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Studies on oysters in relation to the oil industry
112
Oceanographic Abstracts
The material suspended in oceanic waters is usually more fine-grained as compared with HK sediments. In the quiet regions of the ocean granulometric profiles of the suspensions arc similar to tho:.c of the sediments. In places where a sorting of sediment material by currents and waves takes place granulometric contents of suspension greatly differ from sediments. The study of quantitative vertk~al distribution of suspension in vast oceanic regions and of its granulometric contents is used as a basis for an attempt to determine the rate o f subsidence of suspension, e.g. the rate of modern sedimcw tation. In the investigated region of the Indian Ocean this rate proved to be equal to 13 cm per 1000 years. As regards radium and ionium, tbe rate of sedimentation proved to be slightly le.~s than 1 cm per 1000 years. LOUGHNAN F, C. and D. C. CRAIG, 1962. A preliminary investigation of the recem sedimer'as oii the east coast of Australia. Austral. Z Mar. and Freshwater Res., 13 (1): 48 56. Recent sediments from the continental shelf and inner margin of the continental slope for a secliou of the east Australian coast extending from Sydney to Moreton Island have been examined xx.ith respect to composition and particle size distribution. Although insufficient samples are available for conclusive evidence it would appear that there has been very little longshore movement of material and the bulk of the detritus in each sector has been derived from the immediately adjacent land area~ In the Sydney sector there is a suggested variation in clay mineral content with depth which tends to support the differential settling concept. Glauconite, in association with clay pellets, foraminifcrat tests, and fine quartz, occurs in goethite and siderite cemented nodules on the continental slope olT Port Macquarie and ColT's Harbour. LUKYANOV V. V. and L. K. MOlSEY~V, 1961. Distribution of water temperatures in the norihcr~ Indian Ocean. (In Russian; English abstract). Okeanolo~,. lssle~L, Mezhd. Kornitet P~'ot~ed..5~,~'zh~/. Geofiz. Goda, PrezMiume, Akad. Nauk, SSSR, (4): 31-43. The paper gives a preliminary report summarising the data of water temperature on 200 hydrologica~ stations obtained during the 31st cruise of the R/V ViO,az. The works of Vityaz coincided with the period of a set in winter monsoon. This circumstance made it possible for the authors to considci the temperature conditions of the investigated region within the limits of one season. On the basis of the analysis of the maps and of the profiles of temperature distribution :re n~w: come to the following conclusions : 1. Water temperature of the given region is closely connected with the peculiarities of geographicu~ location, namely, with the limitation of African-Asian continental barrier and wilh the close contac! with the vast arid regions of the North-West. 2. The northern part of the ocean is almost completely under the influence of mo,soons, detc~ mining to a considerable degree the main features of the temperature water regime. 3. The applied maps quite evidently testify to the fact that currents play an active role in ~i~v distribution of temperature. 4. Alongside with the advection of the heat by currents, by processes of turbulent and convective exchange the submarine relief has essential significance in horizontal and vertical redistribution ,.H" heat (stable cold spot within the limits of Indian-Australian hollow). LUKYANOVV. V., N. P. NEFEDYEVand Yu. A. ROMANOV,1962. On the scheme of surface current:, in the Indian Ocean during the winter monsoon. Mezhd. Geofiz. Komitet, Prezidiume Akad. ~.'atd,:, SSSR, Rezult. Issled. Programme Mezhd. Geofiz. Goda, Okeanol. IsslecL, 5:19--24 Data on wind deviations in November, December 1959 and in January, February 1960, from tilL' mean one for many years is used to make the scheme of the surface currents of the Indian ()cea~ more exact. The said scheme has been based on the data of observations carried out duri~g t}c 31st cruise of the R/V ViO,az. MACK L. R., 1962. Periodic, tinite-amplitude, axisymmetric gravity waves. J. ~;eophtv. R ~ 67 (2) : 829-844. A study is made of finite-amplitude axisymmetric gravity waves in a circular basin of unitbrm d e p t h Periodic, free, first-mode oscillations ofa nonviscous incompressible liquid are considered. Through the use of Dini expansions, the exact nonlinear governing equations are solved by an iterative procedure which has been carried through the third approximation. The effects of finite amplitude on the surface profile and on the frequency of oscillation are investigated, and the amplitude and angle at the crest of a maximum wave are studied. It is noted that at certain ' critical ' depth-radius ratios the first-mode oscillation may be coupled with a higher-mode motion at an integral multiple of tt~e basic frequency. MACKIN J. G. and S. H. HOeKtNS, 1961. Studies on oysters in relation to the oil irdustry. Ptd;.:
