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1.
《Oceanologica Acta》1998,21(1):21-31
During the PROGEMA I cruise which took place on the south-western Pacific coast of Mexico (between 14° and 16° N, 92° and 96° W), 3.5 kHz echosounding profiles, surface samples and cores as well as hydrological and oxygen minimum measurements down to 2250 m water depth were made in the Gulf of Tehuantepec. Chemical, sedimentological, mineralogical, X-ray and BEM analyses of waters, core and surface samples provided new data which permit a better knowledge of the Gulf of Tehuantepec margin, where tectonic activity is due to an active subduction.On the shelf of the gulf, the distribution pattern of quaternary deposits is affected by a double tectonic forcing and by eustatic oscillations of the sea level. The first tectonic control is linked to the existence of north-south tectonic troughs in the Tehuantepec Isthmus, in which the atmospheric circulation between the Gulfs of Mexico and Tehuantepec is accelerated by the Venturi effect. The resulting winds, called “Tehuanos”, play an important role in the forcing of surface circulation in the Gulf of Tehuantepec, inducing a deviation of the general circulation and thus forcing the distribution pattern of terrigenous sediment supply according to two physiographically and mineralogically distinct provinces, inherited from the past tectonic evolution, which are separated by the Tehuantepec axis.
- •-|A southeastern province related to the Caribbean Plate and fed by: (1) the rivers draining the Chiapas Massif; and (2) the Costa-Rica Current driving tropical and subtropical waters from Central America.
- •-|A northwestern province part of the North American Plate and fed by: (1) the Rio Tehuantepec which drains the Sierra de Oaxaca; and (2) the Californian Current.
- •-|shallow banks where the products of a present-day phosphatogenesis are concentrated because they are swept by upwellings. The latter are reinforced because the banks are situated south of the wind corridor;
- •-|tectonic depressions acting as sediment traps;
- •-|numerous canyons cutting the slope along brittle accidents, driving weak turbidity currents but which play an important role in the forcing of upwelling currents. Antarctic diatoms are found which are conveyed by the deep circulation from the South-Eastern Pacific and provide evidence that Antarctic Cold Water masses (AABW) rise towards the shelf.
2.
This paper considers wave impacts on baffles, on baffles or decks adjacent to a vertical wall, and on porous seawalls and/or sea beds. For seawalls and vertical baffles, impacts can occur in steep waves, whilst a deck can be struck from below by a rising wave crest either in open sea or in a tank with standing waves (sloshing). A simple analytical model for the pressure impulse, P, due to a wave of idealized geometry and dynamics is developed and applied to the following geometries with impermeable surfaces:
- •horizontal wave impact onto a vertical wall with a deck at the waterline,
- •vertical wave impact under a deck in the same configuration (equivalent to vertical water impact of a horizontal plate),
- •horizontal wave impact onto a surface-piercing vertical baffle in open sea,
- •as for 3. but with the baffle in front of a wall,
- •as for 4. but with a deck extending from the vertical wall to the baffle,
- •bottom-mounted baffle in front of a wall with impact occurring on the wall.
3.
《Ocean & Coastal Management》2000,43(7):537-556
Guidelines for developing and implementing sustainability indicators for marine capture fisheries were drafted during a recent expert consultation jointly organised by Australia and FAO in Sydney (Australia). This paper provides an overview of the guidelines and illustrates their application with an Australian example. As a background to the guidelines, the concept of sustainable development (SD) for marine capture fisheries was discussed and an agreed set of definitions and usage of common terms developed. The guidelines then outline the five sequential steps that need to be addressed in developing a meaningful set of indicators in the context of a Sustainable Development Reference System (SDRS). The five steps are:
- 1.specifying the scope of the SDRS;
- 2.developing a framework to agree on components within the system;
- 3.specifying criteria, objectives, potential indicators and reference values;
- 4.choosing the set of indicators and reference values;
- 5.specifying the method of aggregation and visualisation.
4.
