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processes and environmental significance of the subglacial chemical deposits in Tianshan Mountains

Science china earth {2. 2005年第9期 144-152页

作者： LIU Gengnian, LUO Risheng, CAO Jun & CUI Zhijiu college of environmental {2.,{3., Beijing 100871, china

On the bedrock surface of Glacier No.1 in the headwater of Urumqi River, Tianshan Mts., well layered and crystallized subglacial calcite precipitations were discovered. Based on observations and analysis of the surface form, sedimentary texture and structure, and chemical composition of the deposits, clues about the subglacial {2. and environment are deduced. The radial-growth crustation texture of the deposits, which builds up in the saturated CaCO3.so- lution, proves the existence of pressure melting water and water films under Glacier No.1; and their rhythmic beddings, dissolved planes and unconformable contacts show that the water films responsible for the formation of these structures were in a wide range of spatial as well as tem- poral variations. Though formed under continental glacier in non-limestone area, the deposits are quite similar to those formed under temperate glaciers in limestone areas, a fact that shows a similar process of chemical precipitation between the two. Hence the enrichment of calcium in the subglacial melting water and the process of precipitation have actually little to do with the bedrock lithology and the glacier types. The cemented detritus in the deposits are rich in Fe and Al while depleted in K, Na and Si; also the included clay mineral consists mainly of illite, which reveals some weak chemical weathering under the continental glacier. The subglacial CaCO3.precipitates when plenty of Ca++ melt into the subglacial melting water on a comparatively en- closed ice-bedrock interface under a high CO2.partial pressure, the forming of subglacial chemical deposits therefore offers unequivocal evidence for the ongoing of subglacial chemical reactions.

关键词： subglacial processes chemical deposits continental glacier.

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Analysis of sea surface temperature fronts in the Taiwan Strait and its adjacent area using an advanced edge detection method

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Science china earth {2. 2010年第7期53卷 1008-1016页

作者： PI QingLing1,2.3.& HU JianYu1,2.1 State Key Laboratory of Marine environmental Science, Xiamen {3., Xiamen 3.1005,{2. 2.Department of Oceanography, Xiamen {3., Xiamen 3.1005,{2. 3.2. Communications Construction Company First Harbor Consultants CO., LTD., Tianjin 3.02.2.{2. 1. State Key Laboratory of Marine environmental Science Xiamen University Xiamen 361005 China2. Department of Oceanography Xiamen University Xiamen 361005 China3. China Communications Construction Company First Harbor Consultants CO. LTD. Tianjin 300222 China

A morphology-based edge detection method has been used to study sea surface temperature (SST) fronts in the Taiwan Strait and its adjacent area. The method is based on mathematical morphology with multi-dimensional and multi-structural elements. Using six years’ SST data from September 2.02.to August 2.08, we distinguished the large SST front like Kuroshio Front as well as the smaller ones: namely Taiwan Bank Front, Zhe-Min Coastal Front and Zhang-Yun Ridge Front. The seasonal and monthly variations of these fronts were also studied. Generally, the SST fronts are stronger in winter but weaker in summer. And the fronts are at their active stage during the period from January to May but at their declining stage during the period from July to October.

关键词： SST front remote sensing edge detection Taiwan Strait Kuroshio

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Late Cenozoic high-resolution magnetostratigraphy in the Kunlun Pass Basin and its implications for the uplift of the northern Tibetan Plateau

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Science Bulletin 2005年第17期 98-108页

作者： SONG Chunhui1, GAO Dongling1,2. FANG Xiaomin3.1, CUI Zhijiu4, LI Jijun1, YANG Shengli3. JIN Hongbo1, Douglas Burbank5 & Joseph L. Kirschvink6 1. moe Key Laboratory of Western china’s {2. Systems (Lanzhou university), Ministry of Education & college of earth and Environment sciences, Lanzhou university, Lanzhou 73.000, china 2. Qinghai Institute of Salt Lakes, Chinese Academy of sciences, Qing-hai 810008, china 3. Institute of Tibetan Plateau Research, Chinese Academy of sciences, Beijing 100085, china 4. college of {2. sciences, peking university, Beijing 100871, china 5. Department of Geological sciences, university of California, Santa Barbara, USA 6. Paleomagnetics Laboratory, Division of Geological and Planetary sciences, California Institute of Technology, Pasadena, CA 9112., USA

