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Science China Earth Sciences 2006年第6期49卷 597-603页

作者： XIE Yuling1, HOU Zengqian2. XU Jiuhua1, YUAN Zhongxin2. BAI Ge2.& LI Xiaoyu3.1. Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083. China 2. Institute of Geology, Chinese Academy of {2. Sciences, Beijing 10003., China 3. the 109th geological team,{2.,{3., China Civil and Environmental Engineering School University of Science and Technology Beijing Beijing China Institute of Geology Chinese Academy of Geological Sciences Beijing China the 109th {2. {2. Sichuan Bureau of Mineral Exploration Chengdu China

Mianning-Dechang Himalayan REE Metallogenetic Belt in sichuan Province lies along the western margin of the Yangtze Craton. We have conducted detailed mineralogical studies on ore minerals collected from Maoniuping and Dalucao, the two largest deposits in the belt. With optical microscope, SEM/EDS, and EPMA, three rare intermetallic minerals, i.e., zinccopperite (Cu2.n), Sn- bearing native copper, and Cu-bearing jupiter were found to occur in the main ore along with barite, fluorite, apatite, sulfide and bastnaesite. Since the conditions under which zinccopperite and Sn- bearing native copper formed are quite unique, finding of these minerals, for the first time in domestic REE deposits, has significant implications for the genesis of the ore deposits in which they occur. In comparison with Cu-Zn intermetallic minerals in other occurrences, we propose that the formation of this REE metallogenetic belt is associated with fast upwelling of the Himalayan magma from deep source.

关键词： Mianning-Dechang REE metallogenetic belt, Cu-bearing intermetallic minerals, EPMA, genesis significance, deep source magmatic activity.

On the siltation of the middle Yangtze River

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Science China Earth Sciences 2004年第5期47卷 463-480页

作者： YIN Hongfu1, CHEN Guojin2. LI Chang抋n1 & WEI Yuan3.1. School of Earth Sciences, China University of Geosciences, Wuhan 43.074, China 2. Hydrogeological team, Hubei {2. of Geology and {3. Resources, Jingzhou 43.100, China 3. geological Survey of Jiangxi Province, Nanchang 3.02.1, China School of Earth Sciences China University of Geosciences Wuhan 430074 China Hydrogeological team Hubei Bureau of Geol./Mineral Rsrc. Jingzhou 434100 China geological Survey of Jiangxi Prov. Nanchang 330201 China

About 5.2.108 t/a of silts from the upper reach of the Yangtze River are transported through Yichang into the middle Yangtze River. the middle Yangtze itself and its tributaries yield ca. 0.8×108 t silts annually. Of this total 6×108 t/a input of silts, ca. 1.2.108 t/a are deposited within the river artery and lakes, while ca 4.83.108 t/a are at first transported into the lower reach through Datong, and then either deposited along the river and the Yangtze Delta, or output into the sea. Along the middle Yangtze River silting generally exceeds scouring, but the spatial and temporal distributions of scour-and-fill, as well as its distribution in the river valley transections, are uneven. Along the Yichang-Chenglingji and Jiujiang-Datong Segments of the middle Yangtze, scouring exceeds or equals silting. Silting mainly occurs along the Luoshan-Wuhan-Huangshi Segments with Wuhan as the pivotal point, as well as in the Dongting and Poyang Lakes. Even in these silting-dominated areas, there are times and parts of segments that scouring prevails. As to the transections, generally the river channel of main stream is scouring-dominated, forming V-shaped sections to a depth of 2.3. m or more, whereas the floodplains and bar islands are silting-dominated, forming wide and relatively high flats, which are often artificially transformed into protected embankments. Because the Jingjiang Levee separates the Jianghan Plain from Yangtze to the south, little has been deposited in that plain except a few sediments from the Han River—a tributary of the middle Yangtze. this factor plus the tectonic sag of that plain has made the altitude of plain surface several meters lower than that of the levee in most of the areas. Sil-tation along the Luoshan-Wuhan-Huangshi Segments has resulted in the elevation of flood level in this and upstream segments. River channel scouring plus floodplain silting have caused the transections of the middle Yangtze valley typically with deep channel and height

关键词： the middle Yangtze, scour-and-fill, siltation, silt utilization.

