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11.
利用海洋模态重构方法对LEVITUS数据库数据进行了分析,获得了中国近海的温度、密度和声速的最大跃层强度及其深度的月平均变化规律.海洋要素的最大跃层强度在7、8月份达到最大,而且分布均匀,最大跃层强度对应的深度为全年最浅.12月至次年3月的最大跃层强度最小,分布杂乱,最大跃层强度对应的深度为全年最深.其他月份的分布介于二者之间.  相似文献   
12.
The US Minerals Management Service (MMS) is responsible for safe and environmentally sound management of offshore oil and gas resources. In recent years, there has been a tremendous increase in both activities and plans for deepwater development of these resources in the Gulf of Mexico (GOM). As the industry meets the enormous technical challenges involved, there is a concomitant effort to assure environmental protection of deep-ocean and coastal resources. This paper will outline the research planning and program currently underway to assess impacts, identify potential problems, and discover more about unknown resources of the deep ocean.  相似文献   
13.
论文在提出海洋和“新海洋”广度、深度空间概念的基础上,进一步诠释了作为新的海洋权益的控制权,及其在未来政治、经济、外交、军事等领域的重要作用。由于海洋蕴藏着巨大的可再生能源,论文从能源开发利用的视角分析了开发利用海洋深度空间的重要战略意义,并对解决我国海洋争端,开发海洋新能源及综合践行海洋深度空间权战略提出了应对策略。  相似文献   
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15.
In order to make use of ocean clay reasonably and excavate its potential applications the properties of ocean clay in Chinese investigating area of the East Pacific have been tested with the chemical analysis, XRFS, ICP/MAS, granulometry and SSA, etc. The results show that the clay sediments of this area are rich in clay minerals, fine granularity, bigger SSA, bigger water absorbability and lower ion changing ability etc. To improve the adaptability of ocean clay and macromolecule materials, using the dry milling method with silane, aluminate, stearic acid coupling agents etc the properties of ocean clay are improved. The effect has been evaluated by testing the water absorbing of the modified ocean clay and their dispersing in paraffin liquid. The result is that KH550 is better than any other active reagents, and the best activation technics is that 1.5% (volume) of KH550 quantity, 20min of milling time. The DTA, XRD, SEM and IR analyses and SSA testing show that the organic activation can not change the mineral structure but can densify the structure of clay, and activation mechanism is chemical covered mainly and chemical combined secondly.  相似文献   
16.
Open boundary conditions (OBCs) for a regional ocean model that can be integrated stably over a long timeframe, as well as satisfy the volume, heat and salinity conservation constraints, were developed. First, the idea that the inward and outward flux information can be treated separately in the OBCs was adopted. Second, in order to maintain the property that the volume, heat and salinity remains conserved in the simulation domain, conservation constraints were added to the OBCs, and an inverse method utilized to solve the constraint equations. Ideal experiments were designed to investigate the conservation property, and the OBCs were found to work efficiently to maintain the volume, heat and salinity conservation. It was found that simulations were comparable to observations when the OBCs were applied to a regional ocean model.  相似文献   
17.
Time-series data on upper-ocean temperature, Vessel-Mounted Acoustic Doppler Current Profiler (VM-ADCP) measured currents and surface meteorological parameters have been obtained for the first time in the southern Bay of Bengal at 7‡N, 10‡N, and 13‡N locations along 87‡E during October–November, 1998 under BOBMEX-Pilot programme. These data have been analysed to examine the diurnal variability of upper oceanic heat budget and to estimate the eddy diffusivity coefficient of heat in the upper layer. Diurnal variation of near-surface temperature is typical at northern location (13‡N) with a range of 0.5‡C while the diurnal range of temperature is enhanced to 0.8‡C at the central location (10‡N) due to intense solar radiation (1050 W/m2), clear skies and low wind speeds. At the southern location (7‡N), the diurnal variation of temperature is atypical with the minimum temperature occurring at 2000 hrs instead of at early morning hours. In general, the diurnal curve of temperature penetrated up to 15 to 20 m with decreasing diurnal range with depth. The VM-ADCP measured horizontal currents in the upper ocean were predominantly easterly/northeasterly at southern location, north/northerly at central location and northwesterly at northern location, thus describing a large-scale cyclonic gyre with the northward meridional flow along 87‡E. The magnitudes of heat loss at the surface due to air-sea heat exchanges and in the upper 50 m layer due to vertical diffusion of heat are highest at the southern location where intense convective activity followed by overcast skies and synoptic disturbance prevailed in the lower atmosphere. This and the estimated higher value (0.0235 m2/s) of eddy diffusivity coefficient of heat in the upper ocean (0–50 m depth) suggest that 1-D processes controlled the upper layer heat budget at the southern location. On the other hand, during the fair weather conditions, at the central and northern locations, the upper layer gained heat energy, while the sea surface lost (gained) heat energy at northern (central) location. This and lower values of eddy diffusivity coefficient of heat (0.0045 and 0.0150 m2/s) and the northward intensification of horizontal currents at these locations suggest the greater role of horizontal heat advection over the 1-D processes in the upper ocean heat budget at these two locations.  相似文献   
18.
本文提出了一种以FIOUGH变换为基础的海浪波长波向分析法,并对SEASAT合成孔径雷达获取的海洋遥感图像进行了方向和波长分析。该方法模拟人类纹理视觉机理,首先应用CFCM动态聚类方法对波峰、波谷和过渡带进行分类,然后采用随机行走模型对分类图像进行滤波,以获得整图的全局走向信息,再以此先验信息为先导对分类后的纹理图像进行定向跟踪拟合,得到代表海浪波峰的直线族图,最后在再对此图进行HOUGH变换和分析的基础上得到精确的波长与波向。  相似文献   
19.
1. Introduction It is well-known that the state of ocean plays very important role in the climate change. But there is a paucity of the ocean observation data. The data distri- bution in the space, time and different components is very inhomogeneous, even in some areas, there are no any observation data. Hence, it brings some diffcul- ties to the scientists to study many problems relevant to ocean. This situation has been being changed since ARGO (Array for Real-time Geostrophic Oceanogra-…  相似文献   
20.
四川盆地东北部长兴期沉积特征与沉积格局   总被引:64,自引:1,他引:64  
四川盆地东北部长兴组(大隆组)为海洋环境的产物,根据沉积特点,可以分为碳酸盐台地沉积体系和盆地沉积体系。碳酸盐台地沉积体系又可进一步分为局限台地、开阔台地、台地边缘礁滩及缓坡等沉积相。在详细研究分析各沉积体系的沉积特点的基础上,探讨了该期沉积相带的空间分布,提出了不存在“开江一梁平”海槽的认识。笔者等认为在“开江梁平海槽”区域内,长兴组只是水体相对台地较深环境(台棚环境)的产物,为碳酸盐缓坡,不宜称为海槽。指出台地边缘浅滩及生物礁是储层最有利相带,礁白云岩及颗粒白云岩等是储层的有利微相。研究区的生物礁为碳酸盐台地边缘缓坡点礁群,沿着台地边缘断续分布。  相似文献   
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