The Kunlun Pass Basin, located in the middle of the eastern Kunlun Mountains, received relatively con-tinuous late Cenozoic sediments from the surrounding mountains, archiving great information to understand the deformation and uplift histories of the northern Tibetan Pla-teau. The Kunlun-Yellow River Movement, identified from the tectonomorphologic and sedimentary evolution of the Kunlun Pass Basin by Cui Zhijiu et al. （1997, 1998）, is roughly coincident with many important global and Plateau climatic and environmental events, becoming a crucial time interval to understand tectonic-climatic interactions. How-ever, the ages used to constrict the events remain great un-certainty. Here, we present the results of detailed magneto-stratigraphy of the late Cenozoic sediments in the Kunlun Pass Basin, which show the basin sediments were formed between about 3.6 Ma and 0.5 Ma and the Kunlun-Yellow River Movement occurred at 1.2.to0.78 Ma. The lithology, sedimentary facies and lithofacies associations divide the basin into five stages of tectonosedimentary evolution, indi-cating the northern Tibetan Plateau having experienced five episodes of tectonic uplifts at3.6, 2.69-2.58, 1.77, 1.2. 0.87 and0.78 Ma since the Pliocene.

关键词： magnetostratigraphy Kunlun Pass Basin Late Cenozoic Tibetan Plateau.

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Bathynotus:A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2.and Cambrian Series 3

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Progress in Natural Science:Materials International 2009年第1期19卷 99-105页

作者： Jin Peng a,b,Yuanlong Zhao b,Jinliang Yuan c,Lu Yao b,Hong Yang b a Department of earth sciences,Nanjing {2.,Nanjing 2.0093.china b college of Resource and environmental Engineering,Guizhou {2.(Caijiaguan Campus),Guiyang 550003.china c Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 2.0008,china [a]Department of earth sciences Nanjing University Nanjing 210093 China [b]College of Resource and Environmental Engineering Guizhou University (Caijiaguan Campus) Guiyang 550003 China [c]Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed ***,its 12.h and 13.h pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural *** genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South china,the Tarim Basin of china,and *** occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early ***,we recognize three species of Bathynotus from china,including *** which is widespread around the *** six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are *** exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2.and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2.and Cambrian Series *** late appearance datum(LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2.and Cambrian Series 3.

关键词： Bathynotus Age Cambrian Series 2 Boundary Correlation

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Distribution and origin of biologically available phosphorus in the water of the Meiliang Bay in summer

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Science china earth {2. 2006年第z1期49卷 146-153页

作者： HUANG Qinghui, WANG Zijian, WANG Donghong, MA Mei & WANG Chunxia State Key Laboratory of environmental Aquatic Chemistry, Research Center for Eco-environmental {2., Chinese Academy of {2., Beijing 100085, china Key Laboratory of Yangtze Aquatic Environment (Ministry of Education), college of environmental Science and Engineering, Tongji university, Shanghai 2.0092. china Chinese Acad Sci Ecoenvironm Sci Res Ctr State Key Lab Environm Aquat Chem Beijing 100085 Peoples R China Tongji Univ Coll Environm Sci & Engn Minist Educ Key Lab Yangtze Aquat Environm Shanghai 200092 Peoples R China

