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Chinese Journal of Oceanology and Limnology 1989年第1期7卷 89-92页

作者： D.D.Badyukov E.L.Demidenko P.A.Kaplin dept. of geography State Univ. Moscow USSRDept. of Geography State Univ. Moscow USSRDept. of Geography State Univ. Moscow USSR

The-Seychelles Bank and Madagascar Shelf in the western Indian Ocean were explored geologically during a cruise of the R/V "professor Shtokman" in 1986. Using the data of relief, sediment characteristics and their sequences of strata, paleogeographic maps (18,000 a B.P.) of these areas were produced. These maps show that the Bank and the Shelf are carbonate platforms with complicated topography. The data indicate an important role of sea level oscillation in relief development of this area.

关键词： carbonate strata lacustrine relief professor Indian cruise northwest sedimentation intrusive

STRATIGRAPHIC AND GEOCHRONOLOGIC ANALYSES OF THE QUATERNARY DEPOSITS IN THE THREE-LAKE REGION OF QAIDAM BASIN

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Science China Chemistry 1991年第8期34卷 987-1006页

作者：刘泽纯汪永进杨藩周翥虹 dept. of geography Nanjing Normal University Institute of Oil Exploration Qinghai Oil Bureau

The Qaidam Basin is a larger sedimentary basin in western China where the thickness of the Quaternary deposits is in the range of 2000-3000 m at its subsiding center. This paper first dates palaeomagnetically the cores obtained from the five continuously sampled intervals and those from a typical profile, determineds the age of the index fossil zones, and calculates the deposition rates for the varve deposits based on the sedimentological analysis. As a result, we can calculate the ages of the various characteristic beds (including fossil zones, seismic reflection beds, and marker layers of electrical properties) for any given borehole-section when it was divided into facies, and check the validity of the chronology. According to all those studies, the stratigraphic and geochronologic analysis program of the Quaternary deposits in the Qaidam Basin has permitted a detailed discussion to be made in this paper.

关键词： mudstone facies sedimentary Quaternary stratigraphic fossil borehole shallow sandstone environments

Relationships Between Tidal Prism and Throat Area of Tidal Inlets Along Yellow Sea and Bohai Sea Coasts

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China Ocean Engineering 1996年第2期11卷 229-238页

作者： Zhang Renshun and Wang Yaping Professor, dept. of geography, Nanjing Normal University, Nanjing 210024 Lecturer, Nanjing Normal University, Nanjing 210024 dept. of geography Nanjing Normal University Nanjing 210024 Nanjing Normal University Nanjing 210024

The relationship between P (spring tidal prism) and A (throat area below mean sea level) is statistically analysed in terms of 29 tidal inlets or bays along the Huanghai Sea (Yellow Sea) and Bohai Sea coasts. For 15 of these tidal inlets, the best regression equation is A(km2) = 0.845 />(km3)1.20. The analysis shows that C and n are little different from those in the P-A relationship for the inlets of the South China Sea and East China Sea coasts. It is noted that the relationship between P and A is unstable because of the difference in sediment abundance. The study shows that a united P-A relationship can be obtained for the tidal inlets of lagoon type and bay-drowned-valley type, not containing some half-circle shape bays which confront deep water. These half-circle bays do not belong to tidal inlets because they do not have enough sediment abundance and are fairly open.

关键词： tidal inlet P-A relationship Huanghai Sea (Yellow Sea) Bohai Sea

Issues of the Holocene transgression on the southern plain of the Changjiang Delta

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Acta Oceanologica Sinica 1988年第4期7卷 578-590页

作者： Yan Qinshang and Hong Xueqing Department of geography, East China Normal University, Shanghai, China dept. of geography East China Normal Univ. Shanghai China. China

The paper deals with the question of Holocene transgression on the southern plain of the Changjiang *** the beginning of the transgression, the paleovalleys of the Changjiang and Qiantang Rivers were covered by sea water at *** shoreline of 8000-7500 yr BP coincided with the -7m isobath of paleotopography. Sea level had already been the present level about 7000-6500 years ago, and the Holocene transgression reached its maximum extent. During the period, the Changjiang and Qiantang Rivers and the Dongtiaoxi valley were turned into estuaries; the eastern area of Shanghai became a shallow sea; some of the bays and lagoons were distributed on the Hang-Jia-Hu and Tao-Ge Plain; the hilly region around the Taihu Lake was coastal marsh and freshwater swamp. Gangshen on the west of Shanghai was formed 7000-4000 yr BP, and during the last 4000 years, the eastern coastal plain of Shanghai advanced quickly toward the sea, and partial clear land of the western Taihu Lake was enclosed and charged into a fre

关键词： Ho Issues of the Holocene transgression on the southern plain of the Changjiang Delta

Community-based scenario modelling and disaster risk assessment of urban rainstorm waterlogging

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Journal of Geographical Sciences 2011年第2期21卷 274-284页