《Ocean Modelling》2011,36(4):277-303
We investigate the influence of bottom topography on the formation and trapping of long upwelling filaments using a 2-layer shallow water model on the f-plane. A wind forced along-shore current, associated with coastal upwelling along a vertical wall, encounters a promontory of finite width and length, perpendicular to the coast.In the lower layer, topographic eddies form, which are shown to drive the formation of a filament on the front. Indeed, as the upwelling current and front develop along the coast, the along shore flow crosses the promontory, re-arranging the potential vorticity structure and generating intense vortical structures: water columns with high potential vorticity initially localized upon the promontory are advected into the deep ocean, forming cyclonic eddies, while water columns from the deep ocean with low potential vorticity climb on the topography forming a trapped anticyclonic circulation. These topographic eddies interact with the upper layer upwelling front and form an elongated, trapped and narrow filament.Sensitivity tests are then carried out and it is shown that:
- •baroclinic instability of the front does not play a major role on the formation of long trapped filaments;
- •increasing the duration of the wind forcing increases the upwelling current and limits the offshore growth of the filament;
- •modifying the promontory characteristics (width, length, height and slopes) has strong impact on the filament evolution, sometimes leading to a multipolarisation of the potential vorticity anomaly structure which results in much more complicated patterns in the upper layer (numerous shorter and less coherent filaments). This shows that only specific promontory shapes can lead to the formation of well defined filaments;
- •adding bottom friction introduces a slight generation of potential vorticity in the bottom layer over the promontory, but does not significantly alter significantly the formation of the filament along the outcropped front in the present configuration;
- •modifying the stratification characteristics, in particular the density jump between the layers, has only a weak influence on the dynamics of topographic eddies and on filament formation;
- •the influence of capes is also modest in our simulations, showing that topography plays the major role in the formation of long and trapped upwelling filaments.
5.
《Marine and Petroleum Geology》1987,4(2):127-131
Drilling, workover, injection and production operations can all cause physical impairment of the sandface and formation immediately around a wellbore. Matrix acidizing treatments are aimed at removing this type of damage. To obtain maximum damage removal most operators use in general a hydrochloric acid preflush followed by a mud acid main flush. During most acidising treatments large amounts of acids, usually of the order of one hundred gallons per foot of formation, are pumped into the reservoir, where various interactions occur with the matrix constituents, for instance:
- 1.• Cementing material is dissolved and clays and fines are released from their setting.
- 2.• Clays and fines are dissolved and gradually reduced in size.
- 3.• Acid-released clays and fines can be dislodged and plug pore throats.
- 4.• The pH of the spending acid increases and secondary precipitates can be formed.
6.
This study aims to constrain the base of the hydrates stability field in structurally complexsites using the case of Woolsey Mound, a fault-controlled, transient, thermogenic hydrates system, in Mississippi Canyon Block 118, northern Gulf of Mexico. We have computed the base of the hydrates stability field integrating results from a recent heat-flow survey, designed to investigate geothermal anomalies along fault zones which exhibit different fluid flux regimes. An advanced “compositional” simulator was used to model hydrate formation and dissociation at Woolsey Mound and addresses the following hypotheses:
- 1.Migrating thermogenic fluids alter thermal conditions of the Hydrate Stability Zone (HSZ), so heat-flow reflects fault activity;
- 2.Gas hydrate formation and dissociation vary temporally at active faults, temporarily sealing conduits for migration of thermogenic fluids;
- 3.High salinity and inclusion of thermogenic gases with higher molecular weight than methane produce opposite effects on the depth to the bottom of the hydrate stability zone.
7.
8.
《Oceanologica Acta》1998,21(1):1-20
During the Equanaute survey (June 1992), fourteen submersible dives were performed between 4950 and 2250 m water depths across the southern slope of the Côte d'Ivoire-Ghana Marginal Ridge (CIGMR), in the eastern Equatorial Atlantic. The CIGMR, a high-standing topographic marginal ridge along the Côte d'Ivoire-Ghana transform margin, is believed to result from a complex structural evolution due to the specific wrench-related rifting between Western Equatorial Africa and Northeastern Brazil, in Early Cretaceous times. In this paper we report and discuss geological observations made during dives, and sample analyses to resolve the lithology, paleoenvironmental conditions, age and origin of the CIGMR. The data help in better characterizing the different sedimentary and tectonic regimes which successively prevailed during the CIGMR formation and assessing the thermal regime operative during the fabrication and subsequent evolution of the margin. The thick sedimentary pile exposed along the southern CIGMR slope is made up of a repetitive clastic sequence indicative of a deltaic-to-prodeltaic environment. This sedimentary pile, of Early Cretaceous age, has recorded different stages of the transform margin structural evolution.
- 1.(1)|Syn- to post-lithification deformations first record extensional deformations related to the rifting of the adjacent northern divergent margin segment (the Deep Ivorian Basin).
