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1.
We analyze the data of investigation of the intrusive structure of the Gulf-Stream frontal zone obtained in making frequent drift sections with the help of an MGI-8102 probing complex, study the regularities of variation of temperature, salinity, and density along separate intrusions, and present a series of results connected with the specific features of initiation and development of intrusions and the types of exchange processes determining their transformations. It is shown that the T-diagrams of all intrusions are well separated into segments with different slopes. Moreover, by comparing the slopes and locations of these segments with each other and with the T-diagrams of the Gulf Stream and slope waters, we can fairly reliably attribute the corresponding segments of intrusions to one of the following four types: initial dynamic folds of the frontal zone, layers of domestic water separating the intrusive segments of foreign water from each other, intrusive segments characterized by the penetration of ambient water, and segments not intrusive initially but getting the required slope as a result of interaction with upper and lower intrusive segments. For segments of the last two types, it is possible to specify the predominant type of exchange.  相似文献   

2.
The heat lability of succinic dehydrogenase, malic dehydrogenase and lactate dehydrogenase in cell-free extracts ofVibrio marinus MP-1 grown at 15C was compared for the tris buffer suspended enzymes and the NaCl suspended enzymes. The tris buffer suspended enzymes lost 50 percent activity at low thermal exposure between 5C and 27C. No activity was evident on thermal exposure between 32C and 39C. The enzyme extracts suspended in NaCl at 36 % were more heat stable, losing 50 percent activity after exposure between 16C and 40C. The enzymes lost all activity on thermal exposure between 33C and 42C in the presence of NaCl.  相似文献   

3.
Siome, which was firstly defined by Uda (1938); is a line of convergence on the sea surface. There are many kinds of siome in the sea. I propose in this paper that siome should be classified into streak and front. Streak is defined as the convergence within the same water mass and front the convergence between two different water masses. Streaks and fronts are classified into more details on the basis of their mechanisms of generation. The proposed classification will be useful for understanding the dynamics of siome and should help to promote interdisciplinary studies around siome regions.  相似文献   

4.
The vertical distribution of benthic organisms in the sediment profile was studied using horizontally sliced sediments collected at five stations at depths from 115 to 472 m in Suruga Bay, central Japan. Using sieves of 1.0 and 0.5 mm mesh, benthic organisms were divided into two size classes, smaller macrobenthos (>1mm, <1g wet weight) and larger meiobenthos (1.0 mm0.5 mm). The maximum depth of vertical distribution of organisms in the sediment profile was expressed by the 95 % intercept of the cumulative % curve of the number of individuals drawn with respect to depth in the sediment. It has long been supposed that benthic animals are concentrated in the surface centimeters of sediment in the deep-sea system, and the present study clearly substantiated this. Most benthic organisms of both of these two size classes were concentrated in the upper 5 cm of sediment. The vertical distribution was almost always deeper in the case of smaller macrobenthos than for larger meiobenthos. However the difference could not be substantiated statistically since the number of samples was insufficient. The maximum depth indices of polychaetes were found to be significantly larger than those of crustaceans in the case of macrobenthos, while in the case of meiobenthos, the difference was not significant. The maximum depth index of all benthic organisms was positively and significantly correlated with water-depth and the possible cause for this relationship is discussed.  相似文献   

5.
The relationship between Cd and PO4 in the Kuroshio and Oyashio regions and the Okhotsk Sea was examined. The resultant equations are as follows: Cd (ng l–1)=37.0 PO4 (M)+2.6; Cd(ng l–1)=32.1 PO4 (M)+1.2 and Cd (ng l–1)=34.1 PO4 (M)+7.9, respectively. These results are in good agreement with previously reported studies, and indicate that during removal from surface waters to deeper waters by biological assimilation and regeneration in deeper waters Cd and PO4 maintain the same ratio in the open ocean. The relationship between Cd and PO4 in coastal waters, however, differed from that in the open ocean.  相似文献   