Aoyitake plagiogranite in western Tarim Block, NW China: Age, geochemistry, petrogenesis and its tectonic implications

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Science China Earth Sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2. YU Haifeng3. YE Haimin2. ZHAO Yu2.& ZHANG Dongsheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2. Nanjing Institute of Geology and mineral Resources, Nanjing 2.0016, China 3. Tianjin Institute of Geology and mineral Resources, Tianjin 3.0170, China 4. the 2.d Regional {2. Investigation Party, Xinjiang {3. of Geology and mineral Resources, Changji 83.100, China Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Nanjing Institute of Geology and mineral Resources Nanjing China Tianjin Institute of Geology and mineral Resources Tianjin China the 2.d Regional geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW China. the plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2 and crystallized at 3.0.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. the granites are sodic with Na/K ratios (molar) between 4 and 87. Total REE (50-220 ppm) show a clear positive correlation with SiO2. there is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3.0.6), high Y content and low Sr/Y ratio (~1.0). these granites exhibit relatively juvenile Nd T2DM model ages of 470 to 580 Ma and positive εNd(3.1 Ma) values of 6.23.to 7.65. the aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. the primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.

Zhang-Xuan thermal uplift and its genesis

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Progress in Natural Science:Materials International 2005年第8期15卷 725-732页

作者： SHAO Ji'an1*, NIU Shuyin2. ZHANG Lüqiao3.and LI Hongyang2.1. School of Earth and Space Sciences, Peking University, Beijing 100871, China 2. Shijiazhuang University of Economics, Shijiazhuang 05003., China 3. geological bureau of Inner Mongolia, Huhhot 01002., China) School of Earth and Space Sciences Peking University Beijing 100871 China. Shijiazhuang University of Economics Shijiazhuang 050031 China. geological bureau of Inner Mongolia Huhhot 010020 China

Based on the researches of the Mesozoic thermal evolution history, the deformed structures, and fission track analysis of the Zhangjiakou-Xuanhua area, we obtained the following knowledge: the area experienced in 140 Ma an underplating which is marked by emplacement of mantle derived magma; during 13.—110 Ma a series of eruptions and intrusions happened, and during 80—10 Ma a rising process occurred which is synchronous with the adjacent Taihang and Yanshan Mountains and was accompanied by a series of structures down slipping from the just formed Zhang-Xuan uplift toward its periphery. Combining the Zhang-Xuan thermal lift with the large detachment structure in Baoding depression of the North China Basin in the Late Mesozoic confirms that an even larger extensional tectonic background existed in North China during this period.

关键词： Zhang-Xuan area underplating thermal uplift fission track extensional structure.

Discovery of Fossil Charophytes from the Late Triassic Xujiahe Formation and Early Jurassic Lower Yimen Formation, sichuan Province, and Its Significance

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 301-309,327页

作者： Liu Junying Chen Zhongliang Institute of Geology, Chinese Academy of geological Sciences, Beijing Panxi geological Party, {2. {3. of Geology and mineral Resources, Xichang Liu Linqun Institute of Geology Chinese Academy of Geological Sciences Beijing China

this paper describes the fossil charophytes collected from the Late Triassic Xujiahe Formation in Dazuand Early Jurassic Lower Yimen Formation in Xichang, sichuan Province, and their significance. Up to now,papers dealing with fossil charophytes of the Late Triassic, especially of the Early Jurassic, have been rarelypublished. the description of the two new species of Porochara, P. dazuensis and P. xichangensis, and theirfossil assemblage not only provides an important basis for classification and correlation of red beds insouthwestern China but reveals for the first time the features of the charophyte flora of the Late Triassic-EarlyJurassic in the area, thus offering valuable data for the establishment of Triassic and Jurassic charophyte fossilzones in China.

关键词： sichuan Late Triassic Early Jurassic charophyte fossil

Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu {2.ization

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Science China Earth Sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1, QU Xiaoming1, WANG Shuxian2. DU Andao2. GAO Yongfeng3.& HUANG Wei4 1. Institute of mineral Resources, Chinese Academy of {2. Sciences, Beijing 10003., China 2. National Center of Geoanalysis, Chinese Academy of {2. Sciences, Beijing 10003., China 3. Shijiazhuang College of Economy, Shijiazhuang 056000, China 4. Xizang {3. of Geology and mineral Resources, Lhasa 850000, China Institute of mineral Resources Chinese Academy of Geological Sci. Beijing 100037 China National Center of Geoanalysis Chinese Academy of Geological Sci. Beijing 100037 China Shijiazhuang College of Economy Shijiazhuang 056000 China Xizang bureau of Geol./mineral Rsrc. Lhasa 850000 China

the Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. the belt trends {2.0 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (1{2.18 Ma). the timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.2.) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 1{2.5 Ma to 1{2.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.{2.?.2.) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. the emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 2.—2.2.Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

mineralogy and Mode of Occurrence of Gold, Silver and Bismuth of the Caijiaying Lead-Zine-Silver Deposit, Hebei Province

