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1.
Geochemical patterns of shelf sediments of China Seas are discussed in the following order: 1) the grain-size control of elements, 2) zonal distribution of elements along the coast, 3) estuarine enrichment of elements, 4) correlation of elements, 5) philo-detrital property of elements, 6) philo-continental property of elements, 7) rapid accumulation rate of elements. Statistics show that the abundance of indicator elements in shelf sediments is relatively close to that in terrestrial rocks and continental crust, and the abundance distribution pattern of elements in shelf sediments is similar to that in continental crust.  相似文献   

2.
The paper presents a numerical two-dimensional model (with a realistic sea basin and wind fields as exter nal forcing) to simulate the basic features of the wintertime circulation in the Bohai and Huanghai (Yellow) Seas (BHS) and to show how the circulation can be driven by wind. The main results can be summarized as follows (1) The basic features of the BHS wintertime circulation can be depicted by the wind-driven barotropi'c motion. (2) The traditionally named Huanghai Sea Warm Current (HSWC) is actually generated by the north wind field, at least in winter. (3) The southward coastal current off the Korean west coast plays a more significant role in the southern Huanghai Sea wintertime circulation than traditionally believed. (4) Though the coastal landform and bottom topography play important roles in the wintertime BHS circulation pattern, the wind is a primary forcing.  相似文献   

3.
Determination of the concentrations of. 15 rare earth elements (REE) in China continental shelf sediments by X- ray fluorescent spectral analysis of selected representative sediment samples showed that REE concentration in the sediments is 156 ppm, similar to that in China loess and Fujian granite, but different from that in Pacific sediments. The shelf REE have the characteristic distribution pattern of typical continental crust REE and evidently philo-continental property. The above findings suggest that weathered materials transported from the China continent are the main source of the REE in China continental shelf sediments.Experiments show that REE exist mainly in the crystal lattices of clay minerals ( <2u) as isomorphs and that REE have close relation with most elements (Al, Ti, K, Rb, Fe, etc.) related with clay minerals, but have negative correlation with the biophile elements Ca and Sr.  相似文献   

4.
THEPROCESSANDSTRATEGYOFURBANIZATIONDEVELOPMENTINNORTHWESTCHINAZhangZhiliang(张志良)(PipulationResearchInstituteofLanzhouUniversi...  相似文献   

5.
In the later stage of Late Pleistocene, global climate entered into the climax period of Wurm when temperature decreased remarkably and glaciers developed. Information from the East China Sea also confirm that the sea level fell by at least 130 m at that time (Emery, 1968). The Bohai Sea and Yellow Sea at the climax period were totally exposed, while the East China Sea and South China Sea shelf regions were exposed partly. The exposed shelf area exceeded 1 million km2 and became a salty desert where land plants could not survive. Such were the conditions which led to the desertization of the shelf region.Eolation was the major exogenetic force not only on land but also on the shelf region in the ice age. At the climax period of Wiirm, the northern part of China developed thick layers of loess deposits. The shelf region at that time had similar climatic conditions and sediments. Because the shelf region was not protected by vegetation in the ice age, intensive wind storms remoulded the primarily deposite  相似文献   

6.
In order to understand the properties of the winter circulation in the northern China Sea, a two-dimensional numerical model has been established and calculated for an ideal sea basin.In the model we employed a quadratic conservative scheme for a complete set of dynamic and thermodynamic equations. The systematic analysis of stability produced a series of mathematically and physically restrictive conditions which are more general than those derived by Irvine, and Chen.Using this model we made calculations on a series of interesting phenomena, such as the Yellow Sea Warm Current, two gyres in the Yellow Sea, etc. as well as their developing processes. The simulation can also explain the generation mechanism of the phenomena.  相似文献   

7.
Regarding climate change in China, ordinary people, even meteorologists, would think the cold waves from Siberia dominate winter temperature in southeast China. As oceanographers, however, we must know the role of ocean circulation in climate change. This text briefly discusses how important is the role of the Western Pacific Ocean circulation in climate change in southeast China on the basis of CTD data gathered by the R/V Science 1 in the western Pacific in September and October, 1986 and 1987 respectively , and statistical air temperature data in southeast China.  相似文献   

