Acoustic measurements of zooplankton distributions in the sea     

Pieper  R. E.; Holliday  D. V. 《ICES Journal of Marine Science》1984,41(3):226-238

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The dependence of recruitment on parent stock derived from the average recruitment     

Cushing  D. H. 《ICES Journal of Marine Science》1984,41(3):276-279

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Design and performance analysis of a Digital Acoustic Telemetry System for the short range underwater channel   总被引：1，自引：0，他引：1  

Catipovic  J. Baggeroer  A. Von Der Heydt  K. Koelsch  D. 《Oceanic Engineering, IEEE Journal of》1984,9(4):242-252

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Fishing effort and fisheries policy     

S. Cunningham  D. Whitmarsh 《Marine Policy》1980,4(4):309-316

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A simulacrum of the Iceland cod stock     

Cushing  D. H. 《ICES Journal of Marine Science》1982,40(1):27-36

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Uptake of plutonium from seawater and sediment by a marine polychaete worm     

C. N. Murray  W. Renfro 《Journal of Oceanography》1976,32(6):249-252

The results of the uptake of plutonium 239 from sediment by a marine polychaete wormNereis diversicolor is reported in the present paper. A comparison is made of the relative importance of two possible uptake pathways, sediment and seawater by which this worm may obtain its plutonium body-burden. Under the laboratory conditions used for the comparison of those two routes it would appear thatNereis obtains greater than 98% of its body activity from seawater.  相似文献   

Evaporative weathering of petroleum residues: The age of pelagic tar     

James N. Butler 《Marine Chemistry》1975,3(1):9-21

The rate of evaporative weathering of a component of crude oil residue is assumed to be proportional to its equilibrium vapor pressure and to the amount remaining in the sample. This model is tested using literature data on normal paraffin profiles of crude oil weathered artificially and gas chromatographic data on crude oil residues weathered on rocky shores. Semiquantitative agreement over the time range from 1 to 400 days is demonstrated. Application of the model to gas chromatograms of pelagic tar lumps collected at Station S near Bermuda in 1972 implies that most of these lumps were formed by fragmentation of much larger and older masses, some within less than one day of the time they were collected. The weathering of pelagic tar thus involves a great deal more physical fragmentation than was previously supposed.  相似文献   

The Dependence of Recruitment on Parent Stock in Different Groups of Fishes   总被引：1，自引：0，他引：1  

Cushing  D. H. 《ICES Journal of Marine Science》1971,33(3):340-362

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A pockmark field in the Patras Gulf (Greece) and its activation during the 14/7/93 seismic event     

T. Hasiotis  G. Papatheodorou  N. Kastanos  G. Ferentinos 《Marine Geology》1996,130(3-4):333-344

During a recent oceanographical-geophysical survey carried out in the southeastern part of the Gulf of Patras in Western Greece for the construction of an outfall, an active pockmark field was found. The pockmark field was formed in soft layered Holocene silts. The pockmarks are associated with acoustic anomalies attributed to gas-charged sediments. The pockmarks vary in size and shape from 25 to 250 m in diameter and from 0.5 to 15 m in depth and are among the largest and deepest observed in the world.

On July 14th, 1993, during the survey, a major earthquake of magnitude 5.4 on the Richter scale occurred in the area. During the 24 hour period prior to the earthquake the bottom water temperature anomalously increased on three occasions, whilst for a few days after the earthquake it was noted that the majority of the pockmarks were venting gas bublles.

It is considered that the three abrupt sea-water temperature increases were probably the result of upward migrating high-temperature gas bubbles in the water column. It is further suggested that the earthquake was the triggering mechanism and that the gas expulsion was caused by the reduction in the pore volume in the sediments resulting from changes in the stress regime prior to the earthquake. Therefore, it can be suggested that in seismic areas adjacent to pockmark fields, earthquake prediction may be achieved by monitoring the water temperature and/or the rate of gas venting in the pockmark field.

Our analysis indicates that the pockmark field in the Patras Gulf has formed slowly during the Holocene by continuous gas venting, which is periodically being interrupted by short-duration events of enhanced gas seepage triggered by earthquakes.  相似文献   

Transverse vibrations of a rectangular cantilever plate with thickness varying in a discontinuous fashion     

R.E. Rossi  P.M. Belles  P.A.A. Laura  S. La Malfa  L. Ercoli  D. Pasqua 《Ocean Engineering》1996,23(3):271-276

A numerical solution is obtained for the title problem by means of the popular finite element method. An experimental investigation of the problem is also presented for plates of square planform. The agreement between theoretical and experimental values is very good in the case of the fundamental frequency, and reasonably good when the second and third normal modes of transverse vibration are considered. It is concluded that beneficial effects are obtained in the sense that one generates a lighter structural element with higher fundamental frequency of transverse vibration. Hence, dynamic stiffening is achieved.  相似文献