6.
Over 20 occurrences of discontinuous limestone blocks, locally called calcari aLucina, were mapped in the Tuscan—Romagna region of the northern Italian Apennines. The limestones, consisting of a variable mixture of authigenic carbonates (calcite, dolomite, and aragonite), sulfides (primarily pyrite), and allogenic silicates, occur in association with turbidite and hemipelagite units that were deposited in foredeep basins during early to late Miocene times. The limestone blocks are interpreted to represent relicts of carbonate buildups formed around methane-rich fluid vents on the basis of their (1) striking petrographic similarities to carbonates from cold vents in the modern oceans; (2) unique chemosynthetic-like fauna, and (3) anomalously negative 13C values ( 13C = – 16 to – 58 PDB). The contemporaneous tectonism of the Apennine orogeny is likely to be the primary cause for the expulsion of the methane-rich fluids to the seabed in a manner analogous to the fluid-flow processes occurring at modern accretionary prisms.  相似文献   

7.
The detailed oceanic structure was observed near the shoal Kokusho-sone (3000N, 12830E), which is located near the axis of the Kuroshio in the East China Sea. The detailed temperature cross-sections along the meridian 12830E, which passes over the shoal, strongly suggest that upwelling is forced along the north slope of the shoal. The behavior of the coastal waters near the Kuroshio front and of the cold water belt along the north-western side of the Kuroshio are also discussed.  相似文献   

8.
In an analysis of video observations of gravel transport in the West Slent, UK, collective and individual characteristics of 458 bursts of bedload have been examined and the transport velocity and distance of 1680 individual particles in a consecutive succession of burst events determined. Infrequent, long duration, high stress events account for 60% of total transport in only 24% of the total time with the mean free path and transport velocity for particles being 0.16 m and 0.22 m/s, respectively. Clear links between intense intermittent turbulence and bedload transport revealed in this study, suggest progress in modelling requires a clearer understanding of near bed flow structure.  相似文献   

9.
The reflection and breaking of internal waves on a sloping beach were studied in a small wavetank filled with water and petroleum. The dependence of the reflection coefficient of the internal waves on wave steepness and on beach slope is found to be very similar to that of surface waves. The reflection coefficient is small for the very gentle slope, increases rapidly as the slope increases, and becomes almost constant for the steep slope. The reflection coefficient decreases with increase of the wave steepness. Also, the transition slope at which the coefficient curve has the maximum gradient increases with increase of the wave steepness. Breaking pattern of the internal waves is classified into four types; breaking, semi-breaking, wrinkle-generating, and non-breaking. Their dependence on beach slope and wave steepness is examined. The regular sequence of the four breaking types from breaking to non-breaking is observed with decrease of wave steepness or with increase of beach slope.  相似文献   

10.
The values of the function (T, S) on theT, S straight lines with different angular coefficients have been analysed. It is shown that at the point of contact of theT, S straight lines with the corresponding isopycnals, has a conventional maximum and the density ratio isR=1. It is inferred that a conventional density maximum may occur and that theT, S gradients are compensated at the oceanic fronts separating the sub-arctic and subtropical water structures.Translated by Vladimir A. Puchkin.  相似文献   

11.
Ishiwatari  R.  Hirakawa  Y.  Uzaki  M.  Yamada  K.  Yada  T. 《Journal of Oceanography》1994,50(2):179-195
Organic geochemical study of bulk organic matter (OM), hopanoid hydrocarbon and normal hydrocarbon (C23C35) was conducted for a 936-cm-long sediment core sample from the Oki Ridge of the Japan Sea (Core KH-79-3, C-3; 37°03.5 N, 134°42.6E, water depth 935 m). Stable carbon isotopic ratios were also measured for both bulk OM and individual hydrocarbons. The following results were obtained: (1) The weight ratios of total organic carbon to total nitrogen range from 6.2 to 9.4 in the core. The 13C values of bulk OM range from –25.1–20.7%.. The 13C values of OM in the sections of 140190 cm are lower (–25–24) than those in the other sections (–23–21). This result indicates that OM in the core except for the 140190 cm sections is essentially of marine origin. (2) The 13C value of diploptene (a hopanoid hydrocarbon) in the last glacial maximum (LGM), is –66.3 (vs. PDB), which indicates it originating in methanotrophic bacteria. This result provides evidence to support for the previous ideas (Oba et al., 1980, 1984; Masuzawa and Kitano, 1984) that the bottom waters in the Japan Sea were anoxic in LGM. (3) Long chain (C23C35) n-alkanes of higher-plant wax origin were found throughout the core. Their concentration is high in 140190 cm in depth, suggesting that eolian dust load was high in LGM. (4) The n-alkane/TOC ratio increases with decreasing 13C values of bulk OM. This result indicates that the load of terrestrial (probably eolian dust-derived) OM to the Japan Sea became higher in colder climates. (5) The CPI values of long-chain n-alkanes are different in different 13O stages of paleoclimate, probably reflecting variations in species of terrestrial higher plants as a result of climatological adaptations.  相似文献   