8.
A NOTE ON CIRCULATION OF THE EAST CHINA SEA   总被引:2,自引:2,他引:0  
The East China Sea lies over a wide continental shelf off the coast of China. Just like its neighbouring areas Bohai Sea and Huanghai Sea, the major part of the East China Sea is of a shallow water area, its mean depth being about 370 m. On the average, the annual discharge of fresh water into Bohai Sea, Huanghai Sea and the East China Sea is" about 1.5×10~(12)m~3, and among these, about 80% is discharged into the East China Sea, the Changjiang River alone accounts for about 9×10~(11)m~3/year. Mixed with this large amount of fresh water the coastal water is of low salinity in this area. This Coastal Water System flows, generally, from north to south. Off the outer margin of the continental shelf, a powerful flow characterized by high temperature and high salinity and known as the Kuro-  相似文献   

9.
North China, whose total area is 420,000 km2, covers 2 provinces and 2 cities (Shanxi and Hebei provinces, Beijing and Tianjin) and the territories of Henan and Shandong provinces to the north of the Huanghe (Yellow) River, and part of the Inner Mongolia Autonomous Region and Liaoning Province. Most of this region, which is situated in the semi-humid, semi-arid continental climate temperate zone, gets an annual precipitation of 500-600 mm, whereas, the perennial average amount of total water resource is 50.99 billion m3, including 33.82 billion m3 of surface water, 32.94 billion m3 of ground water and 15.77 billion m3 of their duplication. Due to the intensive exploitation of water resource caused by the deficiency of water resource in North China, key elements of water balance was changed, runoff volume reduced, evaporation increased, vertical movement of moisture strengthened, water circulation pattern transformed from open system into regionally closed system; meanwhile, due to the incompetent water  相似文献   

10.
This is a brief introduction of the Kuroshio in the East China Sea (ECS). The main results of the study for this part of the Kuroshio system in recent years are reviewed and presented with emphases placed on the major features of the current structure, annual and inter-annual variations of the velocity and volume transport of the Kuroshio in ECS, and the relation between the variation of the Kuroshio in ECS and that of the Kuroshio south of Japan. And finally, an indirect relation between the variation of the Kuroshio in ECS and that of the North Equatorial Current system is suggested. It is shown that the fluctuation of the Kuroshio in ECS is also correlated with that of the North Equatorial Current and North Equatorial Counter-current. Ties of the above relation are the wind stress curl field over the tropical and subtropical belts.  相似文献   

11.
Regarding the current pattern in winter in the near-sea region of Zhejiang, Fujian and Guangdong (including the western and central parts of the Taiwan Strait), oceanographers both at home and abroad had considered unanimously that under the intense influence of the northerly monsoon, the current (not only at the surface but also in the deep and near-bottom layers) flows southwestward with the wind. It was not until the end of the fifties that scientists began to question such a traditional concept.In this paper, based on the results of more than 20 years' studies on the current patterns of the East China and South China Seas, all kinds of current data available are reanalysed comprehensively. These data include: 1) current measurements at day-night anchored stations, and with mooring buoys, collected mostly from 1959 to 1982 by many Chinese oceanographic and fisheries organizations; 2) current vectors derived from the ship-drift of Japanese naval vessels in the period from 1910 to 1921; and 3) geostrop  相似文献   

12.
ImODUcrIONTheIndo-PadricregionbeweenMindanao,NewGuinea,andtheIndonesianArchipelagoistheonlydeeppassagefromthePadricOceantotheIndiandrincyig.l),Fig.lMapoftheIndoThdficopon(Internalframeisthemodeldomain)andobendupper1aperimtSthereinsmrandhasareivedconsiderableattentionhauseofitSlocationbetweretheIn.TheIndonesianThappearstobepotentiallyboortantintheevoluhonsofthewesternboundaryatandthewarmpoolinthewesternPadric,andplaysacrudelroleinthehcatandsaltbalanceoftheworkl'soasnoprdon,l986).Nume…  相似文献   

13.
A global atmospheric general circulation model (L9R15 AGCMs) forced by COADS SST was integrated from 1945 to 1993. Interannual and interdecadal variability of the simulated surface wind over the tropical Pacific was analyzed and shown to agree vey well with observation. Simulation of surface wind over the central-western equatorial Pacific was more successful than that over the eastern Pacific. Zonal propagating feature of interannual variability of the tropical Pacific wind anomalies and its decadal difference were also simulated successfully. The close agreement between simulation and observation on the existence of obvious interdecadal variability of tropical Pacific surface wind attested to the high simulation capability of AGCM.  相似文献   

