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71.
崂山花岗岩地区含锶、偏硅酸矿泉水的形成机理 总被引:1,自引:0,他引:1
报道了崂山花岗岩地区矿泉水的特征。指出其矿泉类型为含锶、偏硅酸型,并讨论了其形成机理。 相似文献
72.
使用切向流超滤系统得到粒度较均匀的Fe(OH)3胶体,进而对Fe(OH)3胶体粒子与Cu2 的作用进行了研究,并将实验结果与南沙群岛海区表层水中铜与胶体物质结合状况的调查数据进行了比较分析,得到如下结果:(1)在海水介质中,铜在Fe(OH)3胶体上结合的百分率(pH>5)随pH的升高而下降,随着Fe(OH)3胶体浓度的减小而下降?(2)在天然海水介质中,使铜在Fe(OH)3胶体上结合的百分率在50%-70%的有机物浓度为1.0mg·L-1,有机物浓度的增大使铜与无机胶体结合的百分率有下降的趋势? 相似文献
73.
A bottom longline fishery operated in the EEZ of New Caledonia from 1988 to 1991. Fishing focused on five seamounts with summits at depths ranging from 500 to 750 m. The target species was alfonsino, Beryx splendens. As the soundings available from marine charts were not detailed enough, the fishing masters had to make their own charts in order to set the gear in the right location. A series of 11 scientific cruises devoted to a research program on alfonsino was launched in late 1991. During the first scientific cruises, several days were spent mapping the seabed to improve the existing knowledge of the topography of three seamounts by coupling the EDO echosounder depth measurements to the GPS positions. As this procedure is slow, it is applicable to limited areas or, if a wider grid is used, to large zones to locate major structures such as ridges and seamounts. The emergence of the multibeam echosounder has greatly improved seabed mapping performance. This tool seems to fit the requirement of exploratory deep-bottom fishing particularly well, as it covers large areas while providing details of the bottom. The EM 12 was used to obtain bathymetry and imagery of the SE portion of the EEZ of New Caledonia, covering an approximate area of 70,000 km2 in two weeks. For depths ranging from 500 to 4,500 m, the results were impressive. They confirmed the known major features and provided greater topographical detail, revealing fine unknown structures. They also provided information on the type of substratum, information which might influence the fishing strategy. Finally, they made it possible to obtain an accurate estimate of the exploitable area which in turn led to new stock estimates. 相似文献
74.
Michael Riedel 《Marine Geophysical Researches》2007,28(4):355-371
Two single-channel seismic (SCS) data sets collected in 2000 and 2005 were used for a four-dimensional (4D) time-lapse analysis
of an active cold vent (Bullseye Vent). The data set acquired in 2000 serves as a reference in the applied processing sequence.
The 4D processing sequence utilizes time- and phase-matching, gain adjustments and shaping filters to transform the 2005 data
set so that it is most comparable to the conditions under which the 2000 data were acquired. The cold vent is characterized
by seismic blanking, which is a result of the presence of gas hydrate in the subsurface either within coarser-grained turbidite
sands or in fractures, as well as free gas trapped in these fracture systems. The area of blanking was defined using the seismic
attributes instantaneous amplitude and similarity. Several areas were identified where blanking was reduced in 2005 relative
to 2000. But most of the centre of Bullseye Vent and the area around it were seen to be characterized by intensified blanking
in 2005. Tracing these areas of intensified blanking through the three-dimensional (3D) seismic volume defined several apparent
new flow pathways that were not seen in the 2000 data, which are interpreted as newly generated fractures/faults for upward
fluid migration. Intensified blanking is interpreted as a result of new formation of gas hydrate in the subsurface along new
fracture pathways. Areas with reduced blanking may be zones where formerly plugged fractures that had trapped some free gas
may have been opened and free gas was liberated. 相似文献
75.
This paper presents a numerical model study of the propagation of water waves using the parabolic approximation of the mild-slope equation in the orthogonal coordinate system. Two types of coordinate systems are studied: (a) a general form of orthogonal coordinate system and (b) the conformal system, a special form of orthogonal coordinate system. Two typical examples, namely, expanded breakwaters and a circular channel, are studied to validate the model. First, the examples are studied by use of the general orthogonal coordinates. Then the same examples are computed by use of the confonnal system. The computational results show that the confonnal coordinate system generally gives better predictions than the general orthogonal system. A numerical technique for generating the conformal grid is combined with the numerical model to improve the practicability of the model. The comparison between the result from the numerical grid system and that from the analytical grid system shows that reliable computational results can be obtained by use of the numerical confonnal grid system. 相似文献
76.
