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Geo-Marine Letters

, Volume 7, Issue 4, pp 207–215 | Cite as

Unusual bed forms on the North Aleutian Shelf, Bristol Bay, Alaska

  • William C. Schwab
  • Bruce F. Molnia
Article

Abstract

Side-scan sonar records collected over an area of the North Aleutian Shelf, approximately 250 km west of the head of Bristol Bay, Alaska, identified widespread evidence of active sea floor erosion processes, including sediment transport. Thousands of sea floor depressions, many linear and some containing rippled floors, were identified in water depths of 30 to 90 m. The depressions cover approximately 40 percent of the area surveyed. The sea floor depressions are interpreted to be erosional features, and in conjunction with a field of sand waves, exemplify the dynamic nature of the ocenographic processes active on this area of the sea floor.

Keywords

Depression Water Depth Sonar Sediment Transport Erosion Process 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Molnia BF, Schwab WC, Fischer PJ (1982) Parallel linear scours on the Alaskan continental margin (abstract). Geological Society America, Abstracts with Programs 7:569Google Scholar
  2. 2.
    Newton RS, Werner F (1972) Transitional-size ripple marks in Kiel Bay (Baltic Sea). Meyniana 22:89–94Google Scholar
  3. 3.
    Knebel HJ, Needell SW, O'Hara CJ (1982) Modern sedimentary environments on the Rhode Island inner shelf, off the eastern United States. Marine Geology 49:241–256Google Scholar
  4. 4.
    Cacchione DA, Drake DE, Grant WD, Tate GB (1984) Rippled scour depressions on the inner continental shelf off central California. Journal of Sedimentary Petrology 54: 1280–1291Google Scholar
  5. 5.
    Kenyon NH (1970) Sand ribbons of European tidal seas. Marine Geology 9:25–39Google Scholar
  6. 6.
    McKinney TF, Stubblefield WL, Swift DJP (1974) Large-scale current lineations on the Great Egg shoal retreat massive: investigations by side-scan sonar. Marine Geology 17:79–102Google Scholar
  7. 7.
    Johnson EA (1983) Textural and compositional sediment characteristics of the southeastern Bristol Bay continental shelf, Alaska. Master's Thesis, California State University, Northridge, 97 ppGoogle Scholar
  8. 8.
    Pewe TL (1975) Quaternary geology of Alaska. U.S. Geological Survey Professional Paper 835, 145 ppGoogle Scholar
  9. 9.
    Swift DJP, Duane DB, McKinney TF (1973) Ridge and swale topography of the Middle Atlantic Bight, North America: secular response to the Holocene hydraulic regime. Marine Geology 15:227–247Google Scholar
  10. 10.
    Field ME (1980) Sand bodies on coastal plain shelves: Holocene record of the U.S. Atlantic inner shelf off Maryland. Journal of Sedimentary Petrology 50:505–528Google Scholar
  11. 11.
    Stubblefield WL, McGrail DW, Kersey DG (1984) Recognition of transgressive and post-transgressive sand ridges on the New Jersey continental shelf. In: Tillman RW, Siemers CT (eds) Siliclastic Shelf Sediments. Society of Economic Paleontologists and Mineralogists Special Publication 34, pp 1–23Google Scholar
  12. 12.
    Kinder JH, Schumacher JD (1981) Circulation over the continental shelf of the southeastern Bering Sea. In: Coachman LK, Tripp RB (eds) Fifth Annual Report, Bristol Bay Oceanographic Processes. Pacific Marine Environmental Laboratory, Environmental Research Laboratory, National Oceanic and Atmospheric Adminstration, Washington, D.C., pp 53–75Google Scholar
  13. 13.
    Hebard JF (1961) Currents in southeastern Bering Sea. International North Pacific Fisheries Commission Bulletin 5:9–15Google Scholar
  14. 14.
    Lisitsyn AP (1966) Recent sedimentation in the Bering Sea (in Russian). Institute Oceanology Academy Nauk USSR (translated by Israel program for scientific translations, available from U.S. Department of Commerce, Clearinghouse for Federal Scientific and Technical Information, Washington, D.C., 1969), 614 ppGoogle Scholar
