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Petrology of the Non-mafic UHP Metamorphic Rocks from a Drillhole in the Southern Sulu Orogenic Belt,Eastern-Central china

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Acta Geologica Sinica(English Edition) 2003年第2期77卷 173-186页

作者： ZHANG Zeming, XU Zhiqin and XU Huifeninstitute of Geology, chinese academy of {3. Sciences, 26 Baiwanzhuang Rd.,{4. E-mail: zzm@***. institute of Geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Rd. Beijing 100037

The Drillhole ZK703.with a depth of 558 m is located in the Donghai area of the southern Sulu ultrahigh-pressure (UHP) metamorphic belt, eastern china, and penetrates typical UHP eclogites and various non-mafic rocks, including peridotite, gneiss, schist and quartzite. Their protoliths include ultramafic, mafic, intermediate, intermediate-acidic, acidic igneous rocks and sediments. These rocks are intimately interlayered, which are meters to millimeters thick with sharp and nontectonic contacts, suggesting in-situ metamorphism under UHP eclogite facies conditions. The following petrologic features indicate that the non-mafic rocks have experienced early-stage UHP metamorphism together with the eclogites: (1) phengite relics in gneisses and schists contain a high content of Si, up to 3.52 p.f.u. (per formula unit), while amphibolite-facies phengites have considerably low Si content (3.26 p.f.u.); (2) jadeite relics are found in quartzite and jadeitite; (3. various types of symplectitic coronas and pseud

关键词： UHP metamorphism non-mafic rock drillhole Dabie-Sulu orogenic belt eastern-central china

SUSPENDED SEDIMENT TRANSPORT IN THE OFFSHORE NEAR YANGTZE ESTUARY

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Journal of Hydrodynamics 2008年第3期20卷 373-381页

作者： CHEN Bin WANG Kai institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate University of the chinese academy of Sciences Beijing 100039 China

Based on the Estuarine, Coastal and Ocean Modeling System with Sediments （ECOMSED） model, a 3.D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East china Sea .The hydrodynamic module was driven by tide and wind. Sediment module included sediment resuspension, transport and deposition of cohesive and non-cohesive sediment. The settling of cohesive sediment in the water column was modeled as a fimction of aggregation （flocculation） and deposition. The numerical results were compared with observation data for August, 2006. It shows that the sediment concentration reduces gradually from the seashore to the offshore area. Numerical results of concentration time series in the observation stations show two peaks and two valleys, according with the observation data. It is mainly affected by tidal current. The suspended sediment concentration is related to the tidal current during a tidal cycle, and the maximum concentration appears 1 h-4.h after the current maximum velocity has reached.

关键词： Yangtze Estuary sediment concentration sediment transport

Geochronology of Yanshanian Magmatism and Metamorphism in the Hinterland of the Dabie Mountains and Their Geologic Implications

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Acta Geologica Sinica(English Edition) 1992年第2期66卷 155-163,222页

作者： Chen Tingyu Niu Baogui Liu Zhigang Fu Yunlian Ren Jishun institute of Geology, chinese academy of {3. Sciences, {4. institute of Geology Chinese Academy of Geological Sciences Beijing

A strong tectono-magmatic thermal event has been revealed by field observations of granitic, migmatiticand metamorphic rocks in the hinterland of the Dabie Mountains. K-Ar, Ar-Ar and Rb-Sr determinationsshow that the event took place 13.-117 Ma ago (Yanshanian). Contemporaneously, a southwestwardthrust-type ductile shearing at multiple levels occurred in the lower crust or at even deeper levels, suggestingthat the Dabie Mountains region was still under the influence ot strong continent-continent overlappingtectonism of the Yangtze block under the Sino-Korean block at depth. Metamorphic rocks of amphibolitefacies, migmatites and deep structural deformations resulting from this tectonothermal event are now exposedto the surface. The present features of the Dabie Mountains thus have appeared only since ca. 100 Ma B.P. Theblock composed of the Dabie Group is not an uplift or shield which would have undergone a long-continuederosion.

关键词： Geochronology of Yanshanian Magmatism and Metamorphism in the Hinterland of the Dabie Mountains and Their Geologic Implications

Late Eocene Sporopollen and Paleoclimate, Paleoenvironment of the Yuanqu Basin, Shanxi

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Continental Dynamics 1999年第2期 29-38页

作者： WANG Daning (institute Of Geology,chinese academy of {3. Sciences,{4.,china)

The Late Eocene sporopollen of the Yuanqu Basin in Shanxi Province has been studied, and four sporopollen assemblages are established, in which two of them are mainly composed of pollen of angiosperm and gymnosperm, the third is mainly composed of spores of pteridophyte, and the last is of fresh water algae *** on the character of the palynoflora, the Late Eocene flora, paleoclimate and paleoenviroment of the Yuanqu Basin are discussed. This Late Eocene flora belongs to the transitional flora from temperate zone to tropical zone (transitional floral region from Portawa Floral Realm and Durgai Floral Realm). The character of paleoclimate in Late Eocene of this region is from a teinperate and humid subtropical to mild temperate zone climate. The global temperature declining event has a certain reflection in this region. The oscillation of arid climate occurs as well. During Late Eocene, lakes and marshes widely distributed in this region, and further more, the lakes and marshes frequently alternated with dry lands, appearing 3.or more times.

