Computation of Diffraction of Irregular Waves Behind Double Jetty

The coefficient of deffraction of regular waves behind the double jetty has been computed in this paper at first by using the singularity distribution method. The model tests conducted for diffraction of irregular waves with a unidirectional frequency spectrum have confirmed good agreement between the data measured in experiments and the results computed by the singularity distribution method plus the linear superposition method for the energy of component waves in the directional frequency spectra. Therefore, this technique for component waves in the directional spectra has been further used to compute diffraction of irregular waves of multidirection, including the employment of a directional distribution function of the cos2 type, as well as the Bretschneider-Misuyann frequency spectrum.     

Ultimate Bearing Capacity of Subsoils to Marine Pipelines

- Based on the theory of limit analysis, the Finite Difference Method (FDM) is established for evaluating the ultimate bearing capacity of subsoils to bear the unburied pipelines. The analytical results of bearing capacity of the ideal clay is given. The approach to bearing capacity evaluation of cohesionless subsoils without surcharge is suggested. The results from this method are consistent with those obtained from model tests.     

Application of Random Process in Soil Profile Modeling

When using the random process in soil profile modeling, the stationary and ergodicity of thesoil properties in the profile must be tested. This paper describes a procedure for stationary and ergodicity testing. Numerical examples were given for demonstration. A log-cosine function is suggested to simulate the correlation function, which has been proved to be good for soil profile modeling.     

The Importance of Computational Grids in Hydraulic Numerical Models

The importance of computational grids in hydraulic numerical models is studied by numericalsimulation of jet flow in a rectangular duct which is linked with a fixed width inlet and a different widthoutlet using a standard k-ε turbulence model.The computational results show the numerical solutionsmay not be reasonable because of the incorrect computational grid and each numerical model has a grid-in-dependent solution.The computational grid has a definitive effect on the accuracy and stability of thecomputational solution,which must be divided well according to the simulated geometry and physicalcharacters of hydraulic problems.The main guidelines about the formation of computational grid in suchaspects as node distribution,smoothness and skewness of grid,have been given.     

中国地震局地球物理研究所科技期刊网站开通运行

通过中国地震局地球物理研究所基本科研业务专项基金的支持和地球物理研究所科技期刊编辑室全体编辑人员的共同努力,中国地震局地球物理研究所科技期刊网站（http：／／www．sjst．org．cn／）现已开通运行。     

中国气象科学研究院及专业研究所2008年度学术年会隆重举行

“中国气象科学研究院及专业研究所2008年度学术年会”2009年2月12-13日在广东省清远市隆重举行。来自中国气象局科技发展司、中国气象科学研究院和局8个专业研究所、各省市气象局、大专院校等24个单位的领导和专家学者150多名出席了会议。     

2010年度国家自然科学基金项目指南(地球科学部分)

面上项目指南 地球科学是人类认识地球的一门基础科学.他以地球系统及其组成部分为研究对象,探究发生在其中的各种现象、过程及过程之间的相互作用,以提高对地球的认识水平,并利用获取的知识为解决人类生存与可持续发展中的资源供给、环境保护、减轻灾害等重大问题提供科学依据与技术支撑.人类对地球奥秘的探索精神,社会经济发展对资源利用,以及生活质量的提高对环境保护和自然灾害防治的日益增长的巨大需求,始终是地球科学发展的驱动力.地球科学的分支学科包括地理学、地质学、地球化学、地球物理学与空间物理学、大气科学、海洋科学等.     

我国资源潜力、趋势与对策

Symposium on potentiality, tendency and countermeasures of our country resources was convened by the Geoscience Division of Chinese Academy in Beijing in April 14-17, 1991. In the symposium, the present situation, exploiting potentiality in future and countermeasures of mineral resources, energy resources, land resources, water resources,living things resources,climate resources,human resources, marine resource and tourism resources were discussed detailed.
In this report, scientists who joined the symposium have analysed the characteristics and circumstances of our country resources, and discussed its potentiality, put forward that our country should establish the national economic system of resources-saving. At last the development strategy and fundamental countermeasures of our country have given.     

东海陆架盆地丽水凹陷丽水36-1构造上古新统物源分析

丽水36-1构造位于东海陆架盆地(台北坳陷)丽水西次凹的中东部，该凹陷属新生代断陷型盆地，呈北东向展布，上古新统灵峰组和明月峰组是主要目的层段。根据该构造已钻3口井进行系统沉积学和测井相研究，上古新统物源主要来自凹陷西部的闽浙隆起带和中部的灵峰凸起带，可能还有北部的雁荡凸起带。不同的物源区通过断层的活动和海平面的升降等控制着沉积体系的发育和展布。在凹陷下陷兴盛和海平面快速上升期，灵峰凸起带物源经过边缘大断层在其西侧形成扇三角洲，进一步向凹陷中心推进形成深水浊积扇和浅海沉积；闽浙隆起带物源可能沿着不同的入口在凹陷西斜坡形成扇三角洲，它们也可进一步向凹陷深处推进形成深水浊积扇体。根据油气聚集规律和物源分析，形成于凹陷深水区的浊积扇沉积和斜坡带的扇三角洲前缘沉积，具有良好的生储盖组合，是有利的勘探目标。