The investigation and continuous monitoring with an innovative iron oxide embedded cellulose acetate membrane (FeO/CAM) on the concentrations of biologically available phosphorus (BAP) were conducted in the Meiliang Bay of the Taihu Lake during summer in 2.04. The results showed that the concentrations of dissolved (FeO-DP), particulate (FeO-PP) and total bioavailable phosphorus (FeO-P) had similar horizontal distribution. The BAP concentrations were the highest in those estuaries in the northern bay. With the decrease of the distance to the estuary or long shore,there was little difference between BAP concentrations in an open lake area. During the observation period, algal blooms occurred in most waters of the northern bay, which was reflected from the high concentrations of chlorophyll a (Chl-a). While they were not highest in the estuarine waters of those major rivers, this is the case for the BAP concentrations. The concentrations of Chl-a had a significantly positive correlation with those of bioavailable phosphorus in the open area of the Meiliang *** the sediment resuspension induced by wind and wave, BAP concentrations increased in a short-term, indicating that the riverine P inputs mainly contribute to the concentrations of BAP in the estuarine water while internal P release was the major source of BAP in the open lake area. In the eutrophic shallow lake, the blooms of alga may cause pH increase and further result in internal P release. The above results showed that the new membrane of FeO/CAM can be used to monitor the concentrations of BAP and provide the scientific justifications for the control strategy of the lake eutrophication.

关键词： phosphorus, bioavailability, eutrophication, resuspension, Taihu Lake.

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Model calculating annual mean atmospheric dispersion factor for coastal site of nuclear power plant

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Journal of environmental sciences 2001年第3期13卷 280-290页

作者： HU Er bang 1, CHEN Jia yi 2. YAO Ren tai 1, ZHANG Mao shuan 1, GAO Zhan rong 1, WANG Shu xian 1, JIA Pei rong 3. Liao Qi lin 4(1 china Institute for Radiation Protection, Taiyuan 03.006,china. 2.Beijing {2., Beijing\ 100871 china Institute for Radiation Protection Taiyuan 030006 China.

This paper describes an atmospheric dispersion field experiment performed on the coastal site of nuclear power plant in the east part of china during 1995 to 1996. The three-dimension joint frequency are obtained by hourly observation of wind and temperature on a 100m high lower; the frequency of the 'event day of land and sea breeze' are given by observation of surface wind and land and sea breezes; the diffusion parameters are got from measurements of turbulent and wind tunnel simulation test. A new model calculating the annual mean atmospheric dispersion factor for coastal site of nuclear power plant is developed and established. This model considers not only the effect from mixing release and mixed layer but also the effect from the internal boundary layer and variation of diffusion parameters due to the distance from coast. The comparison between results obtained by the new model and current model shows that the ratio of annual mean atmospheric dispersion factor gained by the new model and the current one is about 2.0.

关键词： Coastal zones Diffusion Dispersions earth atmosphere Temperature Wind

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Interdecadal change in Western Pacific Subtropical High and climatic effects

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Journal of Geographical sciences 2002年第2期12卷 79-86页

作者： HE Xue-zhao1, GONG Dao-yi1,2.(1. Laboratory of environmental Change and Natural Disaster Research, Institute of Resources Science, Beijing Normal university, Beijing 100875,{2. 2. School of earth and environmental sciences, Seoul National university Laboratory of environmental Change and Natural Disaster Research Institute of Resources Science 北京 100875 School of earth and environmental {2. Seoul National University 韩国 Seoul 151-742

Western North Pacific Subtropical High is a very important atmospheric circulation system influencing the summer climate over eastern china. Its interdecadal change is analyzed in this study. There is a significant decadal shift in about 1979/1980. Since 1980, the Western North Pacific Subtropical High has enlarged, intensified, and shifted southwestward. This change gives rise to an anti-cyclonic circulation anomaly over the region from the South china Sea to western Pacific and thus causes wet anomalies over the Yangtze River valley. During the summers of 1980-1999, the precipitation is 63.9 mm above normal, while during 1958-1979 it is 2..3.mm below normal. The difference is significant at the 99% confidence level as a t-test shown. The southwestward expanding of the Western North Pacific Subtropical High also leads to a significant warming in southern china, during 1980-1999 the summer mean temperature is 0.3.篊 warmer than that of the period 1958-1979. The strong warming is primarily due to the clearer skies associated with the stronger downward air motion as the Western North Pacific Subtropical High expanding to the west and controlling southern china. It is also found that the relative percentage of tropical cyclones in the regions south of 2.篘 is decreasing since the 1980s, but in the regions north of 2.篘 that is increasing at the same time. The Western North Pacific Subtropical High responds significantly to sea surface temperature of the tropical eastern Pacific with a lag of one-two seasons and simultaneously to sea surface temperature of the tropical Indian Ocean. The changes in the sea surface temperatures are mainly responsible for the interdecadal variability of the Western North Pacific Subtropical High.

