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Magnetic measurements near the deep ocean floor
Oceanographic Abstracts
1049
HANSEN WALTER, 1964. lJber den Zusammenhang zwischen Windgeschwindigkeit und Wasserstandserh6hung. In: Studies on Oceanography dedicated to Professor Hidaka in Commemoration o f his Sixtieth Birthday, 386-388. The elevation of sea-level caused by wind is discussed. This is not only a function of the wind velocity and direction but depends also to a considerable extent on the wind duration. An example is given showing this relationship in the North Sea. HARDY ALISTERC., 1964. Plankton studies and our understanding of major changes in the great oceans. In : Studies on Oceanography dedicated to Professor Hidaka in Commemoration o f his Sixtieth Bhthday, 550 560. The development of a means of recording the changing plankton over wide ocean spaces by automatic samplers towed below the surface by ships on different lines is briefly described. The advantage of using such meteorological-like simultaneous observations is discussed, and some of the recent results of an extension of the system into and across the North Atlantic Ocean are given as an illustration of the method at work. HARRISON MARKandROBERTPLUTCHOl,:,1965. Scattering th~ory for one-dimensional problems. d. acoust, Soc. Am., 37 (1) : 84 - 89. An analytical method is given that allows one to compute for an acoustic wave the reflection and transmission coefficients for a scattering layer such as might be encountered in the ocean where the sound velocity varies in a complicated manner. The technique described is called the method of partial waves since there is some analogy with the corresponding technique for three-dimensional scattering. The problem of a scattering layer is treated by an integral-equation method. The first iteration of this integral equation is obtained for a simple case where the exact answer is also known and is shown to give good agreement. This result is compared to the first Born approximation and is shown to be considerably more accurate. The method can also be used in idealized cases where boundary conditions are known. One such simple case is considered and the method developed in this paper is shown to yield the exact answer. The method is a quite general mathematical technique and can be adapted to the analogous problem in optics, quantum mechanics, electromagnetic, and seismic waves. HARTNOVV R. G., 1963. The biology of Manx spider crabs. Proc. zool. Soc., Lond., 141 (3): 423~96. The biology of 14 species of spider crabs occurring in the Isle of Man area was investigated, particular attention being given to their distribution, food, moulting cycle and breeding. The distribution of a species is related to the type of bottom deposit, and members of a genus have complementary distributions. There is a variable degree of diet selection and food availability is an important factor in determining distribution. The moult of puberty, which in all cases is the terminal ecdysis, is well defined in all species. There are two patterns of breeding, one continuous throughout the year, the other with a single annual hatching. With few exceptions the relative growth of the chelae is allometric, exhibiting marked sexual dimorphism. HASSAN EL SAYED MOHAMED, 1964. A three dimensional model of the wind driven horizontal velocities in the North Atlantic Ocean. In : Studies on Oceanography dedicated to Pro/~'ssor Hidaka in Commemoration of his Sixtieth Birthday, I0-14. Starting with the wind stress over the North Atlantic Ocean computed by Hidaka (1958), a model of the three dimensional picture of the horizontal velocity is developed. This is presented as a possible climatological atlas for the currents. Limitations of the method are discussed. HEEZEN BRUCE C. and G. LEONARD JOHNSON, 1963. A moated knoll in the Canary Passage. Dt. hydrogr. Z. 16 (6): 269-272. A 100-fathoms high one-mile-wide elongate knoll approximately ten nautical miles long lies in 650 fins ( 1200 m) depth in the Canary Passage. The long axis is parallel to the axis of the passage. The knoll is flanked by a moat 5 to 20 fins deep which in turn is surrounded by a gentle arch or ridge o f similar height. Although similar moats have been interpreted as a result of downward isostatic adjustments of islands and seamounts, this moat is considered the product of bottom scour by ocean currents. F[Fss FREDERICK R., 1964. A shear pin weak-link assembly for oceanographic use. Deep-Sea Res., l l (4): 623-624. Weak links have been fabricated for use on dredges or devices where it is desirable to release or tumble the device should it become entangled or snagged on the bottom, The device is a shear pin-holder with provision for pins of different shear strengths for varying loads. HEmTZLER J. R., 1964. Magnetic measurements near the deep ocean floor. Deep-Sea Res., 11 (6): 891-898. During the period 11 to 14 June 1963, while searching for the sunken submarine Thresher in the Northwest Atlantic, a proton precession magnetometer was towed 20 m above the ocean floor.