12.
The activity of photosynthesis and the contents of chlorophylla and pheo-pigments were compared in the samples of the intake and effluent seawater of Owase-Mita Thermal Power Plant and in the seawater samples in the Yoshimi Bay before and after heat treatment. At Owase-Mita Thermal Power Plant, after passage of sea water through the cooling system chlorophylla content reduced to about a half and pheo-pigment content doubled in August with high temperature (25–27C), but the contents of chlorophylla and pheo-pigments changed little in January with low temperature (16C); whereas the depression of photosynthetic activity after passing through the cooling system was 71–77 % in August and 31–46 % in January. In the laboratory experiments, the heat treatment at 34–43C for 7–8 sec., which resulted in temperature rise of 7–8C, gave the decrease of chlorophylla and an increase of pheo-pigments in August temperature (26.5C), but a slight decrease of chlorophylla and a slight increase of pheo-pigments in November at the initial temperature of 19.2C, while in January and December the samples with low initial temperature (11.6 and 10.8C) showed almost no change in the content of pigments; the decrease in photosynthetic activity was 32 % in August sample,ca. 11 % in November sample,ca. 15% in January and almost no change in December. It is concluded that the photosynthetic carbon assimilation of marine phytoplankton is suppressed by passing through the cooling system of a thermal power plant even at lower water temperature in winter, while the content of chlorophylla is affected very little at a temperature below 20C.  相似文献   

13.
Analysis is made of wind and wave data, which were obtained during the passage of Typhoon 8013 at an Ocean Data Buoy Station south of Honshu operated by the Japan Meteorological Agency, in order to investigate the wave dependence of sea-surface roughness parameter in the situation where wind waves are dominant with less significant swells. The data fit better the wave-dependent expression of the wind stress,z 0 p/u*=, than to Charnock's formula,gz 0/u*2=, wherez 0 is the roughness length, p the angular frequency of the spectral peak of wind waves,u* the friction velocity of air,g the acceleration of gravity, and are non-dimensional constants. The results are very similar to those of our previous study using data from an oil producing platform in the Bass Strait, Australia, although the type of observation system and the synoptic situation of the winds and wind waves were totally different.  相似文献   

14.
Temperature and currents were measured 100 m south of the Pipe Organ vent site on the Juan de Fuca Ridge during a 5-day interval in September 1997 to examine the temporal variability of hydrothermal heat signals close to a source. Temperatures were sampled at three depths every 15 s while current speed and direction were sampled at a single depth hourly. Results show that rapid potential temperature () changes of as much as 0.02°C occurred at all three depths, partly caused by changes in current speed and direction. Spectra of showed no prominent spectral peaks, however. An analytic model of heat transport under variable currents was used to help put observed temporal variability into context and to point out problems with estimating hydrothermal heat fluxes from mooring data. Model distributions, when contoured on a horizontal plane and animated, demonstrate the pooling of effluent over vents at various times, the streaming of effluent as a very narrow plume away from vents at times of large current speed, and the spawning of boluses of heated fluid and their transport away from venting regions when a pooling period is followed by a streaming period. Model results also show that estimated heat flux based on mooring data is strongly dependent on analysis assumptions and suggest that vents are capable of causing measurable anomalies as far as several kilometers downstream.  相似文献   

15.
On the basis of the generalization of the concept of standard ocean to the Black Sea, we deduce practical formulas for the conversion of pressure into depth and vice versa depending on the latitude of the place with regard for the equation of state for 1980. The error of these relations for the standard Black Sea (whose salinity is equal to 22.2 at a temperature of +9°C from the surface to the bottom) does not exceed ±0.2m and ±0.2dbar. The difference between the practical and actual depths in winter and summer periods does not exceed ±0.35m for depths varying within range 0–2000m. The proposed practical formulas enable one to simplify the procedure of rapid evaluation of depth (or pressure) in real time by excluding the procedure of integration over a specific volume.  相似文献   