Inst. Mar. Sci., 7 : 1-314. Field and laboratory studies and examination of historical records were made in the tidal waters ot Louisiana to determine the possible role of operations of oil companies on mortality of commercial oysters, Crassostrea virginica. Periods of disastrously high mortality were found in past records, both before and after the beginning of oil operations in the area. According to official figures, 1940
Oceanographic Abstracts
I 13
1947 as a whole was a period of good production, but there was a decline in 1944-1947 due mainly to a sharp drop in St. Bernard Parish, outside the area of major oil operations. Field studies showed that oysters had a consistently high mortality rate throughout the warmer half of the year in the study area, and that mortality rate increased with salinity increase within this area. There was no such correlation with proximity of oil fields. Chemical studies revealed measurable quantities (0.001 to 0.010 per cent dry weight) of unsaponifiable carbon tetrachloride extraclives, called ' hydrocarbons ' by some chemists, in all mud samples tested, including many from locations where no pollution seemed possible. In some cases the quantity of such materials was correlated with the amount of plant debris in samples, and it was found that unsaponifiable material could be extracted by carbon tetrachloride directly from plants in areas distant from any source of petroleum. Within oil fields, the amounts of unsaponifiable carbon tetrachloride extractives were highest (up to 5'8 per centt in mud samples taken near bleedwater outlets and other known centres of pollution, and were correlated with high (up to 0.00578 per cent) ' pentane and heavier hydrocarbons ' as measured independently by a commercial laboratory. Water samples showed minute quantities (approximately 1 ppm) of substances identifiable by routine analysis as ' hydrocarbons ' to be very widely distributed in Louisiana bay waters. These substances showed highest concentrations (up to 226 ppm) in oil field bleedwater and were still high (up to 7.6 ppm) in bay or bayou waters near the point of discharge, but decreased rapidly with distance from the source. ' Hydrocarbon ' content of mud and water was no higher in areas of high oyster mortality than in areas of low mortality. Calculations showed that bleedwater alone could not significantly increase the hydrocarbon content of mud or water on the commercial oyster beds where mortality occurred even if none were destroyed. Bacteriological studies showed that crude oil and its fractions were rapidly destroyed by bacteria living in Louisiana bay muds. Accidental oil spillages were found to cause enough oily taste to make nearby oysters unpalatable for periods ranging from several days to several weeks, but did not kill any oysters on commercial beds. In one case, however, a few intertidal oysters were killed by smothering. Laboratory experiments showed that bleedwater, crude oil, water extracts or emulsions of crude oil,and the principal constituent of drilling mud (barium sulphate) had no effect on survival of oysters over periods of several months, when the concentrations tested were far above the maximum that could be maintained on an oyster bed. Quebracho, another constituent of drilling mud, caused some increase in mortality when used in concentrations much higher than could occur on an oyster bed. In physiological experiments, bleedwater and water extracts of crude oil slowed water pumping and filtering rates of oysters when used at concentrations much higher than could be expected in oystergrowing waters, but these effects were temporary and reversible. In field experiments, spraying oysters repeatedly with crude oil and keeping them under a surface layer of crude oil did not affect survival or growth over a period of months. In other field experiments ovsters were kept for months at various distances from bleedwater outlets, underwater natural gas discharges, and other sources of pollution. A discharge of 6600 barrels of bleedwater per day at Lake Barre increased mortality of oysters as far as 