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 371-385,461页

作者： Huang Dianhao Ding Xiaoshi Wu Chengyu Zhang Changjiang Institute of mineral Deposits, Chinese Academy of geological Sciences, Beijing geological Party No.3. Hebei {3. of Geology and mineral Resources, Zhang jiakou, Hebei Fei Zhenbi Institute of mineral Deposits Chinese Academy of Geological Sciences Beijing China

the deposit under study is a hydrothermal filling-metasomatic vein type lead-zinc-silver deposit, in whichgold and silver can be recovered as by-products. these metals mainly occur as microgranular native gold,electrum, stephanite, acanthite, pyraragyrite, freibergite, and native silver. Gold minerals tend to be associatedwith galenobismutite, native bismuth and unnamed Bi_2.e. they are either enclosed in pyrite, marmatite,iron-bearing sphalerite and galens or fill the microfissures of these minerals. Silver minerals usually occur incleavages or fissures of galena, marmatite and pyrite, but are not associated with gold and bismuth minerals.Gold and silver mineralizations occurred later than lead and zinc, while the silver mineralization was precededby that of gold.

关键词： mineralogy and Mode of Occurrence of Gold Hebei Province

Crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science China Earth Sciences 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2. TENG Jiwen1, Lü Qingtian3. LI Jiliang1, SUN Shanxue1 & WANG Xinzheng1 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 2. Institute of Geophysics, Chinese Seismological bureau, Beijing 100081, China 3. Institute of Deposition Resource, Chinese Academy of geological Sciences, Beijing 10003., China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Institute of Geophysics Chinese Seismological Bureau Beijing China Institute of Deposition Resource Chinese Academy of Geological Sciences Beijing China

the wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. the crustal reflections in the Yangtze block are very well developed. the crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. the average thickness of the crust in the studied area is about 40 km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.

关键词： Gondwana blocks,Yangtze blocks,wide-angle profile,crustal structure,tectonic setting

the Geochemical Characteristics and Minerogenic Model for the Amo Hypothermal Tin Deposit in Ximeng County, Yunnan Province

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 271-287页

作者： Zhao Daxian Tang Guangting the Fifth {2. Party, Yunnan bureau of Geology and {2. Resources, Simao,Yunnan Liu Linqun the Fifth {2. Party Yunnan Bureau of Geology and Mineral Resources Sirnao Yunnan

through studies on the element geochemistry, alteration of country rocks, ore-forming fluids and isotopegeochemistry of the Arno tin deposit in the metamorphic rocks of the Upper Proterozoic Ximeng Group, theauthors consider that the concentration of the B-F-Li-Rb-Cs-Sn association is related to acidic magmatism inthe study area. the Fe-Mg-Li tourmaline in the ore is the replaced product of the country rocks byhypothermal fluid. the δ^(18)O values of mineral separates are +2.01- +13.16‰ and their δ^(3.)S values, +2.6-+7.2.. the ore-forming materials were derived from hydrothermal fluid of granitic magma. For themineralization, the temperature is 450°-3.0℃, the pressure, 450-1000×10~5 Pa, and the age, Himalayan(2..5 Ma). According to the geochemical characteristics, a minerogenic model is established: the deposit is ahypothermal cassiterite-quartz vein type tin deposit controlled by the hidden Himalayan granites.

关键词： the Geochemical Characteristics and Minerogenic Model for the Amo Hypothermal Tin Deposit in Ximeng County Yunnan Province

REE Geochemistry in the Weathered Crust of Granites, Longnan Area,Jiangxi Province

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Acta Geologica Sinica(English Edition) 1990年第2期64卷 193-209,237页

作者： Wu Chengyu Huang Dianhao Guo Zhongxun Institute of mineral Deposits, Chinese Academy of geological Sciences, Beijing geological Survey Party of South Jiangxi, Jiangxi {3. of Geology and mineral Resources, Ganzhou, Jiangxi Chinese Academy of geological Sciences Beijing China

Warm and humid climate and gentle hilly topography have provided favourable conditions for the devel-opment of the weathering crust of the granite intrusions in the Longnan area, Jiangxi Province. REE is mostlyconcentrated in an adsorption state in clay in the wholly weathered zone. the rare-earth minerals enriched inthe parent rocks provided the source material for the REE enrichment. Exchangeable REE accounts for48-86%. Extraction experiments and stable isotopic study of clay minerals suggest that the downward infiltra-tion of meteoric water and increasing gradient of pH values have played an important role in the enrichment ofREE during the progressive weathering. Slight fractionation of individual REE can not change their distribu-tion patterns in the profiles. which are inherited from the parent rocks.

关键词： REE Geochemistry in the Weathered Crust of Granites Longnan Area,Jiangxi Province