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介绍了浮球式海底取样器的结构,性能特点,典型应用及性能参数;论述了振动式振动冲击式贯入理论的原理;并分析了海流及船体飘移对海上取样作业的影响及解决办法。 相似文献
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从区域地质背景、岩石学、岩石化学、微量元素、氧同位素及稀土元素组成等方面论证东川铜矿含铜“礁—硅岩组合”中的含铜硅质条带—硅质白云岩为海底喷流热水沉积成因;提出了该类层状铜矿的深源含铜富硅混合热液海底喷流—生物富集的沉积成岩成矿模式。并提出东川落雪式层状“马尾丝”铜矿含矿岩系为“含铜礁—硅岩组合”的新观点。 相似文献
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20世纪海洋科学重大成果之一是伴随着深海科学研究、技术发展及海底矿产资源的勘查进程,发现并明确了深海底极端环境下的生物多样性。深海底生物多样性和基因资源管理问题已引起国际社会的广泛关注,也促使国际海底管理局①对正在制定的多金属硫化物和富钴结壳勘探规章提出更为严格的环境监测和评价的要求。介绍了深海底环
境及人类可能影响这一环境的有关活动;现有国际法律的适用性和国际社会正在采取的措施;我国应对的有关政策与措施。 相似文献
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海底电场传感器原理及研制技术 总被引:6,自引:1,他引:6
因海底电场信号微弱,海下自然环境复杂以及海水导电介质以氯离子为主等原因,用于海下电场测量的电场传感器在材料和结构上有其特殊性。研制海底电场传感器成为开展海洋大地电磁探测的重要技术内容之一。研制过程遇到的主要技术问题有;海底电极材料的选择;电极的制作工艺;承压与密封技术;海水运动对测量产生不利影响的克服办法;水下弱信号传输的抗干扰问题,等等,阐述了对上述问题的解决办法。提出了海底电场传感器的全套研制方案。并列举了相关的室内模拟实验和海洋试验的结果。 相似文献
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本文对我国的MB-2型和美国的TR-2型卵石推移质采样器的模型的水力特性和采样效率进行了对比试验研究。得到MB-2的水力效率为0.91,TR-2的水力效率为1.04;仪器置入水中后水流的紊动强度TR-2比MB-2大。TR-2的采校效率平均是MB-2的1.84倍,TR-2的采样效率方差平均是MB-2的1.67倍,即前者的采样效率比后者高,但其采样效率的稳定性比后者差。文中还给出了两种仪器的采样效率η 相似文献
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In this paper, an insight is provided into the quality of soil samples during the penetration of soil samplers. An updated Lagrangian finite element formulation with the second Piola–Kirchhoff stress rate (the Truesdell stress increment) to account for the large deformation behaviour near the sampling tube is used to determine the mechanical disturbances to a soft clay. The penetration of the sampler is simulated by splitting a group of nodes ahead of the penetration route up to a sufficient depth and applying incremental displacements to match the geometric configuration of the sampling tube. Consolidation effect is included to account for the rate of penetration. Thin-layer elements are added at the inside wall of the sampling tube to model the soil–sampler interface. The numerical results show that the central core of the sample is subjected to three distinct stages of vertical strain history, compression–extension–recompression, with the primary irrecoverable disturbances due to the compression stage ahead of the sampler. The degree of disturbance for a frictionless sampler was found to be constant after a penetration depth of 75 per cent of the sample tube diameter, while for a frictional sampler the degree of disturbances keeps increasing as the penetration proceeds. The results of a parametric study to determine the influence on sampling disturbances due to the rate of penetration, the thickness and the tip angle of the sample tube and sampler type are also presented. 相似文献
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A large-volume core sampler for sediment—muck substrates is described. The sampler can acquire a discrete sediment core of 10 cm in diameter and up to 1.5 m long. Such samplers are needed to collect the volume necessary for analysis of sediments for contaminants, bulk density, or radioactive dating. The sampler consists of a 1- to 2-m length of PVC pipe mounted below a threaded metal pipe air exhaust—intake assembly. This assembly is quick-connected to standard threaded lengths (300 cm) of water pipe (2 cm diam) or electrical conduit so that bottom sediments in water depths of up to 10 m can be sampled. The core sampler is hand-operated and pushed into bottom sediments from a boat. It does not have to be triggered remotely because of the one-way modified check valve in the air exhaust—intake assembly. After the sampler is extracted from the sediment, the extension handle can be quickly removed for ease of sampler handling, and the core can be extruded from the PVC tube by air pressure.Contribution of the National Sedimentation Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Oxford, Mississippi 38655, U.S.A. 相似文献
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介绍了在深埋、松散、流动、风化砂层中采取原状样的取样工具——TA89-64.8型原状样取砂器的结构和取样方法,并对该取砂器在我国长江三峡重大工程中的应用成果进行了分析 相似文献
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天然气水合物是一种潜力巨大的替代性能源,其可以稳定地存在于一定的低温高压条件之下。在天然气水合物钻探作业中,冷却保温技术是天然气水合物钻探的关键技术之一。低温可以抑制天然气水合物分解,这对获取水合物样品有着十分重要的作用。本文首先概述了海底天然气水合物取样器保温冷却技术研究现状,并对取样器冷却保温技术进行深入的调查研究和分析。然后对日本的PTCS取样器中的冷却保温技术和国内具有冷却保温功能的取样器进行了详细介绍,并对相关技术进行分析和总结,最后对海底天然气水合物取样器冷却保温技术的发展做了总结与展望。 相似文献
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An inexpensive, lightweight stream sampler is described which provides a method for continuous collection of suspended stream
sediments. The IS3* sampler collects integrated suspended stream samples, and because the sampler relies on basic sedimentation principles, it
can be deployed to collect suspended sediment stream samples for environmental studies or geochemical exploration in remote
areas. The sampler trapped from 0.45 to 1.2 g of dry sediment during 7- to 8-d field tests conducted during 1985. 相似文献