1050
Ooeanographic Abstracts
A total intensity contour map of a small area of the bottom reveals a geological anomaly of approximately 25 gammas amplitude and approximately 2 km in extent. When away from this anomaly the field strength increases with depth as appropriate for a geomagnetic dipole. Near the anomal~ the field strength increases with depth at a rate greater than that appropriate for a geomagnetic dipole. Time variations in total magnetic intensity on the ocean floor appear to follow closely lime variatio~:~, of the horizontal component of field strength on land. HELLAND P., 1963. Iemperature and salinity variations in the upper layers at Occat~ Weathc~ Station M (66 N, 2')E). Acta UJ~iv. Ber7an., Mat.-naturv. serie, 1963, No. 16:26 pp. Also in: Collected Papers, [f2,ather Ship Station M, 66 'N, 2"E, Geoph)'s. Inst., Univ. Bergen, 1963. Observations of temperature and salinity down to 150 m collected at Ocean Weather Station M during the years 1948-1958 have been studied. Mean values of temperature and salinity for periods of approximately ten days are presented, and the seasonal and year to year variations of temperature and salinity discussed. The investigation shows that the water masses are mainly o f Atlantic origin. but that sometimes, especially in summer. Norwegian Coastal Water may also be f o u n d HERMAN SI1)NI,Y S. and Jos~I'H A. MIHURSK',:, 1964. Infestation of the copepod h'~r!:a :m:',.:~ with the stalked ciliate Zootkamlfium. Sciem'e, 146 (3643): 543-544. An entire population of the copepod Acartia tonsa in the Patuxent River, Maryland, was infested with a stalked protozoan of the genus Zoothamnium. Each copepod had 25 to 200 ciliates attached around the appendages. The infestation occurred at the time when Acartia totlsa was being replacer! as the dominant copepod by Acartia clattsi.
H~CKS STEACV 1)., t964. Tidal wave characteristics of Chesapeake Bay. ('he.s~p~'a/,,~:.Sci., 5 ( ~ : 103-115. A description of the tidal wave in greater Chesapeake Bay is presented through the use of charI~ depicting distributions of cotidal hour, range, current hour, type, sequence, and inequalities. Qualitatively, the distributions are explained in terms of the standard theory of reflected wave~. Due to its small depth-to-length ratio, Chesapeake Bay accommodates slightly more than one semidiurnal tidal wave at all times. Shallow water tides are significant in the upper reache~ of the Potonmc and James Rivers. HIDE R., 1964. The viscous boundary layer at the free surface of ;1 rotating baroclific fluid. Tellus, 16 (4) : 523 -529. The properties of the viscous boundary layer at the free surface of a rotating baroclinic fluid arc analyzed and compared with those of the well-known Ekman boundary layer at a rigid surface. Although the agesotrophic components o f the flow in the free surface boundary layer are weaker than in the Ekman layer, there are problems o f practical interest in which their effects are not negligible. HIRSCH PETER and ASHLEY M. CARTER, 1965. Mathematical models for the prediction of SOFA R propagation effects. J. acoust. Soc. Am., 37 (1 l: 90--94. Various analytical models for the acoustic speed-versus-depth profile of the ocean near tire sound. channel axis are examined with a view toward predicting the characteristic features of SOFAR transmission, especially the time dispersion of lhe multiple SOFAR arrivals. It is found that these features are accounted for only by very specilic models. In particular, the one analytically tractabic model that leads to the observed resuhs appears to be given by c :~ ~ c~~ (1 !az]~). 