50 to 75 feet from the point of discharge, and apparently caused decrease of shell growth and glycogen storage in oysters as far as 150 feet away, but had no detectable effect at greater distances. Field experiments at Dog Lake, Caillou Island, Lake Pelto, and Bay Sainte Elaine oil fields did not show any adverse effect of bleedwater~ natural gas, or small oil spillages upon the setting, survival, growth, or fattening of oysters. High explosi~.es used for seismographic exploration in the manner prescribed by Louisiana law did not injure oysters either immediately or over a period of months. It was concluded that oil production factors of the kinds tested could not be responsible for the oyster mortalities spread throughout the large area where damage was claimed. The widespread mortalities that did occur during the study period were correlated with high temperature and high salinity, but not with proximity to oil operations. MANDELBAUM H., 1962. Variation of a rotary tide with moon age. J. Geophy.s. Re.s., 67 (I): 249-269. The rotary tidal current at Amrum-Bank lightship in the German Bay is analyzed during 24 equal intervals Between a Greenwich moon transit at 00 h 00 m Greenwich time and the nexl Greenwich moon transit at that time. Both the residual and periodical currents vary in each interval. The variation of the periodic current is comparatively small in amplitude but very pronounced in the phase of the current. The phase variation is rather irregular. The existence of a strong t*_. component in conjunction with the S, component of the current is shown to explain both the weak variation in amplitude and the irregular variation in phase. Strongest current runs appro×imately I day after spring tide in the German Bay. MArlNKOVld>RoJE M. and M. NtcoHd, 1961. Oceanographic researches in the areas of Rovinj and Limski Kanal from 1959-1961. (In Jugoslavian; English sumnlary). Hidro.k,rq[;s'ko/~,Godist!/aka, Split, 1960: 61-67. This work deals with the results of oceanographic measurements (concerning temperature, salinity, oxygen and transparency) for the period March 1959 to December 1960. 'lt represents the continuation of earlier measurements published in Thalassia jugoshwica (1956 and 1959) and in Hi~h'o;,rot2s'ki godL(njak for 1958. Station and methods were the same as given in publications mentioned above.
Oceanographic Abstracts
The material suspended in oceanic waters is usually more fine-grained as compared with HK sediments. In the quiet regions of the ocean granulometric profiles of the suspensions arc similar to tho:.c of the sediments. In places where a sorting of sediment material by currents and waves takes place granulometric contents of suspension greatly differ from sediments. The study of quantitative vertk~al distribution of suspension in vast oceanic regions and of its granulometric contents is used as a basis for an attempt to determine the rate o f subsidence of suspension, e.g. the rate of modern sedimcw tation. In the investigated region of the Indian Ocean this rate proved to be equal to 13 cm per 1000 years. As regards radium and ionium, tbe rate of sedimentation proved to be slightly le.~s than 1 cm per 1000 years. LOUGHNAN F, C. and D. C. CRAIG, 1962. A preliminary investigation of the recem sedimer'as oii the east coast of Australia. Austral. Z Mar. and Freshwater Res., 13 (1): 48 56. Recent sediments from the continental shelf and inner margin of the continental slope for a secliou of the east Australian coast extending from Sydney to Moreton Island have been examined xx.ith respect to composition and particle size distribution. Although insufficient samples are available for conclusive evidence it would appear that there has been very little longshore movement of material and the bulk of the detritus in each sector has been derived from the immediately adjacent land area~ In the Sydney sector there is a suggested variation in clay mineral content with depth which tends to support the differential settling concept. Glauconite, in association with clay pellets, foraminifcrat tests, and fine quartz, occurs in goethite and siderite cemented nodules on the continental slope olT Port Macquarie and ColT's Harbour. LUKYANOV V. V. and L. K. MOlSEY~V, 1961. Distribution of water temperatures in the norihcr~ Indian Ocean. (In Russian; English abstract). Okeanolo~,. lssle~L, Mezhd. Kornitet P~'ot~ed..5~,~'zh~/. Geofiz. Goda, PrezMiume, Akad. Nauk, SSSR, (4): 31-43. The paper gives a preliminary report summarising the data of water temperature on 200 hydrologica~ stations obtained during the 31st