透射射线的非线性效应     

夏冬明  王修田  蒋卫焱 《中国海洋大学学报(自然科学版)》2006,36(5):705-708

根据Snell定律提出了透射射线的非线性效应的概念,从理论上证明了当地震射线的轨迹在1个界面上为1条直线时在另1个界面上可为1条曲线;并进一步通过射线追踪实验证明:当地下介质为非水平层状介质时,即使对应于地面同一条直线段上的接收点,来自地下同一个界面上的反射点的轨迹仍可为一条曲线。  相似文献   

An Application of Direct Ritz Method for Random Seismic Responses of Jacket Platforms     

韩晓双马骏  赵德有周波 《中国海洋工程》2006,20(4):673-679

1 .IntroductionNowadays tremendous efforts have been devotedtothe analysis of randomseismic responses .Forexample ,American PetroleumInstitute (API) has declared that the analysis of randomseismic re-sponsesis a useful tool for safety inspection. Owing to the complexity of platformand randomness ofload,it is difficult to carry out the randomresponse analysis of a jacket platform. The conventionalrandomvibration methods ,such as square root of the sumof squares (SRSS) and complete quadratic…  相似文献   

桩式离岸堤保滩促淤工程消浪效果试验研究   总被引：9，自引：0，他引：9  

龚崇准  陈美发等 《海洋工程》2001,19(4):72-77

在上海奉贤南北港保滩促淤工程中，采用了一种新型结构型式－桩式离岸堤，并通过物理模式试验进行了桩式离岸堤消浪效果研究。针对离岸堤通常建于近岸水区破波带的特点，重点研究水深，堤高以及堤身结构对波浪衰减的影响，同时对桩式离岸堤堤后水域的波浪底流速 分析探讨。研究结果表明，桩式离岸堤不仅具有良好的消浪效果。而且可在较大范围内改变波态，即由引起水体剧烈紊动的破波转变为浅水推进波，从而有效地改善海滩上的动力条件，促进海滩免受侵蚀，是一种具有广泛应用前景和新型保滩促淤结构。  相似文献   

河口变形效应与涌潮的形成     

杜勇 《中国海洋大学学报(自然科学版)》1989,(3)

作者采用非线性潮波方程,假定河口的宽度B(x)和深度h(x)是任意可微函数,导出了涌潮发生的条件,并讨论了各种变形情况下涌潮的形成。得出结论是,在涌潮形成过程中起决定作用的是浅水非线性效应,而河口变形效应则是起促进作用的。  相似文献   

Types and characters of sub-bottom acoustic reflection in eastern part of Bohai Sea     

Wang Kuiyang  Liu Zhenxi  Xia Dongxing 《海洋学报(英文版)》1997,16(2):225-237

Ｈｉｇｈ－ｒｅｓｏｌｕｔｉｏｎｓｕｂ－ｂｏｔｔｏｍｐｒｏｆｉｌｅｒｈａｓｒｅｖｅｄｅｄｓｅｄｉｍｅｎｔａｌｓｔｒａｔａａｎｄｅｎｔｉｒｏｎｍｅｎｔｓｉｎｔｈｅｅｕｔｔｍｐ．ｏｆｔｈｅｌ３ｏｈａｉＳｅａｓｉｎｃｅｔｈｅｌｔａｔｅＰｌｅｉｓｔｏｃｅｎｅ．Ａｔｃｃｏｒｄｉｎｇｔｏｔｈｅｃｈａｒａｃｔｅｒｓｏｆａｃａｕｓｅｉｃｒｅｆｌｅｃｔｉｏｎａｎｄｓｅｉｓｍｉｃｔｓｔｒａｔｔｌｇｍｐｈｉｃｐｒｉｎｃｉ－ｐｌｅ，ｓｏｍｅｃｌｔ．ｉｆｉｃａｔｉｏｎｏｆｔｙｐｉｃａｌａｃｏｕｓｔｉｃｒｅｆｌｅｃｔｉｏｎｉｓｎｚａｄｅｏｕｔｔｎｄｗｉＵｂｅｆａｖｏｕｒａｂｌｅｆｏｒｉｎｔｅｒｐｒｅｔａｔｉｏｎａｎｄｒｅｃｏｇｎｂａｔｉｏｎｏｆａｏｏｕｓｔｉｃｐｒｏｆｉｌｅｓｉｎｔｈｉｓａｒｅａ  相似文献   