1 with t o HOESE H. D. and R. S. JONES, 1963. Seasonality of larger animals in a Texas turtle grass cowmlunit~ Publs. Inst. mar. Sci., Port Aransm', 9:37 47. A one-year study was made of macro-invertebrates and tishes in the grass flats of Redlish Bay, Texas, using a drop-net quadrat. The major invertebrate was Penaeus duorarum and the major fish Lagodon rhomboides. Population level o f nearly all species suddenly increased to high levels and decreased as rapidly to former low levels. Heaviest populations occurred in spring (4.9 gm/m z in May) with a secondary high in fall (3'5 gm/m 'z in mid-September and October). Lowest populations occurred in sunanaer (0.8 gm/m 2 in mid-July to mid-August) and winter (0.46 gm/m 2 in Januaryl. Total population densities were correlated best with water level, but summer and winter minimums coincided with many adverse factors. The fauna was similar to that o f Florida west coast bays where the major habitat type is the same. HOLMES C. W. and H. G. GOODEt.I~, 1964. The prediction of strength in the sediments of St. Andrew Bay, Florida. J. sedim. Petrol., 34 (1): 134-143. The cohesion, or strength, of sediments from cores taken at ten sites in St. Andrew Bay, Florida, have been investigated as a function o f a number of other sediment characteristics by multiple linear regression and non-linear regression. Cohesion was measured by unconfined compression of vane shear tests. Strength in these sediments is tbund to decrease as sediment water content increases, t~ increase with depth in the core, and to increase with an increase in the ratio of kaolinite to illite. All o f these variables are linearly related to strength. Water content, depth in core and the ratio o f K/I are associated with a number of second order effects, most o f which both increase and decrease strength. Penetration depends upon sediment water content, mean grain size, sorting, and void ratio.
1049
HANSEN WALTER, 1964. lJber den Zusammenhang zwischen Windgeschwindigkeit und Wasserstandserh6hung. In: Studies on Oceanography dedicated to Professor Hidaka in Commemoration o f his Sixtieth Birthday, 386-388. The elevation of sea-level caused by wind is discussed. This is not only a function of the wind velocity and direction but depends also to a considerable extent on the wind duration. An example is given showing this relationship in the North Sea. HARDY ALISTERC., 1964. Plankton studies and our understanding of major changes in the great oceans. In : Studies on Oceanography dedicated to Professor Hidaka in Commemoration o f his Sixtieth Bhthday, 550 560. The development of a means of recording the changing plankton over wide ocean spaces by automatic samplers towed below the surface by ships on different lines is briefly described. The advantage of using such meteorological-like simultaneous observations is discussed, and some of the recent results of an extension of the system into and across the North Atlantic Ocean are given as an illustration of the method at work. HARRISON MARKandROBERTPLUTCHOl,:,1965. Scattering th~ory for one-dimensional problems. d. acoust, Soc. Am., 37 (1) : 84 - 89. An analytical method is given that allows one to compute for an acoustic wave the reflection and transmission coefficients for a scattering layer such as might be encountered in the ocean where the sound velocity varies in a complicated manner. The technique described is called the method of partial waves since there is some analogy with the corresponding technique for three-dimensional scattering. The problem of a scattering layer is treated by an integral-equation method. The first iteration of this integral equation is obtained for a simple case where the exact answer is also known and is shown to give good agreement. This result is compared to the first Born approximation and is shown to be considerably more accurate. The method can also be used in idealized cases where boundary conditions are known. One such simple case is considered and the method developed in this paper is shown to yield the exact answer. The method is a quite general mathematical technique and can be adapted to the analogous problem in optics, quantum mechanics, electromagnetic, and seismic waves. HARTNOVV R. G., 1963. The biology of Manx spider crabs. Proc. zool. Soc., Lond., 141 (3): 423~96. The biology of 14 species of spider crabs occurring in the Isle of Man area was investigated, particular attention being given to their distribution, food, moulting cycle and breeding. The distribution of a species is related to the type of bottom deposit, and members of a genus have