关键词： Western Pacific Subtropical High interdecadal change climate change

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Titanium Aluminides: Science, Technology, Applications and Synthesis by Mechanical Alloying

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Journal of Materials Science & Technology 1994年第4期10卷 251-262页

作者： F.H.Froes (Institute for Materials and Advanced processes (IMAP), college of Mines and {2. Resources, {3. of Idaho, Moscow, Idaho 83.43.4195, USA) Univ of Idaho Idaho United States

The production. characteristics. and commercialization of monolithic and composite titanium aluminides are summanzed with emphasis on use in the demanding aerospace industry. The attractive elevated temperature properties combined with alow density make these materials of great interest, but inherently low 'forgiveness', and environmental concerns, must be overcome before widespread use will occur One synthesis method for the production of monolithic titanium aluminides-mechanical alloying- will be discussed in detail

关键词： ASM Applications and Synthesis by Mechanical Alloying Science Technology TMS

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Study on the simulation of transparency of Lake Taihu under different hydrodynamic conditions

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Science china earth {2. 2006年第z1期49卷 162-175页

作者： PANG Yong, LI Yiping & LUO Liancong college of environmental Science and Engineering, Hohai {2., Nanjing 2.0098, china Nanjing Institute of Geography & Limnology, Chinese Academy of sciences, Nanjing 2.0098, china Hohai Univ Coll Environm Sci & Engn Nanjing 210098 Peoples R China Chinese Acad Sci Nanjing Inst Geog & Limnol Nanjing 210098 Peoples R China

It was indicated in this study that there were negative relations between the concentrations of suspended solid (SS) and transparency according to the analysis of measured data of Lake Taihu. Their relations in pervious studies were reviewed, which showed that the changes of transparency in Lake Taihu could be reflected by simulating suspended solid concentration (SSC). Measured data showed that the changes of SSC with wind speed were similar at different water *** increased with the increasing of wind speed. Both wave and lake current of Lake Taihu had positive relations with SSC. However, wave was the main factor affecting sediment suspension, while flow took the second place. In this study, a numerical model coupling lake current, wave and SSC of Lake Taihu was developed. In the SS model, the combined effects of wave and current were *** amounts of suspended and deposited sediments near the lake bed surface layer were treated separately. The stochastic characteristics of turbulent flow pulsation near lake beds were also considered, and the start-up conditions of sediment suspension were introduced to the model. The model elucidated the mutual exchange processes between sediment particles in SS and active sediments within and on the bed surface layer. Simulated results showed that lake current had relatively significant effects on the SSC at littoral areas of Lake Taihu, while SSC at the central area of the lake was mainly influenced by wave. The changes of transparency with SSC were simulated for Lake Taihu using this model. Calculated results were validated by measured data with good fitness, which indicated that the model is basically suitable for the simulation and prediction of transparency of Lake Taihu.

关键词： transparency suspended solid hydrodynamlc sediment suspension model.

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environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,china

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2.1 State Key Laboratory of Vegetation and environmental Change,Institute of Botany,Chinese Academy of sciences,Beijing 100093.{2. 2.School of Geographic and Oceanographic sciences,Nanjing university,Nanjing 2.0093.china 1. State Key Laboratory of Vegetation and environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. School of Geographic and Oceanographic sciences Nanjing University Nanjing 210093 China

environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 3. kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

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