20世纪末,地震勘探技术在油气勘探、煤田勘探、工程勘探等多方面的应用都有了突飞猛进的发展。总结了近年来地震勘探在岩性、沉积相、构造体系等不同地质条件下的应用实例,用以说明地震勘探的多用性及其强大的生命力。 相似文献
77.
The vegetation communities and spatial patterns on the Fire Island National Seashore are dynamic as the result of interactions with driving forces such as sand deposition, storm-driven over wash, salt spray, surface water, as well as with human disturbances. We used high spatial resolution QuickBird-2 satellite remote sensing data to map both terrestrial and submerged aquatic vegetation communities of the National Seashore. We adopted a stratified classification and unsupervised classification approach for mapping terrestrial vegetation types. Our classification scheme included detailed terrestrial vegetation types identified by previous vegetation mapping efforts of the National Park Service and three generalized categories of high-density seagrass, low-density seagrass coverages, and unvegetated bottom to map the submerged aquatic vegetation habitats. We used underwater videography, GPS-guided field reference photography, and bathymetric data to support remote sensing image classification and information extraction. This study achieved approximately 82% and 75% overall classification accuracy for the terrestrial and submnerged aquatic vegetations, respectively, and provided an updated vegetation inventory and change analysis for the Northeast Coastal and Barrier Network of the National Park Service. 相似文献
78.
J. Acosta E. Uchupi A. Muñoz P. Herranz C. Palomo M. Ballesteros 《Marine Geophysical Researches》2003,24(1-2):1-40
In this paper we discuss the results of a swath bathymetric investigation of the Canary archipelago offshore area. These new
data indicate that volcanism is pervasive throughout the seafloor in the region, much more that would be suggested by the
islands. We have mapped tens of volcanic edifices between Fuerteventura and Gran Canaria and offshore Tenerife, La Gomera,
El Hierro and La Palma. Volcanic flows are present between Tenerife and La Gomera and salic necks dominate the eastern insular
slope of La Gomera. This bathymetry also supports land geologic studies that indicate that the oceanic archipelago has acquired
its present morphology in part by mass wasting, a consequence of the collapse of the volcanic edifices. In the younger islands,
Tenerife, La Palma and El Hierro, the Quaternary (1.2 to 0.15 Ma) debris avalanches are readily recognizable and can be traced
offshore for distances measured in tens of km. Off the older islands, Lanzarote, Fuerteventura, Gran Canaria and La Gomera
(<20 to 3.5 Ma), the avalanches have been obscured by subsequent turbidity current deposition and erosion as well as hemipelagic
processes. The failure offshore western Lanzarote is in the form of a ramp at the base of the insular slope bound on the seaward
side by a scarp. Its size and the lack of evidence of rotation along its landwards side precludes the possibility that it
is a slump. It probably represents a slide whose outer scarp is caused by break-up of the slide. Mounds on the ramp’s surface
may represent post-displacement volcanic structures or exotic blocks transported to their present locations by the slide.
The failures offshore Fuerteventura are so large that, although they occurred in the Miocene-Pliocene, exotic blocks displaced
from upslope are still recognizable in the insular margin morphology. The Canary Island insular margin appears to be a creation
of Miocene-Pliocene mass wasting and more recent turbidity current deposition and erosion, and hemilepagic deposition. Failures
offshore La Gomera are due to debris flows and/or turbidity currents. These events have obscured earlier mass wasting events.
An erratum to this article is available at . 相似文献
79.
80.
无机碳与雨生红球藻(Haematococcus pluvialis)细胞调节物质 总被引:4,自引:0,他引:4
以单细胞雨生红球藻为材料,采用酸碱滴定和CO2加富通气培养微藻的方法,对旧液中HCO3^-和CO3^2-浓度变化以及对红球藻细胞生长的影响进行了研究。结果表明,旧液具有限制红球藻细胞生长和诱导细胞转化的作用。同时,旧液中无机碳离子浓度明显高于新液。培养液中富含CO3^2-时,各细胞数量与CO3^2-浓度呈正相关,相关系数为0.88。溶液中仅有HCO3^-时,各细胞数与HCO3^-浓度也呈正相关性。因此,排除了CO3^2-和HCO3^-作为旧液中的调节物质,限制红球藻细胞生长和诱导细胞转化的可能性。旧液乙酸乙酯提取物生物检测实验表明,在粗提取物中有降低细胞增长和诱导细胞转化的活性,表明调节物质能溶于有机相,也反过来证实无机碳离子不是旧液中的调节物质。DNA含量和倍性分析结果表明,红球藻游动细胞DNA复制可以加倍后不经过原生质分裂就可以再次进行,因此推测旧液中的调节物质对原生质分裂过程产生抑制作用,而不对DNA复制过程产生抑制作用。 相似文献