南黄海自生黄铁矿成因及其环境指示意义   总被引：12，自引：2，他引：12  

初凤友  陈丽蓉  申顺喜  李安春  石学法 《海洋与湖沼》1995,26(3):227-233

样品为１９８９年采自南黄海，利用显微镜，电子显微镜，电子探针和化学分析方法，对自生黄铁矿的形态，成份和同位素特征进行研究，在此基础上就其成因与形成环境的关系进行初步探讨。研究结果表明，自生黄铁矿集合体形态可以分为聚莓，单莓和细粒３种，霉体特征的形态是早期成岩作用阶段沉积物随机堆积的结果，可以作了沉积成因黄铁矿的形态标型黄铁矿微量成份特征显示其沉积成因，同时亦表现对泥质沉积物地球化学背景值的继承性，  相似文献   

琼州海峡铁路轮渡新海湾港区泥沙淤积问题     

沈莹  李大山  张镜潮  杨正己 《海洋工程》1997,(3)

海南省拟建琼州海峡铁路轮渡。本文通过对海峡南岸新海湾轮渡港址附近自然条件、岸滩演变和输沙特征的分析研究，对不同类型港区布置方案港内开挖区和航道的淤积强度、淤积量等进行了计算，并对不同防护建筑物的有效拦沙时间等进行了探讨和计算，提出了港区类型推荐方案。  相似文献   

黄河口及渤海中南部沉积物工程特性及其机理   总被引：3，自引：0，他引：3  

郑继民  沈谓铨  陆念祖  冯秀丽 《中国海洋大学学报(自然科学版)》1994,(2)

采用Ｋａｓｔｅｎ取样器从黄河口及渤海湾中南部海底沉积物中取样，对样品通过土工性质、微结构研究以及粘土矿物分析，阐明本研究区三维空间展布的海底沉积物形成机理及其工程地质规律，论证水动力作用和斜坡不稳定性对工程特性和微结构的重要影响．  相似文献   

Anomalous change of the Antarctic sea ice and global sea level change   总被引：3，自引：0，他引：3  

Xie Simei  Zou Bing  Wang Yi  Bao Chenglan 《海洋学报(英文版)》1996,15(2):193-208

ＡｎｏｍａｌｏｕｓｃｈａｎｇｅｏｆｔｈｅＡｎｔａｒｃｔｉｃｓｅａｉｃｅａｎｄｇｌｏｂａｌｓｅａｌｅｖｅｌｃｈａｎｇｅ￥ＸｉｅＳｉｍｅｉ;ＺｏｕＢｉｎｇ;ＷａｎｇＹｉａｎｄＢａｏＣｈｅｎｇｌａｎ（１．ＮａｔｉｏｎａｌＭａｒｉｎｅＥｎｖｉｒｏｎｍｅｎｔＦ...  相似文献   

On the radiation and diffraction of linear water waves by an infinitely long rectangular structure submerged in oblique seas   总被引：1，自引：0，他引：1  

Y.H. Zheng  P.F. Liu  Y.M. Shen  B.J. Wu  S.W. Sheng 《Ocean Engineering》2007,34(3-4):436-450

The radiation and diffraction of linear water waves by an infinitely long rectangular structure submerged in oblique seas of finite depth is investigated. The analytical expressions for the radiated and diffracted potentials are derived as infinite series by use of the method of separation of variables. The unknown coefficients in the series are determined by the eigenfunction expansion matching method. The expressions for wave forces, hydrodynamic coefficients and reflection and transmission coefficients are given and verified by the boundary element method. Using the present analytical solution, the hydrodynamic influences of the angle of incidence, the submergence, the width and the thickness of the structure on the wave forces, hydrodynamic coefficients, and reflection and transmission coefficients are discussed in detail.  相似文献   

Gradation affects basic mechanical characteristics of Chinese calcareous sand as airport subgrade of reefs     

Shen Yang  Xue Shen  Hanlong Liu  Huayang Ge  Xiaoxi Rui 《Marine Georesources & Geotechnology》2020,38(6):706-715