cruise of the R/V ViO,az. The works of Vityaz coincided with the period of a set in winter monsoon. This circumstance made it possible for the authors to considci the temperature conditions of the investigated region within the limits of one season. On the basis of the analysis of the maps and of the profiles of temperature distribution :re n~w: come to the following conclusions : 1. Water temperature of the given region is closely connected with the peculiarities of geographicu~ location, namely, with the limitation of African-Asian continental barrier and wilh the close contac! with the vast arid regions of the North-West. 2. The northern part of the ocean is almost completely under the influence of mo,soons, detc~ mining to a considerable degree the main features of the temperature water regime. 3. The applied maps quite evidently testify to the fact that currents play an active role in ~i~v distribution of temperature. 4. Alongside with the advection of the heat by currents, by processes of turbulent and convective exchange the submarine relief has essential significance in horizontal and vertical redistribution ,.H" heat (stable cold spot within the limits of Indian-Australian hollow). LUKYANOVV. V., N. P. NEFEDYEVand Yu. A. ROMANOV,1962. On the scheme of surface current:, in the Indian Ocean during the winter monsoon. Mezhd. Geofiz. Komitet, Prezidiume Akad. ~.'atd,:, SSSR, Rezult. Issled. Programme Mezhd. Geofiz. Goda, Okeanol. IsslecL, 5:19--24 Data on wind deviations in November, December 1959 and in January, February 1960, from tilL' mean one for many years is used to make the scheme of the surface currents of the Indian ()cea~ more exact. The said scheme has been based on the data of observations carried out duri~g t}c 31st cruise of the R/V ViO,az. MACK L. R., 1962. Periodic, tinite-amplitude, axisymmetric gravity waves. J. ~;eophtv. R ~ 67 (2) : 829-844. A study is made of finite-amplitude axisymmetric gravity waves in a circular basin of unitbrm d e p t h Periodic, free, first-mode oscillations ofa nonviscous incompressible liquid are considered. Through the use of Dini expansions, the exact nonlinear governing equations are solved by an iterative procedure which has been carried through the third approximation. The effects of finite amplitude on the surface profile and on the frequency of oscillation are investigated, and the amplitude and angle at the crest of a maximum wave are studied. It is noted that at certain ' critical ' depth-radius ratios the first-mode oscillation may be coupled with a higher-mode motion at an integral multiple of tt~e basic frequency. MACKIN J. G. and S. H. HOeKtNS, 1961. Studies on oysters in relation to the oil irdustry. Ptd;.:
Inst. Mar. Sci., 7 : 1-314. Field and laboratory studies and examination of historical records were made in the tidal waters ot Louisiana to determine the possible role of operations of oil companies on mortality of commercial oysters, Crassostrea virginica. Periods of disastrously high mortality were found in past records, both before and after the beginning of oil operations in the area. According to official figures, 1940
Oceanographic Abstracts
I 13
1947 as a whole was a period of good production, but there was a decline in 1944-1947 due mainly to a sharp drop in St. Bernard Parish, outside the area of major oil operations. Field studies showed that oysters had a consistently high mortality rate throughout the warmer half of the year in the study area, and that mortality rate increased with salinity increase within this area. There was no such correlation with proximity of oil fields. Chemical studies revealed measurable quantities (0.001 to 0.010 per cent dry weight) of unsaponifiable carbon tetrachloride extraclives, called ' hydrocarbons ' by some chemists, in all mud samples tested, including many from locations where no pollution seemed possible. In some cases the quantity of such materials was correlated with the amount of plant debris in samples, and it was found that unsaponifiable material could be extracted by carbon tetrachloride directly from plants in areas distant from any source of petroleum. Within oil fields, the amounts of unsaponifiable carbon tetrachloride extractives were highest (up to 5'8 per centt in mud samples taken near bleedwater outlets and other known centres of pollution, and were correlated with high (up to 0.00578 per cent) ' pentane and heavier hydrocarbons ' as measured independently by a commercial laboratory. Water samples showed minute quantities (approximately 1 ppm) of substances identifiable by