- 2.(2)|Wrench tectonics has, at a later stage, produced intense fracturing and participated in local folding, chiefly detected upslope. The integrated studies of geological samples and in situ observations obtained during the Equanaute survey support models for transform margin evolution proposed mainly from geophysical data.
9.
10.
《Marine Policy》1998,22(3):229-234
The 1972 United Nations Conference on the Human Environment (Stockholm, UN Conference, 1972) outlined a ‘masterplan’ linking environmental assessment, environmental management and supporting measures as basic and inseparable elements of environmental actions plans. It also indicated the advantages of a regional approach in contributing to the solution of global problems. The Regional Seas Programme of UNEP (United Nations Environment Programme) was subsequently initiated in 1974 (UN General Assembly, 1972). Development of UNEP’s Regional Seas Programme demonstrated that the basic concepts formulated at Stockholm can effectively foster regional cooperation among interested States, and may benefit from the support of the United Nations system as a whole.The present Regional Seas Programme includes fourteen regions, comprising over 140 coastal States. It was conceived as an action-oriented programme encompassing a comprehensive, trans-sectoral approach to marine and coastal areas and to environmental problems, considering not only the consequences, but also the causes of environmental degradation. Each Regional Seas Programme is based on the needs of the region concerned. The Regional Seas Programmes promote the parallel development of regional legal agreements, and of action-oriented programme activities, as embodied in the action plans. The overall strategy to be followed, as defined by UNEP’s Governing Council (UNEP, 1974) is:
- 1. Promotion of international and regional conventions, guidelines and actions for the control of marine pollution and the protection and management of aquatic resources.
- 2. Assessment of the state of marine pollution, pollution sources and trends, and of the impact of pollution on human health, marine ecosystems and amenities.
- 3. Coordination of efforts with regard to environmental aspects of the protection, development and management of marine and coastal resources.
- 4. Support for education and training efforts to facilitate the full participation of developing countries in the protection, development and management of marine and coastal resources.
11.
Deep currents measured by moored current meters over the shelf-slope off Cape Shiono-misaki, Kii Peninsula during the period from 28 April, 1981 to 4 May, 1982 are analyzed to determine characteristics of the deep current before and after the large meander of the Kuroshio formed. The observed deep currents show some different characteristics between the periods before and after the formation of the large meander of the Kuroshio,i.e.:
- The mean current direction over the shelf slope changed to westward after the meander was formed, though it was eastward at two offshore stations before the meander was formed.
- The eddy kinetic energy, \(ke((\overline {u'^2 } + \overline {\upsilon '^2 } )/2)\) became large at all stations after the meander formed.
- It appears that there were current variations in the period band shorter than 10 days which propagated offshore before the meander formed but inshore after the meander formed.
- After the meander formed, the current variations with a period of O(25 days) were amplified at two of the three stations. The current variations in this period band showed high coherence among the three stations.
12.
The yearly variations of mean sea levels at various locations along the coasts of Japan have been investigated, based upon the data of observation taken at 55 tide-gauge stations from 1953 to 1970, and some discussions have been made on the relationships between those variations and meteorological and oceanographical conditions, etc. The results obtained are as follows:
- In cases covering 90% of all the tide-gauge stations, the magnitude of the annual mean rate of variation of ground level is less than 10 mm/year, and the mean value of the magnitude for all the stations is ?3.17 mm/year, while that exclusive of Osaka is ?1.7 mm/year.
- The effect of atmospheric pressure variation on the height of annual mean sea level is of the order of several centimeters in view from both time and place.
- In view of the characteristic types of variations, the coasts of Japan may be divided into five regions of similar mean sea level deviations. And in the yearly variations of mean sea levels, there can be seen a kind of variation which corresponds to the variation of oceanographical conditions such as abnormal fall of seawater temperature.
- The mean sea level deviations at various locations along the coasts of Japan, referred to the standard sea level “T.P.” are different for different places. Namely, (1) on the coast of the Japan Sea, the west coast of Kyushu, the coast of Sanriku and the coast of Hokkaido, the mean sea level is higher than on the Pacific coasts from Southern Kyushu to Southern Honshu. (2) Along the coast of the Seto-Inland Sea, the mean sea level is generally higher.
13.
