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1.
Particular features of the tectonic structure and anomalous distribution of the geothermal, geomagnetic, and gravity fields in the region of the Sea of Okhotsk are considered. On the basis of heat flow data, the ages of large-scale structures in the Sea of Okhotsk are estimated at 65 Ma for the Central Okhotsk Rise and 36 Ma for the South Okhotsk Basin. The age of the South Okhotsk Basin is confirmed by the data on the kinematics and corresponds to a 50-km thickness of the lithosphere. This is in accordance with the thickness value obtained by magnetotelluric soundings. A comparative analysis of the model geothermal background and the measured heat flow values on the Akademii Nauk Rise is performed. The analysis points to an abnormally high (by approximately 20%) measured heat flow, which agrees with the high negative gradient of gravity anomalies. The estimates of the deep heat flow and the basement age of the riftogenic basins in the Sea of Okhotsk were carried out in the following areas: the Deryugin Basin (18 Ma, Early Miocene), the TINRO Basin (12 Ma, Middle Miocene), and the West Kamchatka Basin (23 Ma, Late Oligocene). The temperatures at the boundaries of the main lithological complexes of the sedimentary cover are calculated and the zones of oil and gas generation are defined. On the basis of geothermal, magnetic, structural, and other geological-geophysical data, a kinematic model of the region of the Sea of Okhotsk for a period of 36 Ma was calculated and constructed.  相似文献   

2.
The methods of perturbation theory and integral representations are used to analyze the general properties of a system of equations of the mechanics of inhomogeneous fluids including the equations of momentum, mass, and temperature transfer. We also consider various submodels of this system, including the reduced systems in which some kinetic coefficients are equal to zero and degenerate systems in which the variations of density or some other variables are neglected. We analyze both regularly perturbed and singularly perturbed solutions of the system. In the case of reduction or degeneration of solutions, the order of the system decreases. In this case, regularly perturbed solutions are preserved (with certain modifications) but the number of singularly perturbed components participating in the formation of the boundary layers on contact surfaces and their analogs in the bulk of the fluid, i.e., the elongated high-gradient interlayers, decreases. The interaction between all components of the currents is nonlinear, despite the fact that their characteristic scales are different.  相似文献   

3.
An attempt has been made to estimate the fishery potentials of the EEZ of India on the basis of data on primary and secondary production. The total column primary production and zooplankton production have been calculated to be 265·9 and 9 million tonnes of carbon per year, respectively. From these values the fishery potential has been estimated as 2·5 million tonnes per year. To this, if we add the estimated demersal fish catch, being 1·2 million tonnes per year, the total potential yield comes to 3·7 million tonnes per year. Since the present average total catch is about 1·6 million tonnes in a year, the fish catch could be doubled.  相似文献   

4.
G. N. Baturin 《Oceanology》2012,52(5):666-676
The lithology and geochemistry of the Miocene concretional phosphorites recovered from four submarine rises in the Sea of Japan (the North and South Yamato, the East Korean, and the Krishtofovich) were examined by means of analytical electron microscopy and ICP-MS chemical and microchemical elemental analysis. The microstructural studies and the data on the distributions of the 57 major and trace elements in these phosphorites revealed their close similarities to the Late Quaternary nodular phosphorites from the Namibian shelf, as well as phosphorites from other parts of the world, thus suggesting a common genetic affinity. Unlike the Namibian phosphorites, our samples collected from the Sea of Japan display a number of geochemical signatures indicative of volcanic and hydrothermal activity. This is supported by the presence of positive Ce and Eu anomalies in some samples and the Ga enrichment in a sample from the Chentsov Volcano.  相似文献   

