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91.
海浪数值模式研究回顾与进展   总被引:1,自引:1,他引:1  
闻斌  刘俊 《海洋预报》2006,23(4):76-81
本文简单介绍了海浪的生成、发展理论,以及海浪数值模式的分类;回顾总结了国内外在海浪数值模式研究方面取得的成果。  相似文献   
92.
海坛海峡二维潮流场数值模拟   总被引:2,自引:0,他引:2  
海坛海峡为南北狭长型海峡,海峡内潮波属于前进波.本文建立了平面二维浅水波数学方程,利用欧拉-拉格朗日差分方法得到数值解,模型采用随时间变化的动边界技术,成功地模拟了海坛海峡的前进波特征,并根据实测数据进行了验证.同时计算了同潮时线和等振幅线,不同时刻的潮流场和潮流平均流速分布.计算结果表明,北部湾口M2分潮高潮时间比南部湾口早约5~6min,等振幅线范围约为2.12~2.15m.海峡内流速分布呈南北强、中间弱的特点,最大流速1m/s左右.  相似文献   
93.
Mapping the seabed along the Norwegian coast is costly and time consuming. Hence, finding a modeling method to separate rocky seabed from other substrate types will provide digital maps that may be used to develop cost-effective sampling designs to predict species and habitat distribution. Our approach was to use geophysical data that were quantitative and objectively defined, generalized additive models (GAMs), and Akaike information criterion (AIC) to develop statistical models and select among them. We found that slope, terrain curvature, wave exposure, and depth predicted rocky seabed occurrence with a high degree of certainty.  相似文献   
94.
象山港水交换数值研究 Ⅱ.模型应用和水交换研究   总被引:21,自引:4,他引:21  
使用水平二维对流-扩散型水交换模式模拟研究了象山港的水交换,对不同区域的水交换控制机理作了初步探讨,象山港水交换状况与其控制机制的区域性变化很大。牛鼻水道至佛渡水道是一个潮流较强的潮通道;90%水交换周期为5天左右。象山港狭湾内水交换周期较长,湾顶处90%水交换的周期约为80天左右。  相似文献   
95.
The presence of the minimum salinity and oxygen-rich East Sea Intermediate Water (ESIW) off Korean coast has raised many questions about its origin and movement. This study attempts to answer these questions in the context of numerical model. For this, the Miami Isopycnic Coordinate Ocean Model is used with surface and inflow boundary conditions based on available data. Model results show that the ESIW forms most distinctly off Vladivostok, where the center of doming structure is observed, and moves southward along Korean coast forming a large cyclonic gyre around the doming. The renewed ESIW has the character of minimum potential vorticity common to usual mode waters. These results are compatible with various indications made in previous observational and theoretical studies. However, it is not known whether the doming structure is a result of convection or the latter is favored by the former. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
96.
Hydrocarbon top seal analyses are particularly difficult in fluvial and marginal marine settings. Although these settings often contain beds comprised of a low-permeability, clay-rich lithology associated with high quality seals, their presence does not guarantee an effective seal because individual beds within the stratal unit may be laterally discontinuous. Lateral facies changes, truncation of fine-grained beds, or the presence of crevasse splays may provide cross-stratal migration pathways, reducing the effective sealing capacity to a magnitude less than the closure height.  相似文献   
97.
In the Altiplanicie del Payún area (Neuquen Basin, Argentina), immature source rock sections intruded by up to 600 m thick Tertiary laccoliths show full spectrum maturity aureoles over hundreds of meters from the contacts. Commercial oil accumulations (20–33°API) and oil shows are located along the entire column, both in sandstone/carbonate and fractured igneous reservoirs. A challenging numerical model that included the emplacement of the intrusive bodies, with extreme temperature ranges and unusually short calculation time steps, has been done with the aim to better understand hydrocarbon generation and migration processes related to these thermal anomalies.  相似文献   
98.
In this paper we describe a 3D control-volume finite-element method to solve numerically the coupled partial differential equations (PDEs) governing geological processes involved in the evolution of sedimentary basins. These processes include sediment deposition and deformation, hydrocarbon generation, multiphase fluid flow, and heat transfer in deforming porous media.  相似文献   
99.
北部湾盆地涠西南凹陷C洼烃源岩热史及成熟史模拟   总被引:3,自引:0,他引:3  
北部湾盆地涠西南凹陷C洼流沙港组烃源岩热史及成熟史研究,对C洼深水油气勘探具有指导意义。在恢复涠西南凹陷C洼地史和热史的基础上,利用EASY%Ro模型计算了流沙港组烃源岩的成熟度史。研究结果表明,在涠西南凹陷发展的裂陷阶段初始期热流值较高,最大值约为77mW/m2,其后热流值逐渐减小,现今热流值约为54mW/m2;涠西南凹陷C洼流沙港组烃源岩开始生烃(Ro=0.5%)时间为51MaBP,达到生烃高峰(Ro=1%)时间为42MaBP,达到高成熟演化阶段(Ro=1.3%)时间为17MaBP;对比涠1井流沙港组烃源岩演化特征,处于C洼深水勘探区的流沙港组烃源岩成熟度较高,生烃能力较强,拥有广阔的油气勘探前景。  相似文献   
100.
Recent findings on water masses, biogeochemical tracers, deep currents and basin-scale circulation in the East/Japan Sea, and numerical modeling of its circulation are reviewed. Warming continues up to 2007 despite an episode of bottom water formation in the winter of 2000–2001. Water masses have definitely changed since the 1970s and further changes are expected due to the continuation of warming. Accumulation of current data in deep waters of the East/Japan Sea reveals that the circulation in the East/Japan Sea is primarily cyclonic with sub-basin scale cyclonic and anticyclonic cells in the Ulleung Basin (Tsushima Basin). Our understanding of the circulation of intermediate water masses has been deepened through high-resolution numerical studies, and the implementation of data assimilation has had initial success. However, the East/Japan Sea is unique in terms of the fine vertical structures of physical and biogeochemical properties of cold water mass measured at the highest precision and their rapid change with the global warming, so that full understanding of the structures and their change requires in-depth process studies with continuous monitoring programs.  相似文献   
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