《Marine environmental research》1987,22(2):123-149
- 1.1. The accumulation of aromatic hydrocarbons (AHs) and polychlorinated biphenyls (PCBs) kv English sole (Parophrys vetulus) exposed for up to 108 days to an urban (test) sediment was compared to that for English sole exposed to sediment from a reference area. The concentrations of identified AHs and PCBs in the test sediment were 32 μg/g dry weight and 2·2 μg/g dry weight, respectively. English sole exposed to test and reference sediments for 108 days had biliary concentrations of aromatic compounds fluorescing at BaP wavelengths of 0·6 μg/g, wet weight and hepatic concentrations of PCBs of 1·4 ± 0·6 μg/g wet weight which were ten and eight times, respectively, as great as those in reference sole. These results show that accumulation of AHs and PCBs from sediment by English sole is a significant route of uptake in contaminated environments.
- 2.2. 3H-benzo(a)pyrene (BaP) and 14C-PCBs were added to the test sediment to compare the uptake and metabolism of BaP to that of PCBs by sole. Steady-state concentrations of 3H-BaP and 14C-PCBs in tissues and fluids were reached by 4 days and 14 days, respectively. At steady state, the level of covalent binding of 3H-BaP to hepatic proteins in test sole was six times greater than that of 14C-PCBs, and there was significantly greater relative formation of BaP-glutathione (GSH) conjugates than PCB-GSH conjugates. Thus, the amount of BaP metabolized to reactive metabolites was greater than that for PCBs, even though the concentration of 14C-PCBs in liver of test sole was five times as great as that of 3H-BaP.
- 3.3. Trace amounts of 3H-BaP were also added to the reference sediment to determine how simultaneous exposure of English sole to those contaminants already present in the test sediment affected the metabolism and disposition of BaP. The 3H-BaP concentration ratios for liver to sediment and bile to sediment, as well as proportions of biliary BaP-GSH conjugates in test sole, were significantly greater than in reference sole. Thus, the formation and accumulation of potentially toxic metabolites of a carcinogenic AH (BaP) in sole liver were increased by simultaneous exposure to contaminants present in an urban sediment.
14.
The distribution of pelagic blue-green algae, especially ofTrichodesmium thiebautii, was investigated on the basis of the collection of theHakuhō Maru Cruise KH-69-4 along 155°W (50°N-15°S) in the North Pacific Ocean from September to November 1969.
- Five species were identified:Trichodesmium thiebautii (most predominant),T. erythraeum, Oscillatoria sp.,Katagnymene spiralis andRichelia intracellularis.
- T. thiebautii was most abundant in the western North Pacific central water and abundant next to it in the equatorial water, but it did not occur in the subarctic water.
- T. thiebautii was ubiquitously distributed in the lower layer of 100–200 m in the equatorial water, though not in a large quantity.
- T. thiebautii inhabited only the water warmer than 20°C. In its main habitat, nitrate and nitrite were almost zero, but ammonia and phosphate were present. There was not found any correlation between its occurrence and the salinity.
- Blue-green algae were generally thinly populated in the water rich in diatoms.
15.
Akira Kurata 《Journal of Oceanography》1970,26(2):81-86
Transudation of vitamin B12 from the surface layer of bottom muds in Maizuru Bay and in the Sea of Hiuchi was investigated in this report. The total counts of heterotrophs and bacteria producing vitamin B12 in the bottom muds in these coastal regions were also examined. Results obtained were as follows:
- In the marine bottom in these coastal regions, vitamin B12 is continuously transuded from the surface layer of bottom muds to sea water. Accordingly, it is reasonably supposed that the surface layer of bottom muds, in which vitamin B12 is produced and accumulated, is a source of provision of the vitamin in the coastal regions.
- On an average, the quantity of transudation of vitamin B12 from the surface layer of bottom muds to sea water is 2.6 μμg/cm2/hr and 5.2μμg/cm2/hr in Maizuru Bay and in the Sea of Hiuchi respectively.
- In the surface layer of bottom muds in these coastal regions, the quantity of transudation of vitamin B12 is correlated with the content of the vitamin and the counts of bacteria producing the vitamin.
16.
Tomotoshi Okaichi 《Journal of Oceanography》1983,39(5):267-278
The cause of red tides appearing in neritic waters in Japan have been discussed by several workers in relation to the development of eutrophication. The author has been engaged in marine environmental studies on outbreaks of red tides, mainly, in the Seto Inland Sea since 1964 using a combination of the following approaches:
- surveys of the red tides that have occurred,
- elucidation of the oceanographical and biological characters of the water areas where red tides occur,
- isolation of the red tide organisms for physiological studies of their growth,
- chemical and biological assays of the growth promoting factors, and
- estimation of the effects of pollutants on the growth of the red tide organisms.
17.
