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881.
Liwen Chen Wu-Cheng Chi Char-Shine Liu Chun-Tien Shyu Yunshuen Wang Char-Yu Lu 《Marine Geophysical Researches》2012,33(4):379-388
Fluid migration rates are important parameters for understanding the structural characteristics and evolution of the crustal tectonics and hydrocarbon exploration. However, they are difficult to measure on the seafloor. Densely sampled temperature measurements might shed light on our study of the fluid migration rates. In this study, we first use reflection seismic data to derive geothermal gradient patterns at different sub-seafloor depths, then calculated 1D vertical fluid flow models by analyzing the Péclet numbers in the offshore regions of SW Taiwan. We found Péclet numbers ranging from 2 to 5, implying that vertical fluid flow velocities are between 6 and 44 cm/year. Assumed a homogenous permeable layer and no lateral variation of the temperature fields, we analyzed possible errors caused by depth-dependent thermal conductivity and velocity-depth function. They probably cause less than 2 cm/year of errors in the estimated vertical fluid flow rate. In terms of regional fluid flow patterns, we found higher fluid flow rates near the toe of the trench, and a dramatic increase in fluid flow rate when the continental slope of the Chinese passive margin enters into the trench, and reduced fluid flow rates in the hinterland. We propose that this is a new and potentially useful method to derive regional fluid flow rate models for studying geochemical and biological processes in shallow seafloor sediments and the regional hydrological budget. 相似文献
882.
Xiangchun Wang Timothy A. Minshull Changliang Xia Xuewei Liu 《Marine Geophysical Researches》2012,33(4):389-396
It is very important for converting the seismic data from the time domain to the depth domain. Here we discuss the approaches of inverse modeling of travel times for determination of the P-wave velocity (Vp). The migration section of the single channel seismic data is used to define the model horizons and help to control their geometry. Wide angle hydrophone data of OBS are used to determine P-wave travel times. The picked travel times from various shots are inverted for P-wave interval velocities using RayInvr, which calculated theoretical travel times via ray tracing. Damped least squares optimization is performed to fine tune the fits between observed and calculated travel times. In the end, the Vp curve is achieved and the results are compared with that derived from the conventional hyperbolic curve velocity analysis method, the shape of the two curves are similar, and the velocity increases in the layer where gas hydrates are present. 相似文献
883.
884.
海洋浮游植物的生物富集热力学模型——对疏水性污染有机物生物富集双箱热力学模型 总被引:4,自引:0,他引:4
依据疏水性有机物(HOC)在有机相/水相之间简单物理化学分配的基本原理,提出了浮游植物对HOC生物富集双箱热力学模型。得出浮游植物对HOC的生物富集因子BCF与浮游植物比表面积S,有机物正辛醇/水分配系数kow,有机物在水中浓度Cw之间皆存在log-log相关性的结论,并且由海洋浮游植物对氯代苯的生物富集实验结果验证了该模型。 相似文献
885.
994年9月采集了珠江口表层海水水样,并对其溶解态的K+、Na+、Ca2+、Mg2+、SO2-4、Cl等化学要素进行了测定。结果表明,珠江口调查海域表层水中溶解态的K+、Na+、Ca2+、Mg2+、SO2-4主要受陆源淡水与外海水物理混合稀释的影响,与Cl具有良好的直线正相关;Ca2+/Cl、SO2-4/Cl明显高于大洋水相应比值,Na+/Cl、Mg2+/Cl略高,而K+/Cl比大洋比值低;在与中国其它各主要河口表层水对应Cl比较中,珠江口的SO2-4/Cl较高,而Ca2+/Cl,Mg2+/Cl比值居低;上述各主要常量离子和Cl的等值线均沿自北向南走向递增。 相似文献
886.
AnumericalpredictionmodelofstrongthermoclineintheBohaiandtheHuanghaiSeasWangZongshan,XuBochang,JinMeibing,ZouEmei,LiFanhua(Re... 相似文献
887.
Numericalstudyofpollutanttransportinthesea-baywithmildslopebeachWangZeliangandTaoJianhua(ReceivedDecember22,1996;acceptedJanu... 相似文献
888.
889.
Zhang Yonggang Li Yucheng Associate Professor Dept. of Mechanic Engineering Shanghai Jiao Tong University Shanghai Professor Dept. of Civil Engineering Dalian University of Technology Dalian 《中国海洋工程》1998,(1)
A nonlinear numerical model has been set up by use of Boussinesq Equation with finite differ-ence method,and has been applied to the simulation of the abnormal change of wave height induced by ex-cavated waterway.Numerical results demonstrate that the abnormal change of wave height is due to theadding of the reflected wave height induced by excavated waterway to the incident wave height.Becausethe angle between the incident wave and the axis of the waterway is smaller than the critical angle,the re-flected wave produced by the waterway may propagate to the breakwater and may be added with the inci-dent wave,then the abnormal change of wave height before the breakwater may be caused.So the wave re-flection caused by the change of water depth cannot be neglected. 相似文献
890.
中华鳖气单胞菌疖疮病的研究 总被引:5,自引:0,他引:5
气单胞菌疖疮病是中华鳖的主要病害之一,其发病对象主要是稚鳖。将病鳖进行细菌分离,获得的菌株经人工感染、毒力测试和细菌学鉴定,确定致病菌为嗜水气单胞菌Aeromonashydrophila与豚鼠气单胞菌A.caviae。此两种致病菌不仅对健康鳖表现出较强的致病力,出现与自然病鳖相同的症状,且对健康小鼠亦有较强的致死力,半致死量LD50分别为4.5×106个菌/只和1.58×106个菌/只。此外,测定了病原菌对抗生素的敏感性,为科学防治提供依据。 相似文献