routine analysis as ' hydrocarbons ' to be very widely distributed in Louisiana bay waters. These substances showed highest concentrations (up to 226 ppm) in oil field bleedwater and were still high (up to 7.6 ppm) in bay or bayou waters near the point of discharge, but decreased rapidly with distance from the source. ' Hydrocarbon ' content of mud and water was no higher in areas of high oyster mortality than in areas of low mortality. Calculations showed that bleedwater alone could not significantly increase the hydrocarbon content of mud or water on the commercial oyster beds where mortality occurred even if none were destroyed. Bacteriological studies showed that crude oil and its fractions were rapidly destroyed by bacteria living in Louisiana bay muds. Accidental oil spillages were found to cause enough oily taste to make nearby oysters unpalatable for periods ranging from several days to several weeks, but did not kill any oysters on commercial beds. In one case, however, a few intertidal oysters were killed by smothering. Laboratory experiments showed that bleedwater, crude oil, water extracts or emulsions of crude oil,and the principal constituent of drilling mud (barium sulphate) had no effect on survival of oysters over periods of several months, when the concentrations tested were far above the maximum that could be maintained on an oyster bed. Quebracho, another constituent of drilling mud, caused some increase in mortality when used in concentrations much higher than could occur on an oyster bed. In physiological experiments, bleedwater and water extracts of crude oil slowed water pumping and filtering rates of oysters when used at concentrations much higher than could be expected in oystergrowing waters, but these effects were temporary and reversible. In field experiments, spraying oysters repeatedly with crude oil and keeping them under a surface layer of crude oil did not affect survival or growth over a period of months. In other field experiments ovsters were kept for months at various distances from bleedwater outlets, underwater natural gas discharges, and other sources of pollution. A discharge of 6600 barrels of bleedwater per day at Lake Barre increased mortality of oysters as far as 50 to 75 feet from the point of discharge, and apparently caused decrease of shell growth and glycogen storage in oysters as far as 150 feet away, but had no detectable effect at greater distances. Field experiments at Dog Lake, Caillou Island, Lake Pelto, and Bay Sainte Elaine oil fields did not show any adverse effect of bleedwater~ natural gas, or small oil spillages upon the setting, survival, growth, or fattening of oysters. High explosi~.es used for seismographic exploration in the manner prescribed by Louisiana law did not injure oysters either immediately or over a period of months. It was concluded that oil production factors of the kinds tested could not be responsible for the oyster mortalities spread throughout the large area where damage was claimed. The widespread mortalities that did occur during the study period were correlated with high temperature and high salinity, but not with proximity to oil operations. MANDELBAUM H., 1962. Variation of a rotary tide with moon age. J. Geophy.s. Re.s., 67 (I): 249-269. The rotary tidal current at Amrum-Bank lightship in the German Bay is analyzed during 24 equal intervals Between a Greenwich moon transit at 00 h 00 m Greenwich time and the nexl Greenwich moon transit at that time. Both the residual and periodical currents vary in each interval. The variation of the periodic current is comparatively small in amplitude but very pronounced in the phase of the current. The phase variation is rather irregular. The existence of a strong t*_. component in conjunction with the S, component of the current is shown to explain both the weak variation in amplitude and the irregular variation in phase. Strongest current runs appro×imately I day after spring tide in the German Bay. MArlNKOVld>RoJE M. and M. NtcoHd, 1961. Oceanographic researches in the areas of Rovinj and Limski Kanal from 1959-1961. (In Jugoslavian; English sumnlary). Hidro.k,rq[;s'ko/~,Godist!/aka, Split, 1960: 61-67. This work deals with the results of oceanographic measurements (concerning temperature, salinity, oxygen and transparency) for the period March 1959 to December 1960. 'lt represents the continuation of earlier measurements published in Thalassia jugoshwica (1956 and 1959) and in Hi~h'o;,rot2s'ki godL(njak for 1958. Station and methods were the same as given in publications mentioned above.