Abstract

Construction of the reefs in the South China Sea is a significant foundation to the secure stability and economic development of China. The construction of an airport runway is necessary for this realization. The calcareous sand is the main primary material in the runway construction. A certain type of calcareous sand near a certain reef of the South China Sea was studied in this paper. To investigate this specific calcareous sand, quartz sand was used as a reference for comparison. Microscopic 3-D imaging, compression and triaxial tests were conducted to test the micro, squeezing and shear properties. The effect mechanism of gradation on the calcareous sand’s compressibility and shear characteristics are discussed from a mesoscopic viewpoint using 3-D morphology. Calcareous sand particles are multiangular and flatter in comparison with quartz sand. The larger the particle sizes are, the more different the two sands’ morphologies are. The compressibility of calcareous sand is greater, and the effect of the coarse fraction (5–1?mm) content in the gradation plays the most significant role in this feature. When the coarse particles’ content is less than 25% and the mass ratio of the middle and fine particles (M) is constant, there is the worst coarse fraction content causing the calcareous sand to be most likely compressed. The worst coarse fraction content decreases with the increase in M, and an empirical formula is proposed. When the gradation, relative density and confining pressure are the same, the peak shear stress and strain of calcareous sand are all at a high level. The effect of confining pressure is manifested in calcareous sand. The shear strength and dilation of calcareous sand are also most affected by the medium coarse fraction (5–0.25?mm) content.  相似文献   

南极布兰斯菲尔德海峡表层沉积物的酸解烃   总被引：1，自引：0，他引：1  

卢冰  唐运千 《海洋学研究》1996,14(3):51-59

本文研究了南极布兰斯菲尔德海峡表层沉积物的酸解烃分布特征，并佐以热释汞和蚀变碳酸盐的分析。从酸解烃中甲烷含量的低值和Ｃ１／（Ｃ２＋Ｃ３）比值，以及乙烯的存在等判断，布兰斯菲尔德海峡沉积物的烃类气体来自于生物成因。  相似文献   

珠江口盆地基底结构的综合地球物理研究   总被引：15，自引：2，他引：15  

王家林  张新兵  吴健生  陈冰  钟慧智  郝沪军  李平鲁  苏乃容 《热带海洋学报》2002,21(2):13-22

通过对珠江口盆地重磁资料的分析处理及反演计算，依据盆地的地质、地球物理特征，采取了针对性的综合地球物理研究思路与方法，对地震资料难以解决的珠江口盆地基底结构进行了研究，确定了盆地的重力和磁性基底深度，并对盆地内的断裂和基底岩性作了推断，提供了新的认识，为今后研究提供了依据。  相似文献   

Neural network for wave forecasting among multi-stations     

Ching-Piao Tsai  Chang Lin  Jia-N Shen 《Ocean Engineering》2002,29(13):1685-1695

Unlike in the open sea, the use of wind information for forecasting waves may encounter more ambiguous uncertainties in the coastal or harbor area due to the influence of complicated geometric configurations. Thus this paper attempts to forecast the waves based on learning the characteristics of observed waves, rather than the use of the wind information. This is reported in this paper by the application of the artificial neural network (ANN), in which the back-propagation algorithm is employed in the learning process for obtaining the desired results. This model evaluated the interconnection weights among multi-stations based on the previous short-term data, from which a time series of waves at a station can be generated for forecasting or data supplement based on using the neighbor stations data. Field data are used for testing the applicability of the ANN model. The results show that the ANN model performs well for both wave forecasting and data supplement when using a short-term observed wave data.  相似文献   

凡纳滨对虾高密度养殖实验   总被引：3，自引：0，他引：3  

刘广斌  马甡 《海洋湖沼通报》2004,(3):54-58

实验时间 4 0天 ,放苗密度 5 0 0尾 /m2 、10 0 0尾 /m2 。凡纳滨对虾初体长为 2 .5 88±0 .341cm ,初体重 (0 .2 39± 0 .0 86 ) g。养殖水体中放置筛绢隔断 ,在不换水的条件下 ,监测水体中无机磷、氨氮的变化趋势 ,初步实验高密度和分隔养殖的效果。结果表明 ,高、低密度氨氮、无机磷差异均为极显著 (P <0 .0 1) ;成活率、产量差异均为显著 (P <0 .0 5 )。高、低密度特定生长率 体重 差异不显著 (P >0 .0 5 )。观察到不同时间不同密度凡纳滨对虾对筛绢隔断的反应不同 ,表明对虾能利用隔断筛绢 ,从而有效提高养殖容量  相似文献