14.
A simple and practical method for separating low-frequency internal waves from low-frequency barotropic waves was employed to analyze the observation data. Analysis of some data gathered in the northestern China Seas revealed strong semidiurnal internal tides and near-inertial internal waves at the stations in the East China Sea and near-inertial waves but no semidiurnal internal tides at the station in the centre of the Yellow Sea. The geographic properties of low-frequency internal waves in the region are discussed primarily on the basis of the mechanism of internal tide generation on the continental shelfbreak,and the mechanisms of local generation and global generation.  相似文献   

15.
Surveys since 1959 showed that the dynamic basis of the East China Sea sectional circulation is the nearshore seawater horizontal divergence caused by wind on the surface compensated by Kuroshio subsurface water convergence caused by meridional current in the lower layer.Fish always tend to migrate along certain routes or stay in certain areas favorable for development of eggs, survival of larvae and living of adults. The movement of water masses supplies a very important driving force for marine animals migrating long distance.The lower part of the sectional circulation formed by the subsurface water of Kuroshio is not suitable for the aggregation offish because of its lack of oxygen, and has therefore a driving influence on demersal fishes.This study of the sectional circulation influence on the distributions of some commercially important species in the East China Sea reveals a close relationship between the circulation and the movement of fish schools.The principal factors influencing zonal vertical  相似文献   

16.
The article, in a comprehensive view, explores the strategic vantages, strategic urgency, strategic goals, strategic planning as well as strategic steps.  相似文献   

17.
Resource-type industries are significance in national economy in the initial stage of industrialization and urbanization in developing countries including China. China is abundant in energy resources, but their distribution is uneven. The prospect of iron and steel industry from the supply of iron ore and coal as well as nonferous metallurgical industry, and chemical industry, is discussed. Processing of agricultural product is an important component of resource-type industries, and the base of light industry. The current status of light industry and different potentials in China's provinces are analysed. The author classifies all provinces into five types according to the spatial combination of minerals in China, and argues that four indicators have to be taken into account with regard to the appraisal of geographical position.  相似文献   

18.
According to the theory of sustainable development, the current situation and existent problemsoftheexploita-tion of water resources were analyzed in this paper. The results show that the contradiction between supply and demandof water resources is continually aggravating, water pollution is increasingly serious, water environment is worse, theover-extraction area of the underground water is expanding and water crisis stands out gradually, so it is imperative underthe situation to actualize the sustainable exploitation strategies of water resources. It is necessary for sustainable utilizingwater resources to introduce the model of sustainable utilization of water resources the model of wealth transferring be-tween the generations of water resources, establish water-saving society system and water market, form technology sys-tems, management systems and evaluation systems for many sorts of water resources, improve the utilization ratio of waterresources, transform waste water into resources and maintain and restore the water space of water environment.  相似文献   

19.
Collinear analysis technique is widely used for determining sea surface variability with Geosat altimeterdata from its Exact Repeat Mission(ERM).But most of the researches have been only on global scaleor in oceans deeper than 2000 m.In shallow shelf waters this method is hampered by the inaccuracy ofocean tide data supplied with Geosat Geophysical Data Records(GDRs).This work uses a modified collinearanalysis technique characterized by simultaneous separation of mean sea level and ocean tide with theleast squares method,to compute sea surface variability in the Northwest Pacific Ocean and eastern ChinaSeas.The mean sea level map obtained contains not ouly bathymetric but also dynamic features such asamphidromes,indicating considerable improvement over previous works.Our sea surface variability mapsshow clearly the main current system,the well-known Zhejiang coastal upwelling,and a northern East Chi-na Sea meso-scale eddy in good agreement with satellite sea surface temperature(SST)observation and his-to  相似文献   

20.
INTRODUCTIONThehorizontalcurrentintheseaoroceanisamajorfactoraffectingsedimenterosion ,trans port,deposition ,etc.Therefore,mostworkdonewasontheeffectofhorizontalcurrent.Fewo ceanographershavetakennoteoftheinfluenceofverticalcirculationonthesuspendedmatte…  相似文献   

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