangong–nujiang metallogenic belt
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^40Ar/^39Ar and Rb-Sr Ages of the Tiegelongnan Porphyry Cu-(Au)Deposit in the Bangong Co-Nujiang Metallogenic Belt of Tibet,China:Implication for Generation of Super-Large Deposit 被引量:34
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作者 LIN Bin CHEN Yuchuan +6 位作者 TANG Juxing WANG Qin SONG Yang YANG Chao WANG Wenlei HE Wen ZHANG Lejun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期602-616,共15页
The Tiegelongnan deposit is a newly discovered super-large porphyry-epithermal Cu-(Au) deposit in the western part of the Bangong Co-Nujiang metallogenic belt, Tibet(China). Field geology and geochronology indicat... The Tiegelongnan deposit is a newly discovered super-large porphyry-epithermal Cu-(Au) deposit in the western part of the Bangong Co-Nujiang metallogenic belt, Tibet(China). Field geology and geochronology indicate that the porphyry mineralization was closely related to the Early Cretaceous intermediate-felsic intrusions(ca. 123–120 Ma). Various epithermal ore and gangue mineral types were discovered in the middle-shallow part of the orebody, indicating the presence of epithermal mineralization at Tiegelongnan. Potassic, propylitic, phyllic and advanced argillic alteration zones were identified. 40Ar/39Ar dating of hydrothermal biotite(potassic zone), sericite(phyllic zone), and alunite(advanced argillic zone) in/around the ore-bearing granodiorite porphyry yielded 121.1±0.6 Ma(1σ), 120.8±0.7 Ma(1σ) and 117.9±1.6 Ma(1σ), respectively. Five hydrothermal mineralization stages were identified, of which the Stage IV pyrite was Rb-Sr dated to be 117.5±1.8 Ma(2σ), representing the end of epithermal mineralization. Field geology and geochronology suggest that both the epithermal and porphyry mineralization belong to the same magmatic-hydrothermal system. The Tiegelongnan super-large Cu-(Au) deposit may have undergone a prolonged magmatichydrothermal evolution, with the major mineralization event occurring at ca.120–117Ma. 展开更多
关键词 40Ar/39Ar and Rb-Sr dating Tiegelongnan Cu-(Au) deposit bangong Co-nujiang metallogenic belt TIBET Proto-Tethys
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Petrology, geochemistry and geochronology of the Zhongcang ophiolite, northern Tibet: implications for the evolution of the Bangong-Nujiang Ocean 被引量:9
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作者 Yue Tang Qingguo Zhai +2 位作者 Peiyuan Hu Xuchang Xiao Haitao Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第5期1369-1381,共13页
Ophiolites are widespread along the Bangong-Nujiang suture zone, northern Tibet. However, it is still debated on the formation ages and tectonic evolution process of these ophiolites. The Zhongcang ophiolite is a typi... Ophiolites are widespread along the Bangong-Nujiang suture zone, northern Tibet. However, it is still debated on the formation ages and tectonic evolution process of these ophiolites. The Zhongcang ophiolite is a typical ophiolite in the western part of the Bangong-Nujiang suture zone. It is composed of serpentinized peridotite, cumulate and isotropic gabbros, massive and pillow basalts, basaltic volcanic breccia, and minor red chert. Zircon SHRIMP Ue Pb dating for the isotropic gabbro yielded weighted mean age of 163.4 ± 1.8 Ma. Positive zircon ε Hf(t) values(+15.0 to +20.2) and mantle-like σ^(18)O values(5.29 ±0.21)% indicate that the isotropic gabbros were derived from a long-term depleted mantle source. The isotropic gabbros have normal mid-ocean ridge basalt(N-MORB) like immobile element patterns with high Mg O, low TiO_2 and moderate rare earth element(REE) abundances, and negative Nb,Ti, Zr and Hf anomalies. Basalts show typical oceanic island basalt(OIB) geochemical features, and they are similar to those of OIB-type rocks of the Early Cretaceous Zhongcang oceanic plateau within the Bangong-Nujiang Ocean. Together with these data, we suggest that the Zhongcang ophiolite was probably formed by the subduction of the Bangong-Nujiang Ocean during the Middle Jurassic. The subduction of the Bangong-Nujiang Tethyan Ocean could begin in the Earlye Middle Jurassic and continue to the Early Cretaceous, and finally continental collision between the Lhasa and Qiangtang terranes at the west Bangong-Nujiang suture zone probably has taken place later than the Early Cretaceous(ca. 110 Ma). 展开更多
关键词 Tibetan plateau bangong-nujiang SUTURE zone OPHIOLITE GEOCHRONOLOGY GEOCHEMISTRY SUBDUCTION
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Variation of Moho Depth across Bangong-Nujiang Suture in Central Tibet—Results from Deep Seismic Reflection Data 被引量:5
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作者 Zhanwu Lu Rui Gao +2 位作者 Hongqiang Li Wenhui Li Xiaosong Xiong 《International Journal of Geosciences》 2015年第8期821-830,共10页
There is a long-term dispute at Moho depth across the Bangong-Nujiang suture (BNS). Due to the complicated and changeable seismic geological condition, it is not easy to acquire images of the reflective Moho in centra... There is a long-term dispute at Moho depth across the Bangong-Nujiang suture (BNS). Due to the complicated and changeable seismic geological condition, it is not easy to acquire images of the reflective Moho in central Tibet. In the support of the SinoProbe project, a series of deep seismic reflection profiles were conducted to image Moho structure across the BNS and the Qiangtang terrane. These profiles extend from the northern Lhasa terrane to the Qiangtang terrane crossing the BNS. Both shot gathers and migration data show clear Moho images beneath the BNS. The Moho depth varies from 75.1 km (~24 s TWT) beneath the northmost Lhasa terrane to 68.9 km (~22 s TWT) beneath southmost Qiangtang terrane, and rises smoothly to 62.6 km (~20 s TWT ) at ~28 km north of the BNS beneath the Qiangtang terrane. We speculate that the Moho appears a 6.2 km sharp offset across the BNS and becomes ~12.5 km shallower from the northmost Lhasa terrane to the south Qiangtang terrane at ~28 km north of the BNS. The viewpoint of Moho depth across the BNS based on deep seismic reflection data is inconsistent with the previous 20 km offset. 展开更多
关键词 MOHO Depth DEEP SEISMIC REFLECTION bangong-nujiang SUTURE TIBET
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Geological Features of the Eastern Sector of the Bangong Co-Nujiang River Suture Zone:Tethyan Evolution 被引量:10
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作者 WANG Jianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第2期229-235,共7页