鲁南近浅海沉积物样品的因子分析及其地质意义     

陈敬冉  林振宏 《中国海洋大学学报(自然科学版)》1988,(3)

本文提出河流携带入海的沉积物或沿岸剥蚀物中矿物的分布及再组合是受多种因素控制的。为了确定控制鲁南两城河至白马河沉积物样品中矿物分布及再组合的主要因素,作者对该区109个沉积物样品的重矿物资料进行了Q型和R型因子分析。研究指出,在诸多的河流中,白马河和两城河是控制该区沉积物分布的最上要的河流;矿物的化学稳定性是决定该区矿物再组合的主要因素。  相似文献   

Reflection of surface waves by submerged cylinders     

John Grue  Enok Palm 《Applied Ocean Research》1984,6(1):54-60

Reflection from submerged cylinders are studied by means of integral equations. By expressing the solution as a distribution of vortices, the integral equations become non-singular for closed contours. It is shown that the method gives a short and easy proof for the classical result that no reflection occurs for the circular cylinder. The reflection power for the elliptic contour and the flat plate are studied when the bodies are situated deeply below the surface.  相似文献   

塘沽海区海底地形的SAR影像仿真与反演研究   总被引：1，自引：0，他引：1  

夏长水  袁业立 《海洋科学进展》2003,21(4):437-445

利用袁业立、金梅兵(1997)提出的海底地形SAR影像仿真与反演模型，对渤海塘沽海区的一张Radarsat SAR影像进行了仿真和水深反演研究。研究结果表明：仿真影像与真实SAR影像基本吻合，反演水深与实际水深也有较好的一致性；进一步证实了袁业立(1997)SAR成像机理的正确性和在中国近海利用SAR影像进行浅海水深探测的可行性。  相似文献   

Hydrocarbon Potential of Pre-cenozoic Strata in the North Yellow Sea Basin     

蔡峰戴春山  陈建文李刚 孙萍 《海洋通报(英文版)》2005,7(1):21-36

The North Yellow Sea Basin ( NYSB ), which was developed on the basement of North China (Huabei) continental block, is a typical continental Mesozoic Cenozoic sedimentary basin in the sea area. Its Mesozoic basin is a residual basin, below which there is probably a larger Paleozoic sedimentary basin. The North Yellow Sea Basin comprises four sags and three uplifts. Of them, the eastern sag is a Mesozoic Cenozoic sedimentary sag in NYSB and has the biggest sediment thickness; the current Korean drilling wells are concentrated in the eastern sag. This sag is comparatively rich in oil and gas resources and thus has a relatively good petroleum prospect in the sea. The central sag has also accommodated thick Mesozoic-Cenozoic sediments. The latest research results show that there are three series of hydrocarbon source rocks in the North Yellow Sea Basin, namely, black shales of the Paleogene, Jurassic and Cretaceous. The principal hydrocarbon source rocks in NYSB are the Mesozoic black shale. According to the drilling data of Korea, the black shales of the Paleogene, Jurassic and Cretaceous have all come up to the standards of good and mature source rocks. The NYSB owns an intact system of oil generation, reservoir and capping rocks that can help hydrocarbon to form in the basin and thus it has the great potential of oil and gas. The vertical distribution of the hydrocarbon resources is mainly considered to be in the Cretaceous and then in the Jurassic.  相似文献   

Examination of empirical formulas for wave shoaling and breaking on steep slopes   总被引：1，自引：0，他引：1  

Ching-Piao Tsai  Hong-Bin Chen  Hwung-Hweng Hwung  Ming-Jen Huang 《Ocean Engineering》2005,32(3-4):469-483

Estimation of the wave height transformation of shoaling and breaking is essential for the nearshore hydrodynamics and the design of coastal structures. Many empirical formulas have been well recognized to the wave height transformation, but most of them were only applicable for gentle slopes. This paper reports the experimental results of wave shoaling and breaking over the steep slopes to examine the applicability of the previous empirical formulas. Two steep bottom slopes of 1/3 and 1/5, and one gentle slope of 1/10 were conducted in the present experiments. Experimental results show that the shoaling distance of steep slopes become short and the surface waves may be partially reflected from the steep bottom, thus the estimation of wave shoaling using the well-known previous formula did not conform completely to the experimental results. The previous empirical formulas for the wave breaking criteria were also examined, and the modified equations to the steep beaches were proposed in this work. A numerical model was finally adopted to calculate the wave height transformation in the surf zone by introducing the modified breaking index.  相似文献