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利用声学浅地层剖面仪对海底管道在海底的赋存状态检测是确保海底输油气管道安全运行的重要措施之一。介绍了新型参量阵浅地层剖面仪SES-2000的基本原理及其特点,通过对福建湄洲湾LNG海底管道检测实际应用,有效识别出了埋藏、裸露和悬空等3类海底管道赋存状态,尤其对沙包回填治理后的管道埋深能有效探测识别。检测结果表明,该设备具有高分辨率和强穿透的特点,稳定性好,能获取高品质的管道检测数据,应用效果良好。获取的基础数据为海底管道日常维护提供了科学依据和技术支持。 相似文献
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海底管道在油气工业中发挥着重要作用,为保障其安全运营必须定期进行检测掌握其在海底的状态。有的海底管道在铺设时为其安全考虑,在海底管道上方覆盖了抛石等硬质保护层,这样就导致在海底管道定期检测时一些检测仪器难以探测到硬质保护层下海底管道的位置和埋深,而浅地层剖面仪和磁力仪仍然可以不同程度地实现这种情况下的海底管道检测。文中对浅地层剖面仪和磁力仪的原理进行了介绍并对其在上覆抛石等硬质保护层海底管道检测中的应用进行了分析探讨。分析结果表明浅地层剖面仪和磁力仪组成的综合检测系统对上覆硬质保护层的海底管道探测有一定效果,可查明海硬质保护层下海底管道的位置和埋深,为海底管道的安全管理和维护提供数据支持,也可为其他类似海底管道检测提供参考。 相似文献
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近年来,随着我国海洋资源的不断开发,越来越多的海洋油气资源采用海底管道(输油、输气等)输送到陆地.这些管道长期在水深较浅的海底中,容易受到风浪、潮流或其他外力作用,一旦发生悬空或断裂,不仅会造成大量的经济损失,而且可能产生重大的海洋污染,从而带来巨大的社会不良影响.因此,对海底管道定期检测非常重要.海底管道铺设后要进行检测,探明海底管道在海底的实际状态,查明受破坏的程度和位置,以便进行维护.通过分析表明,采用测深仪、SES-96声参量阵极浅地层剖面仪及侧扫声呐进行综合探测是比较有效的方法. 相似文献
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本文基于刚塑性极限分析理论,按照Hill塑性破坏模式,构建了砂性海床土体运动许可速度场。对饱和不排水砂性海床上浅埋圆形管道的极限承载能力以及管道的入泥深度进行了理论推导,给出了浅埋圆形管道承载能力与入泥深度的上限解答。同时,为了验证本文给出的承载能力和入泥深度上限解答的合理性,将计算结果与国内外规范中常用的Terzaghi等计算公式进行了对比分析。对比结果证实了本文上限解答与失稳模式较为合理。 相似文献
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营口市位于辽宁省的中南部,面对渤海的辽东湾,背依鞍山市平原丘陵,东邻辽东崇山峻岭,西接盘锦市沿海平原,有辽河蜿蜒人海,海岸线绵延曲折。由于受海洋、河流的影响．营口市四季分明,气候宜人,蕴藏着丰富的滨海旅游资源,海蚀景观、地质珍迹、人文景观等资源各显异彩;尤其是海水浴场,条件极为优越,与国际上一流的海水浴场相比．毫不逊色,在某些特征上还稍胜一筹。 相似文献
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A. P. Tolstosheev 《Physical Oceanography》2009,19(6):358-365
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
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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
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1992年，联合国21世纪议程提出了综合管理的概念，并认为它是海岸管理的最重要目标，而海岸管理的目的就是改进业已存在的管理实践的效率和效果。在21世纪议程的实施过程中，沿海国家面临着巨大的困难，即：为了使综合管理在实践中具有可操作性而建立适合的政府机构。韩国正是在国家范围和次一级区域进行这项工作的实验场所。这项工作的最重要成就是在1996年成立了具有综合协调各涉海部门职能的韩国海洋事务与渔业部（MOMAF）。这篇文章的内容主要来自于这些观察，即韩国政府为建立海岸带综合机制而进行了各种努力，特别是1992年联合国环发大会召开后到1997年初海洋事务与渔业部成立了海岸带管理处这段时间里开展的各种工作，文章重点在于评价在建立海岸带综合机制的过程中综合的概念是如何被应用并被挑战的。文章提出了在东亚地区沿海国家开展合作的可能区域的建议。 相似文献
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天然气水合物地球化学特征 总被引：4，自引：0，他引：4
天然气水合物是在低温、高压以及有足够气体供应条件下形成的一种天然气(主要为甲烷)与水组成的似冰状固态化合物。天然气水合物中包含的甲烷碳是全球甲烷资源的重要组成部分,是一种数量巨大的潜在能源[1]。而且由于甲烷的温室效应,天然气水合物分解释放的甲烷进入大气中会严重 相似文献
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I. E. Timchenko A. A. Primalenny V. D. Yarin E. F. Vasechkina E. M. Igumnova 《Physical Oceanography》2001,11(4):367-378
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
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Values of root mean square slope 0 and its variations -0 are estimated using the brightness field of an image of the surface of the sea near a speck of light. When 0 and -0 are defined it is highly important to take into account direct as well as dissipated solar radiation.The space-time analysis of the structure of the image brightness field is performed. This gives an opportunity to estimate dispersion relationship and the running effect of a brightness contrast packet. Comparison of the parameters obtained with the theoretical dispersion ratio of internal waves (IW) allows one to make a conclusion that IW surface manifestations are recorded in a frame.UDK 551.463.5 相似文献
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Yu. D. Chashechkin 《Physical Oceanography》2011,20(5):317-324
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