complementary distributions. There is a variable degree of diet selection and food availability is an important factor in determining distribution. The moult of puberty, which in all cases is the terminal ecdysis, is well defined in all species. There are two patterns of breeding, one continuous throughout the year, the other with a single annual hatching. With few exceptions the relative growth of the chelae is allometric, exhibiting marked sexual dimorphism. HASSAN EL SAYED MOHAMED, 1964. A three dimensional model of the wind driven horizontal velocities in the North Atlantic Ocean. In : Studies on Oceanography dedicated to Pro/~'ssor Hidaka in Commemoration of his Sixtieth Birthday, I0-14. Starting with the wind stress over the North Atlantic Ocean computed by Hidaka (1958), a model of the three dimensional picture of the horizontal velocity is developed. This is presented as a possible climatological atlas for the currents. Limitations of the method are discussed. HEEZEN BRUCE C. and G. LEONARD JOHNSON, 1963. A moated knoll in the Canary Passage. Dt. hydrogr. Z. 16 (6): 269-272. A 100-fathoms high one-mile-wide elongate knoll approximately ten nautical miles long lies in 650 fins ( 1200 m) depth in the Canary Passage. The long axis is parallel to the axis of the passage. The knoll is flanked by a moat 5 to 20 fins deep which in turn is surrounded by a gentle arch or ridge o f similar height. Although similar moats have been interpreted as a result of downward isostatic adjustments of islands and seamounts, this moat is considered the product of bottom scour by ocean currents. F[Fss FREDERICK R., 1964. A shear pin weak-link assembly for oceanographic use. Deep-Sea Res., l l (4): 623-624. Weak links have been fabricated for use on dredges or devices where it is desirable to release or tumble the device should it become entangled or snagged on the bottom, The device is a shear pin-holder with provision for pins of different shear strengths for varying loads. HEmTZLER J. R., 1964. Magnetic measurements near the deep ocean floor. Deep-Sea Res., 11 (6): 891-898. During the period 11 to 14 June 1963, while searching for the sunken submarine Thresher in the Northwest Atlantic, a proton precession magnetometer was towed 20 m above the ocean floor.
1050
Ooeanographic Abstracts
A total intensity contour map of a small area of the bottom reveals a geological anomaly of approximately 25 gammas amplitude and approximately 2 km in extent. When away from this anomaly the field strength increases with depth as appropriate for a geomagnetic dipole. Near the anomal~ the field strength increases with depth at a rate greater than that appropriate for a geomagnetic dipole. Time variations in total magnetic intensity on the ocean floor appear to follow closely lime variatio~:~, of the horizontal component of field strength on land. HELLAND P., 1963. Iemperature and salinity variations in the upper layers at Occat~ Weathc~ Station M (66 N, 2')E). Acta UJ~iv. Ber7an., Mat.-naturv. serie, 1963, No. 16:26 pp. Also in: Collected Papers, [f2,ather Ship Station M, 66 'N, 2"E, Geoph)'s. Inst., Univ. Bergen, 1963. Observations of temperature and salinity down to 150 m collected at Ocean Weather Station M during the years 1948-1958 have been studied. Mean values of temperature and salinity for periods of approximately ten days are presented, and the seasonal and year to year variations of temperature and salinity discussed. The investigation shows that the water masses are mainly o f Atlantic origin. but that sometimes, especially in summer. Norwegian Coastal Water may also be f o u n d HERMAN SI1)NI,Y S. and Jos~I'H A. MIHURSK',:, 1964. Infestation of the copepod h'~r!:a :m:',.:~ with the stalked ciliate Zootkamlfium. Sciem'e, 146 (3643): 543-544. An entire population of the copepod Acartia tonsa in the Patuxent River, Maryland, was infested with a stalked protozoan of the genus Zoothamnium. Each copepod had 25 to 200 ciliates attached around the appendages. The infestation occurred at the time when Acartia totlsa was being replacer! as the dominant copepod by Acartia clattsi.