  15. 15.
    Brower WA Jr, Searby HW, Wise JL, Davis HF, Prechtal AS (1977) Climatic atlas of the outer continental shelf waters and coastal regions of Alaska. Arctic Environmental Information and Data Center Publication 32:443Google Scholar
  16. 16.
    Quayle RG, Fulbright DC (1975) Extreme wind and wave return periods for the U.S. Coast. Mariners Weather Log, NOAA, U.S. Department of Commerce Publication 19:67–70Google Scholar
  17. 17.
    Molnia BF, Schwab WC, Austin WA (1983) Map of potential geologic hazards on the Nortin Aleutian Shelf (lease sale 92), Bering Sea. U.S. Geological Survey Open-File Report 83-247, scale 1:250,000, 1 sheet and 3 ppGoogle Scholar
  18. 18.
    Field ME, Nelson CH, Cacchione DA, Drake DE (1981) Sand waves on an epicontinental shelf: northern Bering Sea. Marine Geology 42:233–258Google Scholar
  19. 19.
    Hunter RE, Thor DR, Swisher ML (1982) Depositional and erosional features of the inner shelf, northeastern Bering Sea. Geologic en Mijnbouw 61:49–62Google Scholar
  20. 20.
    Clifton HF (1976) Wave formed sedimentary structures: a conceptual model. In: Davis RA Jr, Ethington RL (eds) Beach and Nearshore Sedimentation. Society of Economic Paleontologists and Mineralogists Special Publication 24, pp 126–148Google Scholar
  21. 21.
    Flemming BW (1980) Sand transport and bedform patterns on the continental shelf between Durban and Port Elizabeth (southeast African continental margin). Sedimentary Geology 26:179–205Google Scholar
  22. 22.
    Madsen OS, Grant WD (1976) Sediment transport in the coastal environment. Ralph M. Parson Hydraulics Laboratory, MIT Report No. 209, 105 ppGoogle Scholar
  23. 23.
    Miller MC, McCave IN, Komar PD (1977) Threshold of sediment motion under unidirectional currents. Sedimentology 24:507–527Google Scholar
  24. 24.
    Beardsley RC, Butman B (1974) Circulation on the New England continental shelf: response to strong winter storms. Geophysical Research Letters 1:181–184Google Scholar
  25. 25.
    Boicourt WC, Hacker PW (1976) Circulation of the Atlantic continental shelf of the United States, Cape May to Cape Hatteras. Memoire Society Royale des Sciences de Liege, 16th Series, 10:181–200Google Scholar
  26. 26.
    Niedora AW, Swift DJP (1981) Maintenance of the shoreface by wave orbital currents and mean flow: observations from the Long Island coast. Geophysical Research Letters 8:337–340Google Scholar
  27. 27.
    Field ME, Roy PS (1984) Offshore transport and sand-body formation: evidence from a steep, high-energy shoreface, southeastern Australia. Journal of Sedimentary Petrology 54:1292–1302Google Scholar
  28. 28.
    Murray SP (1970) Bottom currents near the coast during Hurricane Camille. Journal of Geophysical Research 75:4579–4582Google Scholar
  29. 29.
    Foristall GZ, Hamilton RC, Cardon VJ (1977) Continental shelf currents in tropical storm Delia: observations and theory. Journal of Physical Oceanography 7:532–546Google Scholar
  30. 30.
    Smith NP (1977) Near-bottom cross-shelf currents in tire northwestern Gulf of Mexico: a response to wind forcing. Journal of Physical Oceanography 7:617–620Google Scholar
  31. 31.
    Winant CD (1980) Downwelling over the southern California Shelf. Journal Physical Oceanography 10:79–799Google Scholar
  32. 32.
    Rubin DM, McCulloch DS (1980) Single and superimposed bedforms: a synthesis of San Francisco Bay and flume observations. Sedimentary Geology 26:207–231Google Scholar

Copyright information

© Springer-Verlag New York Inc 1987

Authors and Affiliations

  • William C. Schwab
    • 1
  • Bruce F. Molnia
    • 2
  1. 1.U.S. Geological SurveyWoods Hole
  2. 2.Polar Research BoardWashington, D.C.

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