5.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

6.
Aveiro is a town with 80,000 inhabitants situated in the central west coast of Portugal. It is located at the centre of the Ria de Aveiro, a coastal lagoon that functions as a multi-estuarine area. This town is crossed by several canals which are connected with lagoon channels through canal locks. The operation of the canal locks influences the hydro dynamism in Aveiro's canal and this and other human activities have left a sedimentary record. The study of these records was based on the sediments grain size and composition, mineralogy (by XRD techniques), geochemical (by ICP-MS), total organic carbon (TOC), and microfaunal (benthic foraminifera) content in 15 grab-samples collected in 2006 in Aveiro's canal. The total elemental concentrations evaluated by total digestion of the sediment fraction <2000 μm revealed the presence of “hot spots” of pollution caused by heavy metal contaminants in some Aveiro canals, related to legacies of past industrial activities. These “hot spots” have, for instance, higher available concentrations of Al, Cd, Co, Cu, Fe, Pb, Mn and Zn (evaluated by sequential chemical extractions) and are located in Paraíso, Alboi, Botirões and Cojo Canals, at sites where the sediments are finer and richer in TOC. Abiotic and biotic variables submitted to principal component analysis and cluster analysis highlights the hydrodynamics and human effects on the system and the negative influence of pollutants on the benthic organisms (foraminifera).  相似文献   

7.
A method for the estimation of the results of reconstruction of the trajectories of drifting buoys is proposed. It is based on the comparison of the estimates of power spectral densities for the components of current velocity computed according to three data sets: the data set of the coordinates of a drifting buoy with a built-in GPS receiver, the data set of coordinates formed on the basis of the first set but with data missing and observational errors corresponding to the actual trajectory measurements by the Argos satellite location and data collection system by the Doppler method, and the data set of coordinates obtained as a result of interpolation of the second set. As an example, we consider the procedure of realization of the proposed method and demonstrate the efficiency of its application for the improvement of the reliability of reconstruction of the trajectories of drifting buoys.  相似文献   

8.
介绍了海鸟系列温盐深测量仪(CTD)原始数据预处理的方法和步骤,解释各个过程中的原理,根据规范和工作实际对处理过程中存在的问题进行分析,提出解决方案,针对资料的标准化提出建议和意见。  相似文献   

9.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

10.
INTRODUCTIONThecontentsandtheirvariationofcellularbiochemicalcomponentsinnormallygrowingmarinealgaereflectthedifferenceinecologicalenvironments,reportedbymanyresearchers(MomsandSkea,1978;SmithandMoms,1980;LiandHarrison,1982;SmithandGeider,1985;Yangetal.,1991,1992).Lightintensity,temperatureandnutrientsaremostimPOrtantenvironmentalfactorsintheocean.ThispaperemphasizestheeffectsofenvironmentalfactorsonthecompositionofPhaendactylumtricornutum,Dunaliellaspp.,SkeletonemacostatumandIsOChr…  相似文献   

11.
为了研究泻湖型海湾内经常出现的湾中岛的形成机理,应用水平二维潮流、泥沙输移和地形演变耦合模型,对具有典型的沙坝泻湖地貌形态的水东湾的湾中岛的形成和演化进行了数值模拟,成功地模拟出了涨潮三角洲(大洲岛)的形成过程,计算结果与实际地貌形态总体符合。模型中分别考虑了全沙输沙和推移质输沙两种输沙情况。结果表明,水东湾湾中岛是由涨潮流引起的泻湖内泥沙不断淤积而形成的,是一种涨潮三角洲的地貌形态;全沙输沙模式比推移质输沙模式更适合这一地形演化过程的模拟。模拟结果也再现了湾中岛在25 a期间的地形变化过程,这一研究结果为通过计算数值模拟来研究一般海湾的地貌形态的形成机理和演化过程提供了实际算例。  相似文献   

12.
李四海  张峰 《海洋通报》2012,31(3):354-359
物联网是在互联网的基础上,利用信息技术实现物体自动识别和信息共享的网络系统。介绍了物联网发展的背景、体系结构及物联网的主要关键技术,分析了物联网的主要特征和内涵;在此基础上,介绍了有关国家物联网的发展战略和现状,并结合我国海洋领域的具体情况,提出了物联网技术影响下,我国海洋信息化发展的应对策略和技术路径。  相似文献   