16.
The heat balance of the upper ocean under a land and sea breeze was investigated based on observations of sea water temperature in the upper 300 m layer and heat flux across the sea surface at a fixed station in Sagami Bay (3510N, 13925E) during two periods of two days in August 1980 and three days in August 1981. During both periods, a typical land and sea breeze of 4–6 m sec–1 at maximum prevailed in the observation area. Large diurnal variation of sea surface temperature with a maximum peak around noon LST was observed during both periods (the daily value of the range was 0.9C and 2.5C in 1980, and 1.2C, 1.5C and 1.7C in 1981). It was found that these large temperature variations were caused by diurnal variation of the wind speed which dropped to 0–3 m sec–1 at noon when the strongest insolation (–270 Wm–2) penetrated the sea and at midnight in association with alternations of the land breeze and the sea breeze. On the other hand, vertical mixing of the sea water caused by the wind stress and/or convection due to cooling at night extended down only to the surface 10 m layer. Horizontal heat advection was negligibly small. Therefore the local time change of the heat content in the upper 10 m water column was affected mainly by the heat flux across the air-sea interface which was estimated from data on radiation fluxes measured directly on board and latent and sensible heat fluxes calculated by the aerodynamic bulk method. The water temperature below the 10 m layer also varied with time and the temperature variation in the thermocline (20–50 m depth) was frequently larger than that of the sea surface temperature. However, the variation in the upper 10 m layer was little influenced by that below the layer.  相似文献   

17.
Salinity, preformed phosphate and AOU distribution on the sigma-t surfaces of 26.8 and 27.3 of the central North Pacific Ocean, as well as the topography of these density surfaces, were studied. The direction of water flow suggested by the AOU distribution on these density surfaces was compared to that indicated by the acceleration potential contours on the t =125 cl/ton and t =80cl/ton surfaces drawn by Joseph L.Reid, Jr. The disagreements were explained in terms of mixing and possible gradients of primary production at the sea surface. On the 26.8 sigma-t surface a southward flow connecting the westward flow south of the Aleutian chain and the eastward flow farther south, between 175E and 180 is suggested by the AOU distribution but is not implied by the acceleration potential contours. If the circulation pattern at this density surface is similar to that at the sea surface, this southward flow is very likely to be real.  相似文献   

18.
Diatomaceous silica, pretreated at various temperatures between 125 and 900C, was subjected to dissolution experiments and was analyzed using X-ray diffraction and infrared spectra. The diatomaceous silica preheated up to 900C, dissolved throughly into the solution of 2 per cent Na2CO3. On the digestion in the solution of 2 per cent Na2SO4, the dissolution of the silica decreased as the pretreating temperature increase; the degree of dissolution was different for various species. According to infrared absorption studies, the diatomaceous silica pretreated at a temperature below 500C preserved the reversibility of dehydration-rehydration almost qualitatively, while heating above 500C the samples lost the reversibility. Deformation of some kinks of diatomaceous silica pretreated above 500C, was percepted on infrared absorption spectra around 1,150 cm–1. The samples pretreated up to 900 C, however, did not show such an internal structural change as could be identified by the X-ray diffraction analysis. The content of Al and Fe in diatomaceous silica was low and have not much difference in quality among diatom species. From these experimental results, it was adequately understandable that diatomaceous silica, which has a metastable character, is variable in the silica forms among species and its process and rate of transformation of internal structure and/or surface sites by the treatment at given temperatures also show differences.  相似文献   

19.
Dependences have been determined which connect the parameters of the dispersion relation of the lowest mode of internal waves with the integral characteristics of the seasonal thermocline when 10 min30 min, 20 mh150 m, and 0·4 m2/s2 Q5·2 m2/s2.Translated by Mikhail M. Trufanov.  相似文献   

20.
A mathematical model of small organism diffusion around an attractive center is presented. The diffusion equation includes a forcing term which creates a virtual flow of organisms toward the center. Owing to the attractive force, the organisms tend to collect in swarms or patches notwithstanding the diffusive motion of surrounding water.Contribution No. 176 of the Chesapeake Bay Institute, Department of Earth and Planetary Sciences, The Johns Hopkins University. This work was supported by the Office of Naval Research Contract N00014-67-A-0163-0006, Research Project NR083-016, by the U.S. Atomic Energy Commission under Contract AT (30-1) 3109, Document COO-3109-2, and by National Science Foundation Grant, GA-16603.  相似文献   

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