作者： YIN Zhan'e YIN Jie XU Shiyuan WEN Jiahong geography dept. of Shanghai Normal University Shanghai 200234 China geography dept. of East China Normal University Shanghai 200062 China

Scenario modelling and the risk assessment of natural disasters is one of the hotspots in disaster research. However, up until now, urban natural disaster risk assessments lack common procedures and programmes. This paper selects rainstorm waterlogging as a disaster to research, which is one of the most frequently occurring hazards for most cities in China. As an example, we used a small-scale integrated methodology to assess risks relating to rainstorm waterlogging hazards in the Jing＇an District of Shanghai. Based on the basic concept of disaster risk, this paper applies scenario modelling to express the risk of small-scale urban rainstorm waterlogging disasters in different return periods. Through this analysis of vulnerability and exposure, we simulate different disaster scenarios and propose a comprehensive analysis method and procedure for small-scale urban storm waterlogging disaster risk assessments. A grid-based Geographical Information System （GIS） approach, including an urban terrain model, an urban rainfall model and an urban drainage model, was applied to simulate inundation area and dept.. Stage-damage curves for residential buildings and contents were then generated by the loss data of waterlogging from field surveys, which were further applied to analyse vulnerability, exposure and loss assessment. Finally, the exceedance probability curve for disaster damage was constructed using the damage of each simulated event and the respective exceedance probabilities. A framework was also developed for coupling the waterlogging risk with the risk planning and management through the exceedance probability curve and annual average waterlogging loss. This is a new exploration for small-scale urban natural disaster scenario simulation and risk assessment.

关键词： scenario modelling small-scale rainstorm waterlogging disaster risk assessment Shanghai

Water resources optimization and eco-environmental protection in Qaidam Basin

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Journal of Geographical Sciences 2001年第2期11卷 231-238页

作者： FANG Chuang-lin~1, BAO Chao~2 (1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China 2. dept. of geography, Peking University, Beijing 100871, China) Institute of Geographic Sciences and Natural Resources Research CAS dept. of geography Peking University

In order to realize sustainable development of the arid area of Northwest China, rational water resources exploitation and optimization are primary prerequisites. Based on the essential principle of sustainable development, this paper puts forward a general idea on water resources optimization and eco-environmental protection in Qaidam Basin, and identifies the competitive multiple targets of water resources optimization. By some qualitative methods such as Input-output Model & AHP Model and some quantitative methods such as System Dynamics Model & Produce Function Model, some standard plans of water resources optimization come into being. According to the Multiple Targets Decision by the Closest Value Model, the best plan of water resources optimization, eco-environmental protection and sustainable development in Qaidam Basin is finally decided.

关键词： water resources optimization Multiple Targets Decision by the Closest Value Model eco-environmental protection Qaidam Basin

Spatial Dynamics of Cropland and Cropping Pattern Change Analysis Using Landsat TM and IRS P6 LISS III Satellite Images with GIS

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Geo-Spatial Information Science 2009年第2期12卷 123-134页

作者： Md.Rejaur Rahman S.K.Saha dept. of geography and Environmental Studies University of Rajshahi

The study of the spatial patterns and temporal changes of cropland is important to understand the underlying factors and the functional effects of the agricultural landscape. On the other hand, crop dynamics mapping is essential to know the overall agro-spatial diversity of the area. Therefore, this paper addressed a spatio-temporal analysis of cropland and cropping pattern change in the Bogra district of Bangladesh over the last 16 years （between 1988/89 and 2004/05）. In this paper, crop mapping from multi-temporal and multi-sensor satellite images was described. Landsat TM and IRS P6 LlSS Ⅲ satellite images were used with GIS for spatial dynamics of cropland and cropping pattern change analysis. First, seasonal cropland maps were derived from object-based classification of satellite images, then two-date classified image differencing with GIS overlay technique and decision rules were applied. Cropping pattern change was analyzed in a spatial and quantitative way for the 16 years and for this, Integrated Land and Water Information System （ILWIS） and Land Change Modular （LCM） of IDRISl Andes were used. The results showed that in the area, mono crop cultivation was found in summer, but in winter, areas under different crop cultivation had changed dramatically. Change analysis showed that the changes mainly occurred in the north northwest and southwest of the areas, and during the time the highest change area was found under the rice-potato pattern.