13.
We have developed a parameterization of the dynamical and thermal effects of stationary orographic waves (SOWs) generated by the earth’s surface topography and included it into the general circulation model of the middle and upper atmosphere. We have analyzed the sensitivity of atmospheric general circulation at tropospheric to thermospheric altitudes to the impact of SOWs propagating from the troposphere. Changes in atmospheric circulation due to variations in the SOW generation and propagation have been considered for different seasons. It has been shown that, during solstices, the main dynamical and thermal impacts the middle atmosphere of winter hemispheres, where the SOW-induced changes in the velocity of zonal circulation can reach 30%. During equinoxes, the SOW impact is distributed more homogeneously between the Northern and Southern hemispheres, and the relative changes in the velocity of zonal circulation of the middle atmosphere may constitute 10%.  相似文献   

14.
《Oceanologica Acta》2002,25(5):213-218
Recent advances in physical oceanography, sampling and observation tools, and data management methods are sufficient to enable a wide range of organisms in the Gulf of Maine to be quantified and related both to other organisms and to the physical habitat. A pilot Census of marine life in the Gulf of Maine would advance the goals of ecosystem understanding and management in a timely manner. A prerequisite is knowledge of the distribution and abundance of the organisms that inhabit, both permanently and transiently, the Gulf of Maine and adjacent waters, namely those of Georges Bank, Browns Bank, and Slope Sea, including the New England seamounts. Both systematic and synoptic investigations of a spectrum of marine life are needed to supplement current data holdings, which, if extensive with respect to fish and certain marine mammals, are sparse with respect to the larger biogeography of the system. Technology offers the means of collecting and organizing such data. Efficiency in collection argues for dividing the spectrum of marine life into a number of functional groups, whose constituent organisms can be observed or sampled by the same or similar techniques. Five groups are identified: offshore subtidal benthos, intertidal and nearshore subtidal benthos, plankton, fish and squid, and large marine animals and seabirds. Associated tools of observation and sampling are listed and illustrated for two categories: high-frequency scientific echo sounders and underwater video microscopes. Parameters of the physical habitat are listed, and the power of the Gulf of Maine Ocean Observing System to define the physical oceanography is noted. Issues of data management, systems, and uses are described. Some benefits of a pilot census are noted. For the scientific community, these include making available biogeographic data that can support the formulation of data-based hypotheses. Testing these in the Gulf of Maine and adjacent waters may enable new knowledge of the particular ecosystem to be extended to distant ecosystems.  相似文献   

15.
在简要介绍AUV声学定位声纳接收机原理基础上,分析了CW脉冲信号在极性相关检测电路中的传输过程,建立了极性相关积分检测延时仿真分析模型。提出采用蒙特卡洛模拟方法获取检测延时的分布特征和统计参数的观点。实验结果表明蒙特卡洛模拟实验与硬件电路实验结果一致,对于解决随机性检测延时问题具有很强的能力。获得的结果可为AUV定位声纳检测门限的设定、声学测距和定位精度分析以及水声通信延时分析提供参考。  相似文献   

16.
目的:探讨人参醇提物及其沉淀对小鼠肠道菌群的影响。方法:利用环磷酰胺制备免疫低下小鼠模型,以人参水提物为对照,观察人参醇提物及其沉淀对小鼠肠道菌群的影响;肠道菌群数据采用Flash 1.2.11、Qiime 1.9.1、Mothur 1.30.2及PICRUSt 1.1.0等软件分析。结果:通过样本多样性指数分析,发现小鼠十二指肠、结肠、直肠所在部位肠道菌群结构差异具有统计学意义(P<0.05或P<0.01)。群落组成分析得知,小鼠肠道菌群差异较大的是Firmicutes(厚壁菌门),Bacteroides(拟杆菌门),Proteobacteria (变形菌门)与 Epsilonbacteraeota,Actinobacteria(放线菌门),Tenericutes(柔壁菌门)等。物种差异分析显示,免疫低下模型小鼠直肠部位的Epsilonbacteraeota数量显著增多(P=0.02),表明菌群失调;人参能调节肠道菌Epsilonbacteraeota失衡,其功效由大到小依次为人参水提物、醇提物及其沉淀。功能预测显示,肠道菌群结构改变,其对应的基因功能信息也改变,免疫低下模型小鼠直肠菌群结构与数量改变,引起RNA processing and modification, Chromatin structure and dynamics, Energy production and conversion 等方面基因改变。结论:免疫低下小鼠肠道菌群结构与功能改变,人参的不同提取物及其沉淀对小鼠肠道菌群有一定的影响。  相似文献   