According to an analysis of the geological features in the eastern sector of the Bangong Co-Nujiang River suture zone, the Tethyan evolution can be divided into three stages. (1) The Embryo-Tethyan stage (Pz1): An imm... According to an analysis of the geological features in the eastern sector of the Bangong Co-Nujiang River suture zone, the Tethyan evolution can be divided into three stages. (1) The Embryo-Tethyan stage (Pz1): An immature volcanic arc developed in Taniantaweng (Tanen Taunggyi) Range, indicating the existence of an Embryo-Tethyan ocean. (2) The Palaeo-Tethyan stage (C-T2: During the Carboniferous the northern side of the Taniantaweng Range was the main domain of the Palaeo-Tethyan ocean, in which developed flysch sediments intercalated with bimodal volcanic rocks and oceanic tholeiite, and Pemian-Early Triassic are granites were superimposed on the Taniantaweng magmatic are; on the southern side the Dêngqên-Nujiang zone started secondary extension during the Carboniferous, in which the Nujiang ophiolite developed, and the Palaeo-Tethyan ocean closed before the Middle Triassic. (3) The Neo-Tethyan stage (T3-E): During the Late Triassic the Dêngqên zone developed into a relatively matural ocean basin, in which the Dêngqên ophiolite was formed. By the end of the Triassic intraocean subduction occurred, and the ocean domain was reduced gradually, and collided and closed by the end of the Early Jurassic, forming the Yazong mélange; then the Tethyan ocean was completely closed. 展开更多
关键词 bangong Co-nujiang River suture zone Tethyan evolution Embryo-Tethys Palaeo-Tethys NEO-TETHYS
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The Characteristics and Significance of Peng Co Peridotites in the Middle Segment of Bangong Co-Nujiang Suture in Tibet 被引量:1
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作者 LU Yuxiao YANG Jingsui +4 位作者 DONG Yufei XIONG Fahui CHEN Xiaojian LI Guanlong BO Rongzhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第S01期37-38,共2页
The Peng Co ophiolite is located to the west of Peng lake in the area of lakes in north Tibet, which belongs to the Baila-Yilashan sub-belt of the the middle Bangong Co-Nujiang ophiolitic belt. The Peng Co ophiolite i... The Peng Co ophiolite is located to the west of Peng lake in the area of lakes in north Tibet, which belongs to the Baila-Yilashan sub-belt of the the middle Bangong Co-Nujiang ophiolitic belt. The Peng Co ophiolite is mainly composed of mantle peridotites, cumulates, diabase dikes. About 70 percent peridotites are harzburgites and 30 percent are lherzolites. Mineral chemistry of the Peng Co lherzolitesare characterized by low Fo contents(88.85–90.33) of olivine and high Al2O3 content(4.26%–7.25%) in pyroxenes. Compared to the primitive mantle, the Peng Co peridotites have relatively higher MgO contents, lower CaO, Al2O3 and TiO2 contents. The total rare-earth element(REE) contents of the lherzolites are 1.11–1.53 ppm, which are lower than those of the primitive mantle. The chondritenormalized REE patterns of the Peng Co peridotites display slight loss in LREE. In the primitive mantle-normalized spider diagram, the Peng Co peridotites exhibit negative Rb and Zr anomalies and intensively positive U, Ta, Sr anomalies. The PGE contents of Peng Co lherzolites are between 22.9–27 ppb. The chondrite-normalized PGE patterns of the Peng Co lherzolites are consistent with that of the primitive mantle. Mineral and whole-rock geochemistry characteristics of the Peng Co lherzolites show an affinity to abyssal peridotites, indicating that it may have formed in the mid-ocean ridge setting. Through