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On Metallogenic Conditions and Regularities of the Lower and Middle Reaches of the Changjiang River

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Acta Geologica Sinica(English Edition) 1988年第4期1卷 435-449页

作者： Liu Xiangpei Chang Yinfo Wu Yenchang anhui Bureau of Geology and Mineral Resources, hefei, anhui anhui Institute of geological sciences, hefei, anhui anhui BUR GEOL & MINERAL RESOURCES HEFEIPEOPLES R CHINA anhui INST GEOL SCI HEFEIPEOPLES R CHINA

The paper deals with the metallogenic conditions and regularities of the region ol the lower-middle reachesof the Changjiang River in China. The complicated structural network with the Changjiang (Yangtse) deepfracture as its trunk is the leading rock-and ore-controlling structure of the metallogenic belt. Thehigh-potassium granodiorites of the first magmatic sequence of the Mesozoic Yangtse syntexis type and thesodium-rich diorites of the second sequence are genetically related to the copper ore series and the iron ore se-ries respectively. and occur respectively in the block-faulted and-folded uplift area and the down-faulted vol-canic basin as well as the transitional zone between the two. The ore-hosting horizons show specific associa-tions of rocks and often contain ore beds basically of stratabound nature.

关键词： Cu In On Metallogenic Conditions and Regularities of the Lower and Middle Reaches of the Changjiang River

^(40)Ar/^(3.)Ar dating of shear deformation of the Xianshuihe fault zone in west Sichuan and its tectonic significance

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Science China Earth sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2. 3.& YANG Nong1 1. Institute of Geomechanics, Chinese Academy of geological {2., Beijing 100081, China 2. Institute of Geology, Chinese Academy of geological {2., Beijing 10003., China 3. Institute of Geology and Geophysics, Chinese Academy of {2., Beijing 10002., China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12.10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 3.0℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/3.Ar dating, late Cenozoic.

Tectonic Framework and Evolution of the Dabie Mountains in anhui, Eastern China

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 221-238,326页

作者： Xu Shutong Jiang Laili Liu Yican Zhang Yong Institute of geological sciences of {2. Province, {3., {2. Sun Sheping Institute of geological sciences of {2. Province Hefei Anhui

The Dabie Mountains are believed to be a collisional orogenic belt between the Yangtze amd Sino-Koreancontinental plates. It is composed of the foreland fold-thrust zone, the subducting cover and basement of theYangtze continental plate, the coesite- and diamond-bearing ultra-high pressure metamorphic zone and themeta-ophiolitic melange zone in the subducting basement, the fore-arc flysch nappe and the back thrust zoneoccurring respectively on the southern and northern margins of the Sino-Korean continental plate and the in-herited basin with molassic deposits on the northern margin. When the palaeo-Dabie oceanic plate subductednorthward in the Early Palaeozoic, volcanic arc and back arc basin probably formed on the southern margin ofthe Sino-Korean continental plate. The Sm / Nd isotopic dating of the strata and eclogite which were drawn in-to the foreland fold-thrust zone indicates that the intense collision of the two continental plates took place inthe Early Mesozoic.

关键词： collisional orogenic belt ultra-high pressure metamorphic zone ophiolitic melange zone coesite diamond

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.

The effects of K^+ growth conditions on the accumulation of cesium by the bacterium Thermus sp. TibetanG6

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Science China(Life sciences) 2006年第2期49卷 123-129页

作者： WANG Hailei1,2.3. KONG Fanjing1,2.3.& ZHENG Mianping1,2.3.1. R&D Center for Saline Lake and Epithermal Deposits, Chinese Academy of geological sciences, Beijing 10003., China 2. Key Open Laboratory of Saline Lake Resources and Environment, Chinese Academy of geological sciences, Beijing 10003., China 3. Institute of Mineral Resources, Chinese Academy of geological sciences, Beijing 10003., China R&D Center for Saline Lake Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China Key Open Laboratory of Saline Lake Resources Environment Chinese Academy of Geological Sciences Beijing 100037 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

The accumulation of cesium by the bacterium Thermus sp. TibetanG6 was examined under different K+ growth conditions. The effects of external pH and Na+ on the accumulation of ce-sium were also studied, and the mechanism involved was discussed. K+ regimes played an important role in the accumulation of cesium by the strain TibetanG6. The quantity of cesium accumulated (2. h) was much higher in K+-deficient regime than that in K+-sufficient regime. The pH and Na+ had different effects on the accumulation of cesium in the two K+ regimes. IR spectra analyses indicated that the biosorption is a process of homeostasis with cesium initially accumulated on the cell wall.

关键词： Thermus sp. TibetanG6, cesium, bioaccumulation, K+-growth condition, pH, sodium, IR spectroscopy.

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science China Earth sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2. DU Andao1, LU Jiren3. QU Wenjun1 & CHEN Jiangfeng2.1. National Research Center of Geoanalysis, Beijing 10003., China 2. Laboratory for Earth Material Cycling, School of Earth and Space {2., University of Science and Technology of China, hefei 2.0}02., China 3. Institute of Mineral Resource, Chinese Academy of geological {2., Beijing 10003., China National Research Center of Geoanalysis Beijing China Laboratory for Earth Material Cycling School of Earth and Space Sciences University of Science and Technology of China Hefei China Institute of Mineral Resource Chinese Academy of geological sciences Beijing China

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 83. ± 3. Ma, initial 187Os/188Os ratio of 0.2.9 ± 0.018 (MSWD = 1.7) and γOs = 13. ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous SHRIMP zircon U-Pb age of 82. ± 8 Ma (n=5, MSWD = 4.3.. The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

A Preliminary Research on Skarns of Magmatic Origin

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Journal of Earth Science 1999年第1期18卷 58-61页

作者： Wu Yanchang anhui Institute of geological {2.,{3.

Skarns of magmatic origin, or magmatic skarns as called, are formed by crystallization of skarnic magma injecting into structural fissures. They occur in various rocks (rock formations), mainly in form of veins. Usually, they possess massive structure and cumulative texture. They mainly consist of calc silicate, without or with minor water bearing silicates. The typical minerals in it include alkali feldspar, calcite and anhydrite. Some silicate melt inclusions and high temperature, high salinity poly phase inclusions can be seen in the crystals of their host minerals. The particular members of the magmatic skarns are transitional skarn and skarnic pegmatite. The magmatic skarn and the congenetic alkali rich diorite usually collaborate in a conjugating and complementary manner. They probably are the products of calcic contamination, degassing, desilicification and separation in melt state of deep seated (high level magma chamber) alkali rich intermediate acid magma.

关键词： magmatic skarn magmatic skarn alkali intrusive pair the middle and lower reaches of Changjiang River.

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 Bureau of Geology and Mineral Resources, Jingzhou 43.100, China 3. geological Survey of Jiangxi Province, Nanchang 3.02.1, China China Univ Geosci Sch Earth Sci Wuhan 430074 Peoples R China Hubei Bur Geol & Mineral Resources Hydrogeol Team Jinzhou 434100 Peoples R China Geol Survey Jiangxi Province Nanchang 3300201 Peoples R 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.

Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,China

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Chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of sciences, Beijing 100044, China 2. College of Earth sciences and Resources, China University of Geo-sciences, Beijing 100083. China 3. Department of {3. sciences, Southern Methodist University, Dallas, TX 752.5, USA Institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.