17.
深海环境通常具有高盐,高压,高/低温,无光照等特点,使得海洋微生物存在一套独特的生理代谢机制和分子细胞结构,然而迄今绝大部分深海微生物不能在实验室条件下被分离培养,深海微生物资源开发遇到很大挑战。本研究通过不依赖培养的方法研究海洋微生物的基因资源,构建了南海深海沉积物fosmid宏基因组文库,共获得约39 600个克隆,插入片段范围在24~45 kb之间,平均插入片段大小为33 kb,克隆片段的总库容达到1 320 Mb。通过功能筛选获得3个具有淀粉酶活性的克隆子,选取其中最适温度较低的amy7作为进一步研究对象。构建amy7插入片段的重组质粒文库,获得一个同样有淀粉酶活性的克隆子amy7-6。经测序,克隆子amy7-6含有3 291 bp插入片段,序列比对分析后发现其中一个大小为1 920 bp的ORF,其编码的蛋白质序列(AmyS)与各种来源的糖苷酶有着较高的相似性。  相似文献   

18.
We propose to study the ecosystem of the plankton community of the euphotic shelf zone as a complex system with five hierarchical levels. To construct the computer image of the ecosystem, we use the methods of object-oriented modeling. The vital activity of the organisms of each species inside a certain conventional volume of water (basic object of the model) is described in detail. As a result, the entire system simulates the interaction of species in the analyzed ecosystem. The system combines four groups of biological elements (phytoplankton, bacteria, protozoa, and zooplankton) and biomineral elements (organic and mineral phosphorus) and includes the equations for the temperature of water and dissolved oxygen. The proposed numerical model reproduces the observed spotted character of the space and time distributions of the density of aquatic life and its activity. The data of the performed numerical experiments reveal the correspondence between the integral quantitative parameters computed in the model and the average characteristics obtained under natural conditions.__________Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 43–61, November–December, 2004.  相似文献   

19.
本文利用本海区的实测波浪资料,对波浪的基本特征、变化规律、风与浪的相关关系,以及工程中所需要的不同重现期设计波要素及波浪破碎范围等进行了统计、分析、计算,为本海区的近岸经济开发建设提供参考依据。  相似文献   

20.
The variations of the velocity and path of the Kuroshio are investigated by using the data obtained after the World War II. The time scales of these variations are classified into three categories,i.e. long-, medium- and short-terms. Period of the long-term variations seems to be about 7 to 9 years. Large meanders of the Kuroshio off Enshu-nada in 1953–1955 and 1959–1962 are accompanied with the low mean velocity of the Kuroshio. These large meanders are explained as a stationary Rossby wave by applying the equation for the phase velocity of the barotropic Rossby wave with the disturbance of finite width. To obtain the above conclusion, it is assumed that the Kuroshio extends down to the depth of 2,300 db and that the east component of the over-all mean velocity of the meandering Kuroshio should be substituted for the velocity of the eastward basic current in the above equation. As for the medium-term variation of the Kuroshio, there seems to exist variations in the velocity with the periods of 4, 6, 8 and 12 months and those in the position of the Kuroshio axis with the periods of 8 and 12 months. These meanders of the Kuroshio progress towards east with the mean phase velocity of about 5 miles a day, which is nearly the same as the calculated mean phase velocity of a progressive Rossby wave.  相似文献   

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