H~CKS STEACV 1)., t964. Tidal wave characteristics of Chesapeake Bay. ('he.s~p~'a/,,~:.Sci., 5 ( ~ : 103-115. A description of the tidal wave in greater Chesapeake Bay is presented through the use of charI~ depicting distributions of cotidal hour, range, current hour, type, sequence, and inequalities. Qualitatively, the distributions are explained in terms of the standard theory of reflected wave~. Due to its small depth-to-length ratio, Chesapeake Bay accommodates slightly more than one semidiurnal tidal wave at all times. Shallow water tides are significant in the upper reache~ of the Potonmc and James Rivers. HIDE R., 1964. The viscous boundary layer at the free surface of ;1 rotating baroclific fluid. Tellus, 16 (4) : 523 -529. The properties of the viscous boundary layer at the free surface of a rotating baroclinic fluid arc analyzed and compared with those of the well-known Ekman boundary layer at a rigid surface. Although the agesotrophic components o f the flow in the free surface boundary layer are weaker than in the Ekman layer, there are problems o f practical interest in which their effects are not negligible. HIRSCH PETER and ASHLEY M. CARTER, 1965. Mathematical models for the prediction of SOFA R propagation effects. J. acoust. Soc. Am., 37 (1 l: 90--94. Various analytical models for the acoustic speed-versus-depth profile of the ocean near tire sound. channel axis are examined with a view toward predicting the characteristic features of SOFAR transmission, especially the time dispersion of lhe multiple SOFAR arrivals. It is found that these features are accounted for only by very specilic models. In particular, the one analytically tractabic model that leads to the observed resuhs appears to be given by c :~ ~ c~~ (1 !az]~). 1 with t o HOESE H. D. and R. S. JONES, 1963. Seasonality of larger animals in a Texas turtle grass cowmlunit~ Publs. Inst. mar. Sci., Port Aransm', 9:37 47. A one-year study was made of macro-invertebrates and tishes in the grass flats of Redlish Bay, Texas, using a drop-net quadrat. The major invertebrate was Penaeus duorarum and the major fish Lagodon rhomboides. Population level o f nearly all species suddenly increased to high levels and decreased as rapidly to former low levels. Heaviest populations occurred in spring (4.9 gm/m z in May) with a secondary high in fall (3'5 gm/m 'z in mid-September and October). Lowest populations occurred in sunanaer (0.8 gm/m 2 in mid-July to mid-August) and winter (0.46 gm/m 2 in Januaryl. Total population densities were correlated best with water level, but summer and winter minimums coincided with many adverse factors. The fauna was similar to that o f Florida west coast bays where the major habitat type is the same. HOLMES C. W. and H. G. GOODEt.I~, 1964. The prediction of strength in the sediments of St. Andrew Bay, Florida. J. sedim. Petrol., 34 (1): 134-143. The cohesion, or strength, of sediments from cores taken at ten sites in St. Andrew Bay, Florida, have been investigated as a function o f a number of other sediment characteristics by multiple linear regression and non-linear regression. Cohesion was measured by unconfined compression of vane shear tests. Strength in these sediments is tbund to decrease as sediment water content increases, t~ increase with depth in the core, and to increase with an increase in the ratio of kaolinite to illite. All o f these variables are linearly related to strength. Water content, depth in core and the ratio o f K/I are associated with a number of second order effects, most o f which both increase and decrease strength. Penetration depends upon sediment water content, mean grain size, sorting, and void ratio.