quantitative modeling, we conclude that the Peng Co lherzolites formed after 5%–10% degree of partial melting of the spinelphase lherzolite mantle source. The sharp increase of Cr#(56.74–60.84)in Spinel of harzburgites and relatively high Pd/Ir and Rh/Ir ratios suggest that they have experienced melt-rock reaction. The crystallization sequence of Peng Co cumulate is olivine-clinopyroxene-plagioclase. The Mg# value of clinopyroxene in cumulate peridotite ranges from 86.92 to 89.93, and the mean value of Fo is 84.45, which is obviously higher than that of MOR-type ophiolite cumulates. The mineral composition, sequence of magmatic crystallization and mineral components of Peng Co cumulate are similar to those of the cumulate formed by the SSZ-type ophiolite in the subduction zone. Therefore, we can draw a preliminary conclusion that Peng Co lherzolites were formed in an environment of mid oceanic ridge and were remnants of the spinel lherzolite zone which experienced a partial melting of no more than 10%. In the later period, due to the intra-oceanic subduction, it experienced the rock-meltinteraction, and thus formed the SSZ-type cumulate and harzburgite of high Cr value. 展开更多
关键词 bangong Co-nujiang suture zone MOR-type peridotites Peng Co ophiolite partial melting melt-rock reaction
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New Zircon U-Pb Age of the Ore-bearing Porphyry from the Kuga Copper Deposit in the Eastern Bangongco–Nujiang Matallogenic Belt, Tibet 被引量:3
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作者 LIN Bin SONG Yang +2 位作者 LIU Zhibo LIU Zhenyu GAO Yiming 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第2期859-861,共3页
Objective As the third most important copper polymetallic metallogenic belt in Tibet, the Bangongco-Nujiang metallogenic belt (BNMB) has attracted much attention among geoscientists all over the world (Lin Bin et ... Objective As the third most important copper polymetallic metallogenic belt in Tibet, the Bangongco-Nujiang metallogenic belt (BNMB) has attracted much attention among geoscientists all over the world (Lin Bin et al., 2017a). There are two ore clusters in the westem of BNMB, the Duolong giant porphyry-epitherrnal Cu (Au, Ag) ore cluster and the Ga'erqiong-Galalelarge porphyry- skarn Cu (Au) ore cluster (Lin Bin et al., 2017a; 2017b). Now, the latest exploration advances show that the Kuga project is the first economic porphyry-skam copper deposit in the eastern of BNMB, with over 0.4 Mt melt copper (333+334) @ 0.9%. However, the Kuga deposit is poorly studied about its diagenetic age. In this study, we present a zircon U-Pb LA-ICP-MS dating of ore-bearing biotite granite, in order to identify the time of the ore- related magmatism and reveal the relationship with the westem of BNMB. 展开更多
关键词 PB TIBET nujiang Matallogenic Belt New Zircon U-Pb Age of the Ore-bearing Porphyry from the Kuga Copper Deposit in the Eastern bangongco
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The Cretaceous of the Eastern Bangong-Nujiang Suture Zone (Tibet):Tectono-Sedimentation
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作者 Pujun Wang Frank Mattern +3 位作者 Werner Schneider Wanzhu Liu Shikai Li Cai Li 《Global Geology》 2003年第1期34-40,共7页
