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《海洋地质与第四纪地质》编辑部 《海洋地质与第四纪地质》2000,20(1):38
千禧龙年 ,一个充满希望的 2 1世纪拉开了帷幕 ,人类社会又将奏响科学技术进步的新乐章 ,一个崭新、灿烂的新时代等待我们再创辉煌。《海洋地质与第四纪地质》2 0 0 0年以新的形象与您见面了 ,这是读、作者高层次的需要 ,也是时代发展的必然 ,我们诚望继续得到广大读、作者和社会各界的支持与厚爱。同时 ,也希望《海洋地质与第四纪地质》生机似龙腾 ,新世纪有一个良好的开端。《海洋地质与第四纪地质》新版本为大 1 6开 ,彩印封页 ,设置 :院士论坛 (不定期 )、沉积与环境、地球化学与地球物理、古海洋与年代地质、油气与矿产、第四纪地质、… 相似文献
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海域法正式实施了,在某种意义上,这对海洋管理工作是一个全新的开始。良好的开端是成功的一半。新法实施的第一步该怎么走?头怎么开?可以说至关重要,因为它关系到以后的工作怎么做,能不能打开局面,建立一个良好的执法环境,打下一个坚实的工作基础。当前我们要做的工作千头万绪,但其中一件重要的事情就是如何理清思路,走好第一步。这既是眼下大家最关注的,也是各级海洋管理部门应该认真思考的问题。首先,需要认清我们面临的形势,掌握工作主动权。这对于把握整个工作方向和制定相关对策有重要意义。近年来国家对海洋工作高度重视… 相似文献
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Carl H. Hobbs C. Scott Hardaway C. R. Berquist 《Marine Georesources & Geotechnology》2013,31(2-3):155-163
Virginia's year 9 and year 10 funds from the Continental Shelf Program were used to supplement other work funded by the Minerals Management Service in an ongoing Cooperative Agreement focused on the area offshore of southeastern Virginia. Year 9 and year 10 funds facilitated interpretation of subbottom profiles and the analysis of sediment samples from cores and grabs. On Virginia's sediment-starved continental shelf, deposits of material potentially suitable for use as beach nourishment or, perhaps, as construction aggregate occur in three stratigraphic settings, each with specific characteristics of morphology, grain-size gradients, likelihood of discovery, and physical ease of exploitation. All must be verified with a careful program of coring. Modern shoals generally are easier to identify, prove, and access than either filled channels or lenticular facies. Shoals usually are identifiable on nautical charts and characteristically have a definite lower boundarythat can be seen in subbottom profiles. In most cases, the base of the shoal coincides with the level of the surrounding sea floor. Filled channels are readily identifiable on subbottom profiles but may have a narrow, sinuous form and steep lateral gradients in sediment properties. Buried lenticular facies of good-quality sand usually are found only fortuitously. As the lateral and often vertical gradients in geotechnical properties usually are low, the lenticular facies can be mined with a lesser concern for the consequences of violating the deposit's limits than with the other two types of deposit. There are three types of filled paleochannels in the study area. (1) Relatively near-surface, generally small, roughly shore normal channels most likely mark the migration of tidal inlets across the shelf during the most recent transgression. (2) Small, relatively wide and relatively shallow generally shore parallel channels may be filled back-barrier or lagoonal channels. (3) Larger channels trending across the shelf probably result from riverine flow. The complexity of the seismostratigraphy of the Quaternary deposits on south eastern Virginia's inner continental shelf is a result of series of high-frequency (fifth-order, 10-20,000 y), low-amplitude (20-30 m) variations in sea level that occurred during the last highstand, roughly 80,000 to 130,000 BP. The evidence of the small oscillations in sea level is best seen in the regions that were between the shoreline and wave base, today's inner shelf; however, the very low rates of deposition on the shelf make it difficult to correlate specific reflectors or beds or, at times, to distinguish between fifth-and fourth-order changes. Results for the continuing studies already have been used in the determination to mine several hundred thousand cubic meters of sand from Sandbridge Shoal for use on a Navy-owned facility and in consideration of mining greater quantities of sand from Sandbridge and other shoals for use in local beach nourishment and hurricane protection efforts. 相似文献
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Carl H. Hobbs C. Scott Hardaway C. R. Berquist 《Marine Georesources & Geotechnology》1999,17(2):155-163
Virginia's year 9 and year 10 funds from the Continental Shelf Program were used to supplement other work funded by the Minerals Management Service in an ongoing Cooperative Agreement focused on the area offshore of southeastern Virginia. Year 9 and year 10 funds facilitated interpretation of subbottom profiles and the analysis of sediment samples from cores and grabs. On Virginia's sediment-starved continental shelf, deposits of material potentially suitable for use as beach nourishment or, perhaps, as construction aggregate occur in three stratigraphic settings, each with specific characteristics of morphology, grain-size gradients, likelihood of discovery, and physical ease of exploitation. All must be verified with a careful program of coring. Modern shoals generally