Marine Geology
Numerical Modelling, Durham, N. H. October 17, 1972. To he published by National Academy of Sciences. Jordon, A. L. 19731). Varieties and variations of Antarctic Bottom Water. Colioquim on Processes of Formation of Oceanic Deep Waters. October 4-7, 1972. To be published by CNEXO. Gordon, A. L., and R. 1). Goldberg. 1970. Circumpolar characteristics of antarctic waters. Antarctic Map Folio Series, 13. Gordon, A. I,., and P. Tchernia. 1972. Waters of the continental margin off Adélie Coast, Antarctica. Antarctic Research Series, 19: 59-70. Gordon, A. I.., and J. Bye. 1972. Surface dynamic topography of antarctic waters. Journal of Geophysical Research, 77(30): 5993-5999. Hollister, C., and R. Elder. 1969. Contour currents in the Weddell Sea. Deep-Sea Research, 16: 99-101. lvanenkov, V. N., and F. A. Gubin. 1960. Water masses and hydrocheinistry of the western and southern parts of the Indian Ocean. Akad. nauk. SSSR. Trudy, 22: 33-115. Translations in Soviet Oceanography. (American Geophysical union), 22: 27-99. Jacobs, .. .S. 1965. Physical and chemical oceanographic observations in the southern oceans, IISNS Eltanin Cruises 7-15. Lamont-Doherty Geological Observatory, Report, 1CU-1-65. 321 p. Jacobs, S. S. 1966. Physical and chemical oceanographic observations in the southern oceans, IJSNS Eltanin Cruises 16-21. Lam on t-Dohertv Geological Observatory. Report, 1-CU-1-66. 128 p. Jacobs, S. S., and A. F. Amos. 1967. Physical and chemical oceanographic observations in the southern oceans, USNS Eltanin Cruises 22-27. Lam out-Doherty Geological Observatory. Report, 1-CU-1-67. 287 p. Jacobs, S. S., P. M. Bruchhausen, and E. B. Bauer. 1970a. Eltanin reports, Cruises 32-36. l.a mont -Doherty Geological Observatory. 463 p. Jacobs, S. S. et al. 1972. Eltanin reports, Cruises 37-46. Lamont-Doherty Geological Observatory. 490 p. Jacobs, S. S., A. F. Amos. and P. M. Bruchhausen. 1970b. Ross Sea oceanography and Antarctic Bottom Water format ion. Deep-Sea Research, 17: 935-962. Lynn. R., and J . Reid. 1968. Characteristics and circulation of deep and abyssal waters. Deep-Sea Research, 15: 577-598. Lusquinos, A. 1963. Extreme temperatures in the Weddell Sea. Bergen, Norway, Arhok University. No. 23. 19 p. Mackintosh, N. 1946. The Antarctic Convergence and the distribution of surface temperature in antarctic waters, Discovery Report 23: 177-212. Mckee, W. D. 1971. A note on the sea level oscillations in the neighbourhood of the Drake Passage. Deep-Sea Research, 18 (5) : 547-549. Reid, J . I.., and W. Nowlin. 1971. Transport of water through the Drake Passage. Deep-Sea Research, 18(1): 51-64. Scripps Institution of Oceanography et al. 1969. Physical and chemical data from the Scorpio Expedition in the South Pacific Ocean aboard USNS Eltanin Cruises 28 and 29. Sb-REF. Report, 69-56. 95 p. Seabrooke, J ., G. Hufford, and R. Elder. 1971. Formation of Antarctic Bottom Water in the Weddell Sea, journal of Geophysical Research, 76(9): 2164-2178. ichernia, 1'. 1951. Coinpte-rendu preliminaire des observations oceanographiques faites par le batiment polaire "Commandant Charcot" pendant la campagne 1949-1950, Paris, Bulletin (1' Information. COEC 3 (1) : 13-22; 3 (2) 40-57. Wexier, H. 1959. The antarctic convergence-or divergence? In: The Atmosphere and Sea in Motion (Bert Bolin, e(1.) New York, Rockefeller Institute Press. p. 106-120.
May-June 1973
Marine Geology N. D. WATKINS
Graduate School of Oceanography University of Rhode Island Ten years ago, when the Eltan.in program began, marine geology was a simpler science than it is to(lay. At that time it was, in general terms, concerned with the physiography, tectonics, and genesis of the sea floor; the distribution and variation of sediments; and an understanding of the associated roles of organic and inorganic materials and dynamic factors modifying the distribution of these sediments. While this description is still largely valid, it has become virtually impossible to satisfactorily isolate marine geology from marine geophysics, niicropaleoniology, and (to an increasing extent) sonic aspects of physical oceanography. Knowledge of sea floor genesis, tectonics, and overlying sediment thickness and distribution results from geophysical means; micropaleontology is the discipline required to understand sediment origin and variation in time and space; and physical oceanography can provide limits on the water mass dynamics and boundaries, critically effecting sediment type and ])road accumulation patterns. This essential broadening of the science (luring the last decade has been paralleled by the so-called revolution in the earth sciences, which is based almost completely on the recognition of mobility in sea floor and continental configuration. The contribution of the Eltanin marine geology program as summarized here must therefore overlap somewhat with the geophysics and micropaleontology programs in particular as presented elsewhere in this issue. It is still too early to evaluate most of the contributions from the last series of cruises in the southeastern Indian Ocean (between 39 and 55) since they have not yet been published. Background The relative advance in knowledge of the marine geology of the southern ocean provided by the Elta n in program compares favorably with resulting advances in other scientific activities. For example, several hundred hydrological stations had been occupied by the end of the 1950s (Deacon, 1964) whereas according to Ewing and Heezen (1956) only four piston cores with any observable stratigraphic variation had been recovered. Nevertheless, using grab samples or gravity cores, Phillipi (1910), Schott (1939), and Hough (1950, 1956) had described marine sediments from the subant69
arctic sea floor and had recognized the paleoclimatic significance of intercalated silicious ooze, carbon ates, and glacial-marine sediment, but no age control was available. As early as 1937, Deacon (1937) had pointed out that the region between the pack ice and the Subantarctic Convergence was biologically the world's most productive marine environment, with a corresponding sedimentary significance. The most important contribution during the period immediately preceding the Eltanin program was Litizen's (1960) description of bottom sediments including some submarine moraines in the subantarctic of the Indian Ocean. The broad physiographic framework of the southern ocean sea floor was well known by the late 1950s, particularly as the result of cruises of Discovery, as summarized by Heardman (1948) In the early 1960s the glacial history of Antarctica was, with only rare exceptions, considered to be closely related to the Arctic events. Initiation of the present antarctic glaciation was envisaged as oc-
curring during the last 1 to 2 million years. Thu little advance had been made on the ideas of earl) 20th century geologists. Further and wider evaluation of the status oi marine geological and geophysical problems in th subantarctic region, as of the mid 1950s, was published by Ewing and Heezen (1956). Thus the stag( was set for the Eltanin cruises to begin in 1963.