The ophiolite-bearing Bangong-Nujiang zone (BNZ) traversing central Tibet from east to west separates the Qiangtang block in the north from the Lhasa block in the south. The Cretaceous of the area includes Chuanba For... The ophiolite-bearing Bangong-Nujiang zone (BNZ) traversing central Tibet from east to west separates the Qiangtang block in the north from the Lhasa block in the south. The Cretaceous of the area includes Chuanba Formation (K 1c ), Duoba Formation (K 1d ), Langshan Formation (K 1l ) and Jiangba Formation (K 2j ). The K 1c is composed of black shale, sandy pelite, siltstone, sandstone, coal beds and volcanic rocks, of shallow marine facies. The K 1 d consists of terrestrial siliciclastics intercalated with some calcareous sandstone beds bearing Orbitolina sp. indicating marine influence. The K 1j is carbonate platform deposits of shallow marine and lagoon. The K 2j is characterized by terrestrial thick massive red conglomerate. An active margin related to B-subduction zone is considered to be the geological setting of the Cretaceous sedimentation. 展开更多
关键词 bangong-nujiang SUTURE zone Cretaceous sedimentology tectonics TIBET
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深反射地震成像揭示的班公湖-怒江缝合带中段Moho断阶及其大地构造意义
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作者 程建 刘志伟 +5 位作者 赵文津 史大年 田涛 邓世广 张克强 张若渔 《地质学报》 EI CAS CSCD 北大核心 2024年第1期1-15,共15页
揭示班公湖-怒江(班怒)缝合带Moho(莫霍面)结构对于认识中特提斯洋壳俯冲和南羌塘坳陷成因具有重要地球动力学意义。基于横跨班怒缝合带的深反射地震数据(88°30′E),本文采用了中长波长静校正、噪声压制、优化叠加和叠前深度偏移(P... 揭示班公湖-怒江(班怒)缝合带Moho(莫霍面)结构对于认识中特提斯洋壳俯冲和南羌塘坳陷成因具有重要地球动力学意义。基于横跨班怒缝合带的深反射地震数据(88°30′E),本文采用了中长波长静校正、噪声压制、优化叠加和叠前深度偏移(PSDM)等地震处理技术,获得了深度域地震反射偏移剖面、层速度场和高分辨率Moho结构。由深度域剖面显示,班怒缝合带Moho位于地表以下65~80 km,呈不连续北向抬升趋势,指示在拉萨地块与南羌塘地块之间存在岩石圈上地幔断阶,最大阶步可达15 km。综合分析缝合带两侧的Moho形态认为,这些断阶受南侧拉萨地体的岩石圈上地幔以19.5°北倾俯冲与北侧南羌塘地块的上地壳抬升驱动,可能与深部存在局部熔融相关。班怒缝合带下的Moho结构表明,随着晚侏罗世—早白垩世中特提斯洋闭合,南羌塘地体由边缘海沉积向前陆盆地转换,形成南羌塘坳陷。 展开更多
关键词 深反射地震成像 叠前深度偏移 班公湖-怒江缝合带 Moho界面 南羌塘坳陷
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羌塘地块中西部布木错走滑断裂系的第四纪晚期地表变形特征与构造意义
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作者 韩帅 吴中海 +4 位作者 王世锋 高扬 张圣听 陆诗铭 张铭杲 《地质力学学报》 CSCD 北大核心 2024年第2期298-313,共16页
班公-怒江缝合带(班怒带)是青藏高原内部羌塘地块与拉萨地块之间的重要边界,研究该边界带上共轭走滑断裂第四纪晚期的几何结构与变形特性对于理解高原内部在印度-欧亚板块碰撞作用下形成的空间差异响应和构造模型具有重要意义。位于班... 班公-怒江缝合带(班怒带)是青藏高原内部羌塘地块与拉萨地块之间的重要边界,研究该边界带上共轭走滑断裂第四纪晚期的几何结构与变形特性对于理解高原内部在印度-欧亚板块碰撞作用下形成的空间差异响应和构造模型具有重要意义。位于班怒带西段的布木错断裂系包括北东向布木错断裂和北西向纳屋错断裂,通过遥感解译和野外地质调查,明确了这两条断裂在第四纪晚期的构造特征和最新的地表变形特征。结果显示,两条断裂自第四纪晚期以来的活动特征明显,并且近期都经历过一次大地震,产生了地表破裂。据此推测班怒带西段北西、北东两组断裂的最新活动强度接近,羌塘地块南部边界现今变形可能受控于两组断裂的共同影响,并已延伸至块体内部。以上发现进一步证明,青藏高原内部物质受中—下地壳流的驱动作用,通过走滑断层和正断层持续向北扩展。 展开更多
关键词 班公-怒江缝合带 布木错断裂 纳屋错断裂 共轭走滑 地表破裂 青藏高原
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西藏东巧—北拉地区班公湖—怒江洋俯冲闭合及对南羌塘盆地演化的制约
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作者 张建勇 许强 +4 位作者 曹雨 熊绍云 刘思琪 谈轩宇 谭秀成 《海相油气地质》 CSCD 北大核心 2024年第1期1-16,共16页
应用地层对比、砂岩岩相学和碎屑锆石U-Pb年代学的方法,重建东巧—北拉地区物源转换和班公湖—怒江洋多期次俯冲及微陆块的拼合过程。研究表明:东卡错微陆块南侧的中下侏罗统希湖群下段表现为上三叠统确哈拉群的再旋回沉积,而北侧上段... 应用地层对比、砂岩岩相学和碎屑锆石U-Pb年代学的方法,重建东巧—北拉地区物源转换和班公湖—怒江洋多期次俯冲及微陆块的拼合过程。研究表明:东卡错微陆块南侧的中下侏罗统希湖群下段表现为上三叠统确哈拉群的再旋回沉积,而北侧上段则开始出现来自羌塘地区的物质。这标志着北侧早侏罗世俯冲的东巧分支洋盆消亡,东卡错微陆块在中侏罗世与羌塘地块拼合开始形成初始周缘前陆盆地。接奴群的物源完全来自南羌塘地区,表明周缘前陆盆地在微陆块南侧北拉洋俯冲挤压下持续发育。晚侏罗世—早白垩世(147~141 Ma)拉萨地块和羌塘地块东西向全面碰撞,至早白垩世晚期(约120 Ma)南侧的分支洋盆北拉洋消亡代表碰撞结束。南羌塘地区受班公湖—怒江洋俯冲作用控制在早侏罗世发育由弧前—岩浆弧—弧后盆地组成的“一隆两坳”古地貌,并沉积了曲色组页岩和布曲组石灰岩。微陆块碰撞导致南羌塘盆地的隆起和海平面的下降,形成夏里组含膏质泥岩的潮坪相沉积。随着拉萨地块和羌塘地块的全面碰撞,南羌塘盆地从弧相关盆地卷入前陆盆地褶皱冲断带中,发生差异埋藏和隆升剥蚀。晚侏罗世—早白垩世,南羌塘盆地曲色组烃源岩和布曲组石灰岩在构造挤压作用下发生快速埋藏,进入生油和白云石化阶段,成为南羌塘盆地最重要的成藏期。 展开更多
关键词 班公湖—怒江缝合带 锆石U-PB定年 俯冲闭合过程 物源转换 南羌塘盆地