are easier to identify, prove, and access than either filled channels or lenticular facies. Shoals usually are identifiable on nautical charts and characteristically have a definite lower boundarythat can be seen in subbottom profiles. In most cases, the base of the shoal coincides with the level of the surrounding sea floor. Filled channels are readily identifiable on subbottom profiles but may have a narrow, sinuous form and steep lateral gradients in sediment properties. Buried lenticular facies of good-quality sand usually are found only fortuitously. As the lateral and often vertical gradients in geotechnical properties usually are low, the lenticular facies can be mined with a lesser concern for the consequences of violating the deposit's limits than with the other two types of deposit. There are three types of filled paleochannels in the study area. (1) Relatively near-surface, generally small, roughly shore normal channels most likely mark the migration of tidal inlets across the shelf during the most recent transgression. (2) Small, relatively wide and relatively shallow generally shore parallel channels may be filled back-barrier or lagoonal channels. (3) Larger channels trending across the shelf probably result from riverine flow. The complexity of the seismostratigraphy of the Quaternary deposits on south eastern Virginia's inner continental shelf is a result of series of high-frequency (fifth-order, 10-20,000 y), low-amplitude (20-30 m) variations in sea level that occurred during the last highstand, roughly 80,000 to 130,000 BP. The evidence of the small oscillations in sea level is best seen in the regions that were between the shoreline and wave base, today's inner shelf; however, the very low rates of deposition on the shelf make it difficult to correlate specific reflectors or beds or, at times, to distinguish between fifth-and fourth-order changes. Results for the continuing studies already have been used in the determination to mine several hundred thousand cubic meters of sand from Sandbridge Shoal for use on a Navy-owned facility and in consideration of mining greater quantities of sand from Sandbridge and other shoals for use in local beach nourishment and hurricane protection efforts. 相似文献
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On Seasonal and Year to Year Variation in Flow of the Alaskan Stream in the Central North Pacific 总被引:1,自引:0,他引:1
The Alaskan Stream is the westward boundary current of the North Pacific subarctic gyre. In the central region of the North Pacific, the Alaskan Stream serves as a connection between the Alaskan gyre, Western subarctic gyre and Bering Sea gyre. Its volume transport is very important in estimating the magnitude of the subarctic circulation in the North Pacific. In order to clarify its seasonal and interannual variation, we conducted observations along a north-south section at 180° during June from 1990 to 1997. Moorings were deployed from 1995 to 1997. Hydrographic casts were made at intervals of 37 km to a depth of 3000 m. Moorings were set between CTD stations, with Moor1 (Moor2) at the center (southern edge) of the Alaskan Stream. Geostrophic volume transport (referred to 3000 m) revealed large interannual variability in the Alaskan Stream. Average volume transport over the 8 years was 27.5 × 106 m3s-1 with a standard deviation of 6.5 × 106 m3s-1. Maximum transport was 41.0 × 106 m3s-1 (1997) and minimum was 21.7 × 106 m3s-1 (1995). Stable westward flows were observed at Moor1 1500 m (259°, 11.7 cm s-1) and 3000 m (240°, 3.7 cm s-1, 1996–1997 year average). The ratio of eddy to mean kinetic energy (KE/
) was very small (<0.6) throughout the year. A relatively weak and unstable westward flow was observed at Moor2 at 3000 m depth. Conversely, the average flow direction at Moor2 5000 m was eastward. 相似文献
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1 前言 福建是我国一个海洋大省,海域辽阔,海岸线蜿蜒曲折,全省拥有200米等深线范围内海域面积13.6万平方公里,比陆地大12%左右,海岸线总长3051公里,滩涂面积2068平方公里,拥有大小岛屿1546个,大小港湾125个,海洋资源十分丰富。地 相似文献
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▲上海水产大学鱼类标本室被定为上海市科普教育基地 在最近召开的上海市科普工作会议上,上海水产大学鱼类标本室被命名为"上海市水生生物科普教育基地".鱼类标本室由已故著名鱼类学家朱远鼎教授于1952年创立,经过一代一代的研究和工作人员的整理补充,目前已收藏了国内外鱼类标本约2000种(占中国鱼类种数的2/3),近10万号,收藏有常见的淡水和海洋经济鱼类标本以及许多世上绝无仅有的鱼类新种模式标本:有中华鲟、白鲟等国家一级保护动物标本;有世界上最小的脊椎动物、国内仅有的2尾莱氏矮虾虎鱼(成鱼雌体体长不足10毫米)标本;有日本明仁天皇赠送的60余种产于日本的名贵虾虎鱼类标本和各国赠送的罕见鱼类标本.这是我国鱼类标本较为齐全、能为国内外鱼类学家研究中国鱼类提供标本和资料的少数标本室之一. 相似文献
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自 1 98 5年以来 ,大洋钻探科学考察船“JOIDES·决心者”号已经开始在海底大范围内钻孔取样、录井、安装长期观测仪器 ,以验证1 996年 ODP长期计划 ( L ong-Range Plan)中提出的最具紧迫性质的科学任务。作为地球科学领域最为成功的一项国际合作计划 ,尽管大洋钻探计划 ( Ocean Drilling Program )将在2 0 0 3年 9月 3 0日告一段落 ,但我们仍将有许多机会参加最后的 ODP科学考察工作 ,有兴趣的科学家可以通过网站 http://www-odp.tamu.edu得到更多的信息。美国海洋研究机构联合公司 ( Joint O-ceanographic Institutions,Inc.,JO… 相似文献