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1.
粉沙质海岸泥沙运动和淤积分析计算   总被引:15,自引:1,他引:14  
介绍了粉沙质海岸的泥沙运动特点,通过理论分析和水槽试验揭示出粉沙质海岸的泥沙淤积物中悬移质和推移质的比例,并提出粉沙质海岸淤积计算的方法。  相似文献   

2.
粉沙质海岸港口水域平面布局特点   总被引:6,自引:0,他引:6  
季则舟 《海洋工程》2006,24(4):81-85
从工程泥沙角度建议将泥沙中值粒径在0.03 mm≤d50≤0.10 mm的海岸定义为粉沙质海岸。粉沙质海岸泥沙具有易起动、沉降快、密实快的特性,由此决定了粉沙质海岸港口泥沙淤积的特点。与港口工程密切相关的近岸区域可分为淤涨型、侵蚀型和动态平衡型,同一地点,海岸地貌特征随外界影响因素的变化而变化。根据粉沙质海岸港口的泥沙淤积特点和实际经验,提出了在粉沙质海岸进行港口水域平面布局时应重点考虑的因素。根据已建港口情况,论述了适合粉沙质海岸的港口平面布局模式及应遵循的原则。  相似文献   

3.
分析了冰后期以来北黄海淤泥质海岸变迁及海岸地貌的形成和滩涂的自然分带。讨论了北黄海淤泥质海岸滩涂开发现状和存在的问题 ,提出了滩涂资源开发利用的模式。  相似文献   

4.
分析了冰后期以来北黄海淤泥质海岸变迁及海岸地貌的形成和滩涂的自然分带,讨论了北黄海淤泥质海岸滩涂开发现状和存在的问题,提出了滩涂资源开发利用的模式。  相似文献   

5.
石臼湾及其附近海岸地貌特征   总被引:3,自引:0,他引:3  
山东南部石臼湾及其附近沿岸地带,北起自马吉利——两城河口,南至绣针河口,全长近80公里,是一段较典型的基岩砂砾质海岸(图1)。它的北部为鲁东南基岩港湾式海岸,绣针河口区以南则为苏北粉砂淤泥质平原海岸。  相似文献   

6.
淤泥质、粉沙质及沙质海岸航道回淤统一计算方法   总被引:1,自引:0,他引:1  
根据20世纪80年代初提出的淤泥质海岸航道回淤计算方法的基础上,开展了拓展研究,使之统一适用于淤泥质海岸、粉沙质海岸及沙质海岸。主要研究内容有,在波浪和潮流综合作用下挟沙力含沙量研究中引入了特定的泥沙因子F1/F,从而挟沙力含沙量公式不仅适用于淤泥质泥沙,也适用于非淤泥质泥沙;在动力因素方面,除了一般寻常潮和波浪动力外,进一步考虑了风暴潮和破波的巨大掀沙能力造成航道骤淤的可能性。并结合连云港30万吨级主航道扩建及徐圩港区10万吨级航道的回淤问题(包括骤淤可能性问题),京唐港外航道和黄骅港外航道的骤淤问题,进行预测计算及校验计算,结果都是良好的。此外,对杭州湾强潮和涌潮情况下的挟沙力含沙量也进行了校验计算,结果也非常满意。  相似文献   

7.
淤泥质海岸潮间浅滩的形成和演变   总被引:3,自引:0,他引:3  
生产建设与国防建设的发展,迫切需要了解淤泥质海岸的某本情况及其演变规律。但是,由于观测工作的困难,资料积累有限,再加淤泥质海岸的形成和演变极为复杂,因而至今尚无完整的理论,以作实际工作的指导。所以加强对该类海岸的研究具有重要的实际意义和理论意义。  相似文献   

8.
悬移质挟沙力是粉沙质海岸航道骤淤预测的关键性参数,目前缺乏有效的研究成果。通过大尺度波浪水槽对缓坡下的粉沙质海岸骤淤期破波掀沙机理进行试验观测和研究,根据能量平衡原理,建立粉沙质海岸在崩破波作用下悬浮泥沙运动的能量平衡方程式。能量平衡方程式的要点在于波浪所提供的有效能量损耗中,除了传统的底摩擦损耗和悬浮泥沙所消耗的能量外,还应增加崩破波引起的能量损耗。在此基础上提出粉沙质海岸骤淤期悬移质挟沙力公式,并得到试验资料的初步验证。  相似文献   

9.
粉沙质海岸泥沙运动特性研究   总被引:2,自引:1,他引:1  
曹祖德  孔令双 《海洋学报》2011,33(5):152-162
文章对粉沙质海岸的泥沙运动特性进行了系统、全面的研究.从5个方面进行了论述:粉沙质海岸的界定、泥沙基本水力特性、泥沙运移型态、航道骤淤的统计特性和航道淤积计算.提出粉沙质海岸的界定应综合考虑泥沙平均中值粒径、黏土含量和泥沙粒径分选性三方面因素;泥沙基本水力特性是起动流速小、沉降速度大、沉积密实快,泥沙运动十分活跃;泥沙...  相似文献   

10.
淤泥质海岸近海风电塔基局部冲刷计算研究   总被引:1,自引:0,他引:1  
在淤泥质海岸修建近海风电塔基时,局部冲刷深度是设计的主要参数,目前相关研究成果较少。针对苏北淤泥质海岸拟建的响水近海风电塔基,选取自然条件相似的胜利埕岛油田海洋平台桩基局部冲刷现场观测资料,对常用的三种桩基局部冲刷公式进行了验证比较,推荐较为适宜的计算公式。在此基础上,提出了考虑波浪作用的改进方法,并对响水近海风电塔基的局部冲刷深度进行了计算。研究结果表明:1)经过对比分析,韩海骞公式较为适宜用来计算淤泥质海岸近海风电塔基的局部冲刷深度;2)对于淤泥质海岸近海风电塔基来说,波浪作用较为重要,不可忽略,可以采用波生流的方法加以考虑。  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

15.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

16.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

17.
The methodology and the first results of the computations of the volumes, masses, and growth rates of the sedimentary body of the buried Black Sea basin are presented. Their temporal evolution reflects the regional paleogeodynamics, in particular, the reorientation of the vector of the relative movement of the Arabian and Eurasian lithospheric plates and the related intensification of their collision in the late Miocene-Pliocene.  相似文献   

18.
The spatiotemporal variability of the hydrochemical composition of the riverine runoff in nearmouth areas is presented using the example of selected rivers of the Arctic Basin. The temporal dynamics of the riverine nutrient runoff are mainly determined by the seasonal and interseasonal variations in the drainage basins. The spatial variations in the chemical composition of riverine waters in the near-mouth areas are mainly caused by the dynamics of the water flow and the river bed relief and, to a lesser degree, by biochemical processes. It is shown that the variations in the nutrient composition of the waters in near-mouth areas are comparable in magnitude to those at the river-sea geochemical barriers.  相似文献   

19.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

20.
Izvestiya, Atmospheric and Oceanic Physics - Analysis of the temporal variations of the virtual heights of the sporadic E layer (h?ES) determined from ionograms with increased accuracy (1...  相似文献   

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