关键词： Late Eocene paleoclimate paleoenvironment paleoflora

Tectono－Stratigraphic　Units　of　Western　Yunnan，　china　and　Their　Counterparts　in　Southeast　Asia

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Continental Dynamics 1996年第2期 123-133页

作者： Jin Xiaochi(institute of Geology ,chinese academy of {3. Sciences,{4., china)

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关键词： tectono-stratigraphic unit western Yunnan Southeast Asia

Occurrences of Permian radiolarians in central and eastern Nei Mongol(Inner Mongolia) and their geological significance to the Northern china Orogen

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chinese Science Bulletin 2004年第24期49卷 2613-2619页

作者： SHANG Qinghua Nanjing institute of Geology and Paleontology,chinese academy of Sciences,Nanjing 210008,{3. institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of Sciences,beijing 10004.,{3. Nanjing institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

The Zhesi (Jisu) Formation of the Middle Per- mian in Nei Mongol (Inner Mongolia) was commonly con- sidered to be a shallow marine sequence. Here I report the radiolarians found in the argillite bed of that formation in Zhesi and Xilinhot areas. This fact indicates a deep marine sedimentary facies persisted during the Middle Permian, and suggests that the ocean between the North china Block and Siberian Craton was not closed until the Late Guadalupian. The suture of this two blocks is probably extends along the Linxi ophiolite belt, south of the Hegenshan ophiolite belt.

关键词：造山带地质意义内蒙古放射虫二叠纪

^(13.)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

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Pedosphere 2011年第1期21卷 37-45页

作者： LI Hao ZHANG Xin-Bao WANG Kc-Lin WEN An-Bang institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 (China) Graduate University Chinese Academy of Sciences Beijing 100049 (China) State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-13.(13. Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 13. Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 13. Cs redistribution in a karst area of Southwest *** results indicated that the 13. Cs inventories of the surface soil on the slope studied were much lower than that of the local 13. Cs reference inventory and the 13. Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 13. Cs inventories was characterized by considerable *** high 13. Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 13. Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 13. *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 13. Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^13.Cs fallout, ^13.Cs inventory karst area runoff

Important Events and Chronological Framework of the Early Precambrian Granulite Terrain,Northwestern Hebei Province

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 466-479页

作者： Geng Yuansheng, Liu Dunyi and Song Biaoinstitute of Geology, chinese academy of {3. Sciences, 26 Baiwanzhuang,{4. 100037, china institute of Geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Beijing 100037 China [?]Geng Yuansheng Born in January 1950 got a master degree at the Changchun College of Geology in 1981 long engaged in the study of Early Precambrian geology and metamorphic petrology now research professor at the institute of Geology Chinese Academy of Geological Sciences.

Based on the chronological data and relevant geological evidence, the chronological framework of the major geological events of the granulite terrain in northwestern Hebei Province and its adjacent areas has been established. Basic lava eruption occurred in the span of 2868-293. Ma, resulting in the formation of the early crust. The TTG magma emplacement took place c.2761 Ma ago. Subsequently basic magma intruded into the supracrustal rocks at 2650 Ma, resulting in crustal thickening. The thickening was enhanced at 2561-2503.Ma by the widespread intrusions of granodioritic magma. In the period of 24.7-24.1 Ma charnockite intruded, accompanied by regional granulite facies metamorphism. The second stage of granulite facies metamorphism occurred c. 23.0 Ma ago, and finally pink granite intrusions at 214.-2087 Ma resulted in the formation of a granite zone.

关键词： geological event Early Precambrian geochronology granulite northwestern Hebei

Kinetics of ore-forming fluids in epithermal systems

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chinese Science Bulletin 1999年第S2期44卷 5-6页

作者： ZHANG Ronghua, ZHANG Xuetong and HU Shumin Open Research Laboratory of Geochemical Kinetics, institute of Mineral Deposits, chinese academy of {3. Sciences,{4., china Open Research Laboratory of Geochemical Kinetics Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China

As verified by the data of fluid inclusions in minerals in some paleo-hydrothermal systems, a lowering intemperature of the ore-forming fluids and a decrease in salinity occurred simultaneously from the centralzone （deep part） of the deposit profile to its outer zone （shallow part）. The usual situation shown byexperimental data is that solubility rises with an increase in temperature, as shown by quartz and manyore minerals. However, the solubility of some minerals increases as the temperature decreases within acertain temperature range. Therefore, continuous deposition cannot be achieved as the temperature of thesystem decreases, as in the cases of calcite, fluorite, and anhydrite. In water and NaCl-H2O systems,the solubility of calcite （or anhydrite） decreases with a rise in temperature at 3.0℃ (or 4.0℃

关键词： kinetics ore-forming fluids epithermal systems.