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青藏高原西北部班公湖流域夏季主要水体H-O同位素组成及其影响因素
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作者 邵玉祥 严步青 +5 位作者 刘旭 蒋钦 陈文彬 龚康 易海洋 李博 《现代地质》 CAS CSCD 北大核心 2024年第2期427-436,共10页
作为高寒内陆区的青藏高原西北部班公湖流域水文数据资料较为匮乏,导致对区域水循环过程和气候环境的认识不够深入,氢氧稳定同位素示踪技术可为解决该问题提供理想途径。本文系统分析班公湖流域夏季含湖水、河水、冰川融水和地下水4种... 作为高寒内陆区的青藏高原西北部班公湖流域水文数据资料较为匮乏,导致对区域水循环过程和气候环境的认识不够深入,氢氧稳定同位素示踪技术可为解决该问题提供理想途径。本文系统分析班公湖流域夏季含湖水、河水、冰川融水和地下水4种不同类型的水体中氢氧同位素的组成,阐释水体氢氧同位素、氘盈余参数沿程变化的特征及其与水体矿化度、高程、经纬度和全球大气降雨线之间的关系,并进一步剖析同位素组成变化的控制因素。结果显示,水体中δ^(2)H和δ^(18)O的波动范围分别为-112.37‰~-24.90‰和-14.84‰~2.01‰,平均值及标准差分别为-76.73‰±26.49‰和-8.43‰±5.24‰。湖水δ^(2)H和δ^(18)O相对其他水体富集,测定结果更偏正值,冰川融水δ^(2)H和δ^(18)O相对其他水体更为贫化。流域水体氢氧同位素的大陆效应总体不明显,部分水体有一定高程效应体现。水体氢氧同位素演化趋势表明,冰川融水与全球大气水线接近,易受大气降雨影响。同时其他水体线的较小截距和斜率值,表明大气降雨不是这些水体的直接补给源。河流沿程的水体δ^(2)H和δ^(18)O呈递增趋势,越远离冰川融水补给端的河水和湖水值越偏正,反映强蒸发的特点。水体氘盈余参数及其与矿化度之间的关系也指示蒸发作用是影响该区域水体氢氧同位素变化的主要因素。 展开更多
关键词 班公湖流域 氢氧同位素 氘盈余参数 空间特征 同位素效应
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怒江干热河谷木棉种子大小的变异格局
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作者 陈凯 杨艳 +2 位作者 徐玲 赵永福 张宏玉 《生态科学》 CSCD 北大核心 2024年第1期88-93,共6页
为揭示怒江干热河谷木棉种子大小的变异格局,在该气候区的不同生境采集木棉种子,测定种子生物量、直径用于量化种子大小,并借助回归模型分析种子大小随环境梯度的变化。结果显示:(1)在怒江干热河谷,木棉种子大小呈正态分布;(2)在不同干... 为揭示怒江干热河谷木棉种子大小的变异格局,在该气候区的不同生境采集木棉种子,测定种子生物量、直径用于量化种子大小,并借助回归模型分析种子大小随环境梯度的变化。结果显示:(1)在怒江干热河谷,木棉种子大小呈正态分布;(2)在不同干热区,种子大小依次为轻度干热区﹥中度干热区﹥重度干热区;(3)木棉种子随海拔升高而呈变小的趋势;(4)木棉种子大小的变异性随海拔(或干旱强度)上升不断减小。结论表明,木棉种子大小受到水热条件的选择压力,在稳定的水热环境中木棉种子更大,其大小的变异性也更高。 展开更多
关键词 怒江干热河谷 木棉 种子大小变异 干热区 海拔
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基于自校正原型网络的泥石流灾害易发性评价——以怒江州为例
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作者 韩俊 王保云 徐繁树 《人民长江》 北大核心 2024年第3期123-133,共11页
为解决泥石流易发性评价中因子选择不一致造成的评价差异问题,以及目前神经网络不能有效提取泥石流特征以提升易发性评价正确率问题,提出了基于自校正原型网络的泥石流灾害易发性评价方法。以沟谷为评价单元,提取沟谷的DEM、高分一号和G... 为解决泥石流易发性评价中因子选择不一致造成的评价差异问题,以及目前神经网络不能有效提取泥石流特征以提升易发性评价正确率问题,提出了基于自校正原型网络的泥石流灾害易发性评价方法。以沟谷为评价单元,提取沟谷的DEM、高分一号和Google Earth遥感影像作为训练数据,引入注意力机制和空洞空间卷积池化金字塔结构构建原型网络的特征提取器,并使用自校正的方法优化原型网络的计算,将未发生泥石流的沟谷图像输入改进后的模型,计算其泥石流灾害易发性指数从而得出泥石流评价等级。运用该模型对怒江州的沟谷进行评价,并与历史灾害数据进行对比。结果表明:模型分类正确率达到86.32%,评价结果中的易发区和高易发区均与历史泥石流沟谷的空间分布较为吻合;相比于传统评价方法,该方法能够较好地自动学习遥感影像中泥石流特征,并实现灾害区域的快速识别与评价。研究成果可为泥石流灾害的研究提供新的思路。 展开更多
关键词 泥石流 易发性评价 原型网络 小样本学习 遥感影像 怒江州
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草地贪夜蛾及二化螟肠道微生物多样性
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作者 魏富雪 王有慧 +1 位作者 柳青 陈文华 《保山学院学报》 2024年第2期13-17,共5页
采用高通量DNA测序技术以及微生物群落分析方法,对怒江下游蒲缥坝草地贪夜蛾、二化螟两种害虫肠道的微生物进行了研究。研究结果显示:单从菌群的Alpha多样性来看,两种昆虫肠道内微生物在物种数和均匀度方面基本相当;两组样本菌群在群落... 采用高通量DNA测序技术以及微生物群落分析方法,对怒江下游蒲缥坝草地贪夜蛾、二化螟两种害虫肠道的微生物进行了研究。研究结果显示:单从菌群的Alpha多样性来看,两种昆虫肠道内微生物在物种数和均匀度方面基本相当;两组样本菌群在群落结构方面虽然存在差异,但不显著;在两组样本共有且相对丰度较高的10个属中,草地贪夜蛾中肠球菌属(Enterococcus)明显高于二化螟;而在二化螟中克雷伯氏菌属(Klebsiella)和气单胞菌属(Aeromonas)的丰度明显高于草地贪夜蛾。 展开更多
关键词 怒江 草地贪夜蛾 二化螟 肠道微生物
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土地生态服务价值估算与补偿标准研究——以云南怒江州为例
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作者 渠立权 吴迪 刘晨 《国土资源科技管理》 2024年第2期12-21,共10页
本文以云南怒江州为研究对象,利用2020年的土地利用、经济、能源数据,综合运用生态服务功能价值法与碳排放法核算生态补偿标准,破解生态补偿中“补多少”的技术问题。结果显示:(1)2020年,怒江州土地生态服务价值为305.25亿元,其中林地... 本文以云南怒江州为研究对象,利用2020年的土地利用、经济、能源数据,综合运用生态服务功能价值法与碳排放法核算生态补偿标准,破解生态补偿中“补多少”的技术问题。结果显示:(1)2020年,怒江州土地生态服务价值为305.25亿元,其中林地生态系统服务价值233.68亿元,占比达到76.55%;(2)2020年怒江州土地生态系统共吸收5619.934×10^(4)t碳,转换为经济价值为153.59亿元;(3)2020年怒江州生态补偿标准区间值为4.12亿元~11.19亿元,取区间均值作为应获得的生态补偿金较为合理,怒江州应获得的生态补偿标准总额为7.655亿元。 展开更多