Abyssal currents along the northern periphery of the Shikoku Basin south of Japan were measured by current meters moored off Cape Daio-zaki, Cape Shiono-misaki and Cape Ashizuri-misaki and on the eastern foot of the northernmost part of the Kyushu-Palau Ridge. Total length of observation off Cape Shiono-misaki was about five years including the periods of the Kuroshio large meander and no meander. Analyses of current data show:
- Mean currents with a magnitude of 5–10 cm sec?1 were observed during the whole observation period at all of current meters which were set 400 m above the sea bottom that was deeper than 4,500 m. The mean current for each current meter was parallel to the local bottom contour arond each station and was toward a direction looking the Nankai Trough (a trough located along the northern end of the Shikoku Basin) to the left.
- At each station located above the shelf toe off Cape Daio-zaki and off Cape Shiono-misaki and on the foot of the Kyushu-Palau Ridge, the mean current increases with depth (a bottomward intensification of the mean current), and the vertical extent of the mean current is estimated to be about 2,000 m above the sea bottom.
- At a station located at 2,600 m depth on the continental slope off Cape Shiono-misaki, no bottom-ward intensification of currents was observed.
18.
The distribution of inorganic nitrogen compounds and the metabolic rates of these compounds by microorganisms as a whole were investigated in the Seas of Hiuchi and Bingo. The results obtained are as follows:
- Of inorganic nitrogen compounds, the contents in sea water, those in bottom muds, the uptake or liberation rates of microorganisms as a whole in sea water, and the liberation rates from bottom muds to sea water are 0.2～4.0 μg at. N/l, 3～60 μg at.N/100 g, 0.01～0.5 μg at.N//lhr, and 0.3～1.9 μg at.N/100 cm2/hr, respectively, and these contents or rates of ammonia usually are the largest of these inorganic nitrogen compounds.
- From the above-mentioned results and the others, it is suggested that the nitrogen in the seas circulates mainly in sea water itself and the course of nitrogen cycle, which passes through bottom muds, is not so important, and further that, of the cycle of inorganic nitrogen compounds, the main course is the course which ammonia is liberated from organic nitrogen compounds and it is immediately uptaked by microorganisms, and the course which it is oxidized to nitrate and the others are not so important.
19.
《Marine Policy》1999,23(1):11-24
By 1 August 1998 Regulation I/7 of the 1995 amendments to the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (1978) requires a comprehensive submission of information to the International Maritime Organization supporting an Administration’s claim that it complies fully with, or is in the process of implementing, STCW ’95 via policy and legislative processes. Once the complete information is received by the International Maritime Organization, the Secretary-General must submit a report to this effect to the Maritime Safety Committee. Three questions emerging from this controversial provision in STCW ’95 are:
- •When, if ever, is the information from an Administration complete?
- •What is the time frame allocated for confirmation by the IMO Secretariat?
- •How does IMO assess whether the claim by an Administration is valid?
20.
Shinsuke Tanabe 《Journal of Oceanography》1985,41(5):358-370
I am extremely grateful and honored for being awarded the Okada Prize (1985) for my study. The present article reviews my research on the distribution, behavior and fate of PCBs in the marine environment. The outline of this study is summarized as follows:
- Polychlorinated biphenyls (PCBs) were detectable in the wide range of environmental media and biota of the Seto-Inland Sea, Japan, in which much high concentrations were found in sediment and biological samples due to their hydrophobic, lipophilic and less biodegradable properties as well as their extensive production and use in estuarine and coastal regions.
- PCBs extend the boundaries of their distribution all over the global environment, being evidenced by their occurrence in open ocean atmosphere, hydrosphere and biosphere, even in Antarctica. The global contamination of PCBs is much more prominent in northern hemisphere than in southern hemisphere.
- The sinking rate of PCBs from surface to deeper layers in open ocean water column is relatively slower in tropical waters than in high latitude ones. This implies the possible prolonged contamination of persistent synthetic organic chemicals in the tropical marine environment.
- The bioaccumulation processes in marine ecosystems can be explained by the physicochemical and biochemical properties of PCBs and the metabolic capacity of organisms. In higher animals, additional factors such as parturition and lactation are also related to this process.
- Total PCB load in global environment was estimated to be about 370 thousand tons. Of this, most amounts were in coastal sediment and open ocean water. Presently, about 780 thousand tons of PCBs are still in use mainly in electrical equipments. In order to reduce the PCB levels in marine environment, pertinent measures to prevent the further discharge and safe disposal of PCBs are required.