Contributions from the Eltanin program Physiography. The Eltanin program has been instrumental in providing much fine detail in the physiography of the Scotia Sea, South Pacific, and southeast Indian Ocean. Heezen and Johnson (1965) refined earlier surveys of the South Sandwich Trench, during cruise 8. The detailed physiography was supplemented by seismic profiling which revealed, when compared to other trenches, an unexpectedly thin sediment cover. Cruises through 22 enabled Heezen et al.
'HYSIOGRAPHIC PROVINCES SOUTHEAST INDIAN OCEAN
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May-June 1973
Marine Geology N. D. WATKINS
Graduate School of Oceanography University of Rhode Island Ten years ago, when the Eltan.in program began, marine geology was a simpler science than it is to(lay. At that time it was, in general terms, concerned with the physiography, tectonics, and genesis of the sea floor; the distribution and variation of sediments; and an understanding of the associated roles of organic and inorganic materials and dynamic factors modifying the distribution of these sediments. While this description is still largely valid, it has become virtually impossible to satisfactorily isolate marine geology from marine geophysics, niicropaleoniology, and (to an increasing extent) sonic aspects of physical oceanography. Knowledge of sea floor genesis, tectonics, and overlying sediment thickness and distribution results from geophysical means; micropaleontology is the discipline required to understand sediment origin and variation in time and space; and physical oceanography can provide limits on the water mass dynamics and boundaries, critically effecting sediment type and ])road accumulation patterns. This essential broadening of the science (luring the last decade has been paralleled by the so-called revolution in the earth sciences, which is based almost completely on the recognition of mobility in sea floor and continental configuration. The contribution of the Eltanin marine geology program as summarized here must therefore overlap somewhat with the geophysics and micropaleontology programs in particular as presented elsewhere in this issue. It is still too early to evaluate most of the contributions from the last series of cruises in the southeastern Indian Ocean (between 39 and 55) since they have not yet been published. Background The relative advance in knowledge of the marine geology of the southern ocean provided by the Elta n in program compares favorably with resulting advances in other scientific activities. For example, several hundred hydrological stations had been occupied by the end of the 1950s (Deacon, 1964) whereas according to Ewing and Heezen (1956) only four piston cores with any observable stratigraphic variation had been recovered. Nevertheless, using grab samples or gravity cores, Phillipi (1910), Schott (1939), and Hough (1950, 1956) had described marine sediments from the subant69
arctic sea floor and had recognized the paleoclimatic significance of intercalated silicious ooze, carbon ates, and glacial-marine sediment, but no age control was available. As early as 1937, Deacon (1937) had pointed out that the region between the pack ice and the Subantarctic Convergence was biologically the world's most productive marine environment, with a corresponding sedimentary significance. The most important contribution during the period immediately preceding the Eltanin program was Litizen's (1960) description of bottom sediments including some submarine moraines in the subantarctic of the Indian Ocean. The broad physiographic framework of the southern ocean sea floor was well known by the late 1950s, particularly as the result of cruises of Discovery, as summarized by Heardman (1948) In the early 1960s the glacial history of Antarctica was, with only rare exceptions, considered to be closely related to the Arctic events. Initiation of the present antarctic glaciation was envisaged as oc-
curring during the last 1 to 2 million years. Thu little advance had been made on the ideas of earl) 20th century geologists. Further and wider evaluation of the status oi marine geological and geophysical problems in th subantarctic region, as of the mid 1950s, was published by Ewing and Heezen (1956). Thus the stag( was set for the Eltanin cruises to begin in 1963.
Contributions from the Eltanin program Physiography. The Eltanin program has been instrumental in providing much fine detail in the physiography of the Scotia Sea, South Pacific, and southeast Indian Ocean. Heezen and Johnson (1965) refined earlier surveys of the South Sandwich Trench, during cruise 8. The detailed physiography was supplemented by seismic profiling which revealed, when compared to other trenches, an unexpectedly thin sediment cover. Cruises through 22 enabled Heezen et al.
'HYSIOGRAPHIC PROVINCES SOUTHEAST INDIAN OCEAN
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Figure 1. Physiographic map of the southeast Indian Ocean (Hayes and Conolly, 1972).
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