关键词 土地生态服务价值 土地碳排放 生态补偿标准 云南怒江州
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怒江州泸水市中药材产业高质量发展对策
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作者 黄雪莉 黄祥 +3 位作者 宗四南 罗应祥 尹先斌 蒋平妹 《热带农业科技》 2024年第2期57-60,共4页
怒江州泸水市拥有丰富的中药材资源和悠久的种植历史,具有发展中药材产业独特的优势。文章基于怒江州泸水市中药材产业现状,总结发展中存在的问题,提出相关发展建议。
关键词 中药材 产业发展 怒江
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云南省怒江州经济林资源现状分析及发展对策
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作者 李继品 孟翠萍 《中国林副特产》 2024年第1期89-92,共4页
利用云南省怒江州2017年森林资源规划设计调查成果资料,对怒江州的经济林资源现状进行分析。怒江州经济林资源达82 941.4 hm~2,主要分布区为泸水市、福贡县和兰坪县三个县,提出了因地制宜培育优势特色经济林产业、积极培育新兴经济林产... 利用云南省怒江州2017年森林资源规划设计调查成果资料,对怒江州的经济林资源现状进行分析。怒江州经济林资源达82 941.4 hm~2,主要分布区为泸水市、福贡县和兰坪县三个县,提出了因地制宜培育优势特色经济林产业、积极培育新兴经济林产业经营主体、做大做强泡核桃产业和强化科技支撑体系建设等建议。 展开更多
关键词 怒江州 经济林资源 现状分析 发展对策
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Chronology and Crust-Mantle Mixing of Ore-forming Porphyry of the Bangongco: Evidence from Zircon U-Pb Age and Hf Isotopes of the Naruo Porphyry Copper-Gold Deposit 被引量:12
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作者 ZHOU Xiong FEI Guangchun +3 位作者 ZHOU Yu WEN Chunqi ZHANG Yi YUE Xiangyuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第1期217-228,共12页
The Naruo porphyry copper-gold deposit (hereinafter referred to as the Naruo deposit) in Tibet is a potentially ultra-large, typical gold-rich porphyry copper deposit, which was recently discovered in the Bangongco-... The Naruo porphyry copper-gold deposit (hereinafter referred to as the Naruo deposit) in Tibet is a potentially ultra-large, typical gold-rich porphyry copper deposit, which was recently discovered in the Bangongco-Nujiang metallogenic belt. This study analyzed U-Ph chronology and Hf isotopes of the ore-bearing granodiorite porphyry in the Naruo deposit using the LA-ICPMS dating technique. The results show that the weighted average age is 124.03±0.94Ma (MSWD=1.7, n=20), and 2±6pb/23SU isocbron age is 126.2±2.7 Ma (MSWD=1.02, n=20), both of which are within the error. The weighted average age represents the crystallization age of the granodiorite porphyry, which indicates that the ore-bearing porphyry in the Naruo deposit area was formed in the Early Cretaceous and further implies that the Neo-tethys Ocean had not been closed before 124 Ma under a typical island-arc subduction environment. The εGr(t) of zircons from the granodiorite porphyry varies from 2.14 to 9.07, with an average of 5.18, and all zircons have εRf(t) values greater than 0; 176Hf/177Hf ratio is relatively high (0.282725-0.282986). Combined with the zircon age--Hf isotope correlation diagram, the aforementioned data indicate that the source reservoir might be a region that is mixed with depleted mantle and ancient crust, which possibly contains more materials sourced from depleted mantle. Rock-forming ages and ore-forming ages of the Duolong ore concentrate area are 120-124 Ma and 118-119 Ma, respectively, which indicate 124-118 Ma represents the main rockforming and ore-forming stage within the area. The Naruo deposit is located in the north of the Bangongco-Nujiang suture, and it yielded a zircon LA-ICPMS age of 124.03 Ma. This indicates the Bangongco-Nujiang oceanic basin subducted towards the north at about 124 Ma, and the Neo-tethys Ocean had not been closed before the middle Early Cretaceous. It is possible that the crust-mantle mixing formed the series of large and giant porphyry copper-gold deposits in the Bangongco. 展开更多