关键词： cropland dynamics gain and loss of cropland spatial trend cropping pattern change Landsat TM and IRS P6 LISS Ⅲ GIS

Grain-size cycles in Salawusu River valley since 150 ka BP

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Journal of Geographical Sciences 2001年第4期11卷 81-92页

作者： ZHANG Yu-hong LI Bao-sheng JIN He-ling David Dian ZHANG YAN Mun-cun ZHU Yi-zhi YAO Chun-xia dept. of geography South China Normal University State Key Lab of Loess and Quaternary Geology Institute of Earth Environment CAS Cold and Arid Regions Environmental and Engineering Research Institute CAS dept. of geography and Geology Hong Kong University dept. of Hydraulic Engineering Tsinghua University State Key Lab of Loess and Quaternary Geology Institute of Earth Environment CAS dept. of geography South China Normal University

The palaeo-mobile dune sands and fluvio-lacustrine facies with palaeosols in Milanggouwan stratigraphic section of the Salawusu River valley situated at the southeast of the Mu Us Desert experienced abundant remarkable alternative changes of coarse and fine rhythms in grain-size since 150 ka BP, and the grain-size parameters Mz,σ, Sk, Kg and SC/D also respond to the situation of multi-fluctuational alternations between peak and valley values. Simultaneity the grain-size eigenvalues F5, F16, F25, F50, F75, F84 and F95 are respondingly manifested as greatly cadent jumpiness. Hereby, the Milanggouwan section can be divided into 27 grain-size coarse and fine sedimentary cycles, which can be regarded as a real and integreted record of climate-geological process of desert vicissitude resulted from the alternative evolvement of the ancient winter and summer monsoons of East Asia since 150 ka BP.

关键词： Salawusu River valley Milanggouwan section 150 ka BP grain-size palaeoclimate cycles

Microstructure and phase formation of mullite-Pr6O11 composite prepared by spark plasma sintering

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Journal of Rare Earths 2023年第2期41卷 283-289页

作者： Ehsan Ghasali Davoud Ghahremani Yasin Orooji Aida Faeghi-nia Asghar Kazem-zadeh Touradj Ebadzadeh College of geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China Ceramic dept. Materials and Energy Research CenterAlborzIran Department of Engineering Maybod BranchIslamic Azad UniversityMaybodIran

The present work investigates the effect of high praseodymium oxide(Pr6O11)content on the microstructure and phase formation of mullite(3Al_(2)O_(3)·2SiO_(2))precursor by means of the spark plasma sintering process.30 wt%Pr6O11was added to a mullite precursor consisting of aluminum nitrate nonahydrate and tetraethyl orthosilicate through a high energy mixer mill in ethanol *** spark plasma sintering was performed at a te mperature of 1200℃under 23 Pa vacuum co nditions by applying initial and final pressure of 10 and 30 MPa,*** analysis confirms the existence of mullite,alumina,Pr6O11,Pr2O3and quartz as the only crystalline *** images reveal an interesting deposition of hexagonal-shaped Al_(2)O_(3)particles on polished surfaces and complex oxide phases of the fiber network adhering to alumina particles in the form of tails seen on the fracture ***,the bending strength of 213±21 MPa,Vickers hardness of 9.3±0.1 MPa and fracture toughness of6.21±0.12 MPa·m1/2are obtained for the prepared composite.

关键词： Mullite Pr6O11 Composite Spark plasma sintering Rare earths

Variability of Carbonate Pedofeatures in a Loess-Paleosol Sequence and their Use for Paleoreconstructions

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Journal of Mountain Science 2009年第2期6卷 155-161页

作者： Kovda.I Sycheva S. Lebedeva M. Inozemtzev S. Institute of geography Staromonetny 29119017 Moscow Russia Institute of Soil Science Pyjevsky 7 119017 Moscow Russia dept. of Soil Science Moscow State University Leninskiye Gory119998 Moscow Russia

Carbonate pedofeatures were studied in details in a loess-paleosol pedocomplex near Kursk, in the central part of the European Plain. The soils studied included a modern Chernozem and five Pleistocene paleosols. Carbonate morphologies and distributions were described in the field. Various morphologies were sampled for further studies including micromorphology in thin sections and submicroscopic studies under a scanning electron microscope. The complex approach of investigation at macro-, micro-, and submicroscopic levels found that most of carbonate pedofeatures are secondary and multiphase. Many of them are related to cryogenic features. The general trend was of decreasing carbonate content in the older paleosols except for increased content in the 1St and 3rd paleosols. Most of carbonate morphologies are similar in the modern soil and paleosols, but pseudomycelium was found only in the modern Chernozem, while soft masses and impregnations are associated with the paleosols. Detailed study on carbonate attributes revealed their specific features in the modern soil and in paleosols. Veins have dissolution features under the modern environment and seem to reprecipitate in form of pseudomycelium. Coatings in paleosols at a dept. of the Ist paleosol include specific fine tubes. Powdery soft masses and impregnations in the paleosols are strongly related to cryogenic fissures and paleopermafrost level. Under SEM they consist of tiny crystals, much smaller than in regular soft masses. Several types of hard concretions were identified：rounded, irregular and platy. Small concretions in the modern Chernozem have similar morphology and similar 14C-age as the rounded concretions of the upper paleosols. They are expected to represent the same generation of concretions. Platy concretions fill the bottom part of the large fissures. The 14C-age of hard concretions varies from 3310±80 yrs. B.P in the Ist paleosol up to 20 400 yrs. B.P. in the 3^rd. As a result we found the reflectio

关键词： Loess-paleosol pedocomplex pedogeniccarbonates macr- and microforms