Articles | Volume 9, issue 2
The Cryosphere, 9, 613–629, 2015
The Cryosphere, 9, 613–629, 2015

Research article 01 Apr 2015

Research article | 01 Apr 2015

Configuration of the Northern Antarctic Peninsula Ice Sheet at LGM based on a new synthesis of seabed imagery

C. Lavoie2,1, E. W. Domack3, E. C. Pettit4, T. A. Scambos5, R. D. Larter6, H.-W. Schenke7, K. C. Yoo8, J. Gutt7, J. Wellner9, M. Canals10, J. B. Anderson11, and D. Amblas10 C. Lavoie et al.
  • 1Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Borgo Grotta Gigante, Sgonico, 34010, Italy
  • 2Department of Geosciences/CESAM, University of Aveiro, Aveiro, 3810-193, Portugal
  • 3College of Marine Science, University of South Florida, St. Petersburg, Florida 33701, USA
  • 4Department of Geosciences, University of Alaska Fairbanks, Fairbanks, Alaska 99775, USA
  • 5National Snow and Ice Data Center, University of Colorado, Boulder, Colorado 80309, USA
  • 6British Antarctic Survey, Cambridge, Cambridgeshire, CB3 0ET, UK
  • 7Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, 27568, Germany
  • 8Korean Polar Research Institute, Incheon, 406-840, Republic of Korea
  • 9Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas 77204, USA
  • 10Departament d'Estratigrafia, Paleontologia i Geociències Marines/GRR Marine Geosciences, Universitat de Barcelona, Barcelona 08028, Spain
  • 11Department of Earth Science, Rice University, Houston, Texas 77251, USA

Abstract. We present a new seafloor map for the northern Antarctic Peninsula (AP), including swath multibeam data sets from five national programs. Our map allows for the examination and interpretation of Last Glacial Maximum (LGM) paleo-ice-flow paths developed on the seafloor from the preservation of mega-scale glacial lineations, drumlinized features, and selective linear erosion. We combine this with terrestrial observations of flow direction to place constraints on ice divides and ice domes on the AP continental shelf during the LGM time interval. The results show a flow bifurcation as ice exits the Larsen B embayment. Flow emanating off the Seal Nunataks (including Robertson Island) is directed toward the southeast, then eastward as the flow transits toward the Robertson Trough. A second, stronger "streaming flow" is directed toward the southeast, then southward as ice overflowed the tip of the Jason Peninsula to reach the southern perimeter of the embayment. Our reconstruction also refines the extent of at least five other distinct paleo-ice-stream systems that, in turn, serve to delineate seven broad regions where contemporaneous ice domes must have been centered on the continental shelf at LGM. Our reconstruction is more detailed than other recent compilations because we followed specific ice-flow indicators and have kept tributary flow paths parallel.