关键词 gold-rich porphyry copper deposit ore-bearing porphyry zircon LA-ICPMS dating Hfisotope bangongco-nujiang suture Naruo Tibet
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THE PERMIAN SYSTEM OF THE NUJIANG—LANCANGJIANG—JINSHAJIANG AREA, SOUTHWESTERN CHINA
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作者 Mao Junyi\+1, Zou Guangfu\+2 2. Chengdu Institute of Geology and Mineral Resources, Chengdu 610082, China) 《地学前缘》 EI CAS CSCD 2000年第S1期362-362,共1页
Permian system is one of the best developed systems in Sanjiang area. In Yidun\|Zhongdian and in Zhiso\|Muli, The Lower Permian is clastics\|carbonates\|volcanics with interbeds of siliceous sediments, Whereas the Upp... Permian system is one of the best developed systems in Sanjiang area. In Yidun\|Zhongdian and in Zhiso\|Muli, The Lower Permian is clastics\|carbonates\|volcanics with interbeds of siliceous sediments, Whereas the Upper Permian is composed of lower part of basic volcanics and upper part of clastics\|carbonates with a total thickness of 1000~4000 meters .In Zhongzha (Batang)\|Jingping region, It is mainly carbonates of 217~1320 meters thick, But in Jingping proper, there occur about 5000 meters thick basalts of early late Permian . From Batang to Benzinan along the Jinshajiang river , the lower Permian is clastics\|volcanics\|carbonates formation with interbeds of siliceous sediments and spilite formation; Whereas the Upper Permian is clastics with volcanic interbeds; The total thickness being 3700 to 7100 meters. In Jiangda—Mangco (Mangkang), It is clastic\|carbonate\|volcanic formation of 1100 to 2400 meters . In Tuoba (Qamdo)—Haitong (Mankang)—Ximi (Mujiang ), It is mainly clastics\|carbonates formation , the Upper Permian being coal\|bearing clastics sequence and the total thickness being 700~2500 meters ,In Zhado—Zhasuosuo (Mangkang)—Deqing—Qinggu—Qinghong, It is clastic\|carbonate\|volcanic formation, locally with coal\|bearing clastics of Upper Permian and the total thickness of mainly carbonate formation and clastic formation with coal\|bearing clastic formation of Uppermian, is 800 to 2000 meters. In the whole area , the Permian strata were slightly metamorphosed, locally more intensively metamorphosed up to amphibolite facies. The fossils found belong to fusulinids, coral, brachiopods,ammonite,bivalve, gastropods, bryozoa,foraminifera, trilobite, algae ,porifera (sponge), and continental plant . Besides the Gondwana cold\|water type components of brachiopods found in Baoshan, the fossils belong mainly to Cathaysian biota, especially to South China type. In some places such as Mangkang, Guxue (Dewong), to South China type. In some places such as Mangkang, Guxue (Dewong), and Wachang (Muli), the resedimented Late Carboniferous fusulinid fossils can be found in the clastic limestone of Lower Permian, and the Early Permian or even Middle to Late Carboniferous fusulinid fossils found in Upper Permian classic limestone. All these suggest the resedimentation of biolimestone blocks or fragments related to fault\|volcanism .On the section of Tongba (Muli), the permian is continuous graded upwards into the Triassic, with a transitional zone of fossil. 展开更多
关键词 PERMIAN SEDIMENTARY characteristic REGIONAL STRATIGRAPHY the nujiang—Lancangjiang—Jinshajiang area SOUTHWESTERN China
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