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舟山册子岛-镇海段海底原油管道连续多年监测数据显示,局部海床冲刷较为严重,管道多处裸露、悬空,对工程安全构成威胁。基于Delft3D建立杭州湾口二维水流泥沙数学模型,并利用实测潮位、流速、流向及悬沙质量浓度资料对模型进行率定与验证,进而模拟分析近年来人为开发活动对海底管道附近海床冲淤变化的影响。分析结果表明,新泓口围垦工程和金塘大桥工程对管线镇海登陆段海床冲刷影响较大,金塘大桥桥墩阻水作用加剧了管线深槽边坡西半段海床的冲刷,另外管线深潭延伸东半段的海床冲刷与金塘大桥主通航孔密切相关。 相似文献
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海底管道是重要的能源生命线,海底管道路由上的采砂坑对管道在位稳定性造成严重威胁。为评估深港海底管道路由区域海流冲淤采砂坑对深港海底管道在位稳定性的影响,本文利用长期实测资料对比,并结合数值模拟方法分析海底管道路由上采砂坑冲淤问题,建立的有限元分析模型与实测资料能够较好吻合。研究得出波浪潮流作用下采砂坑的冲淤规律和未来十年的变化特征：采砂区内为淤积环境,北侧边界向西北方向扩展,远离管道走向,对管道无影响;南侧边界向东南方向扩展,造成铜鼓水道附近管道冲刷;东侧靠近管线段采砂坑坡顶受到侵蚀,导致采砂坑边界线向管线扩展。本文为深港海底管道路由采砂区海流冲淤分析提供了科学有效的方法。 相似文献
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根据路由勘察区水深测量、旁侧声纳、浅地层剖面探测等多项物理探测所获取的资料,结合其它自然环境及历史资料,对勘察区内海底工程地质条件进行了详尽的分析和研究．此外,还对近20a来勘察区海床稳定性进行初步分析,为选择一条最佳的路由通道提供依据．研究分析表明：可能影响该海缆安全运行的不良工程地质条件主要为海底灾害性地貌,如基岩、潮流冲刷槽等;勘察区不同区域内海底冲淤变化存在一定差异,潮汐通道底部受较强冲刷,冲刷速率为0．035～0．1m／a,20m以浅区域海底处于弱冲刷状态一冲淤动态平衡状态,冲刷速率为0．015m／a,海床较稳定;该路由勘察区工程环境较适合海缆的铺设,且其最佳路由区域是在勘察区南半部相对稳定的海底平滑区． 相似文献
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2012年2月3日,2011年下半年东海平湖油气田海管近岸段路由检测完工报告验收暨海管稳定性分析研讨会在上海召开。会议对由上海海洋石油局第一海洋地质调查大队承担的2011年下半年平湖芦洋岱衢海区海底管道路由检测项目进行了评审。 相似文献
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海底管道悬空防护与治理措施浅谈 总被引：2，自引：2，他引：0
为了治理一直困扰茂名30万t单点码头的海底管道悬空问题,首先分析了海底管道埋藏状态的识别方法,对国内外海底管线各种悬空治理措施的优缺点和适宜海域进行汇总。在对茂名30万t单点码头海底管道开展了多次路由调查的基础上,针对悬空路段,分别采用人工海草、沉排、碎石回填等不同的防护措施。结果表明,人工海草确实具有明显的降低流速和促进泥沙淤积的功能,但潜水员水下作业工作量较大,不宜在水深大于40 m的海域进行,应避开拖网捕捞海域。水泥沉排在水下较稳定,可有效保护海底管线免受外来损害,但是回淤促淤缓慢。当海床承载力足够时,采用碎石回填办法进行海管维护比较有效,冲刷坑填埋充实,可广泛用于修正悬空。 相似文献
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The correlation between the azooxantellate scleractinian coral distribution and the abundance of the zooplankton in the Atlantic
Ocean is discussed. The analysis is based on a dataset of 943 specimens (82 species) sampled at 87 stations that were performed
during the scientific cruises of Russian research vessels in the Atlantic. The hypothesis concerning if the coral biodiversity
and population density correlate with the zooplankton abundance was tested. The relationships between these parameters are
contradictory. High coral biodiversity and population density were registered for the areas of low and average zooplankton
abundance in the surface waters. 相似文献
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1982年第三次联合国海洋法会议产生了《联合国海洋法公约》,美国积极参与并主导了该《公约》的整个谈判过程,对《公约》大部分条款持支持态度,但最终却没有签署《公约》,其原因主要在于它反对《公约》第十一部分关于深海采矿的规定。1994年《执行(公约)第十一部分的协定》对《公约》中与深海采矿有关的部分进行了实质性修改,满足了美国的利益和要求,但美国国内对《公约》还存在其他一些反对意见。目前美国国内各界支持加入《公约》的呼声日益高涨,美国正在积极考虑加入《公约》。 相似文献
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Relationship between the path of the Kuroshio in the south of Japan and the path of the Kuroshio Extension in the east 总被引：2，自引：0，他引：2
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry
dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly
goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with
the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then
passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state. 相似文献
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为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明：黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km2,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km2;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。 相似文献
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射阳县位于江苏沿海中部，东临黄海，拥有海岸线长１０９ｋｍ，滩涂面积７万ｈａ，是江苏省渔业生产重点县之一。“九五”期间，射阳县把发展海洋渔业作为全县经济新的增长点来抓，不断加大开发力度，稳定提高捕捞业，全力突破养殖业，积极发展水产品加工业，取得显著成效，已成为海洋经济发展的先导产业和支柱产业，全县现有各类捕捞船只２０５８艘，总功率为７万多千瓦，海水养殖面积１万多公顷，育苗水体６５万ｍ３，水产品加工库容４０００余吨，年产各类海产品达５５万多吨。然而，在当前近海主要经济鱼类资源急剧衰退，伏季休渔期… 相似文献
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Analysis of the sections traversing the polar hydrological front on the shelf of the North-European basin has enabled us to reveal the areas limited by closed isotaches of the sound velocity existing in the interfrontal zone at depths of 50–150 m. These areas represent the closed waveguide which has the property of an underwater sound channel.Translated by Mikhail M. Trufanov. 相似文献
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Izvestiya, Atmospheric and Oceanic Physics - Analysis of the temporal variations of the virtual heights of the sporadic E layer (h?ES) determined from ionograms with increased accuracy (1... 相似文献
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Wei Shouqing 《海洋学报(英文版)》1991,10(3):480-480
A study was made on the polyculture of the red algae Gracilaria tenuistipitata Chang et Xia f. Liui Zhang et Xia, f. nov. , the shrimp Penaeus penicillatus Alcock and the mud crab Scylla serrata (Forskal) . The photosynthesis of the algae produces the oxygen on which the shrimp and the crab breathe. The algae are the reproductive place of the organism for the food of the shrimp and the carb, also is the shelter of the shrimp and the crab. The shrimp and the crab regard the algae as the vegetable 相似文献
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We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances
using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium
partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and
in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority
accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative
abundances of organic and inorganic carbon as an index of the carbon cycle stability. 相似文献
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The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ～200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ～380 km from the coast at a depth of ～250 m above the sea level. 相似文献