Seafloor Evidence of Larsen Ice Sheet Breakup
During this field season the National Science Foundation-supported research icebreaker, Nathanial B. Palmer, conducted sea floor studies and water column work in front of the Larsen B ice shelf just prior to its recent breakup. Dr. Eugene Domack (Professor of Geology, Hamilton College), Dr. Glenn Berger (Desert Research Institude, University of Nevada), and Dr. Robert Gilbert (Professor at Queen's University, Canada) coordinated the research.
Sea floor photographs illustrate a seascape littered with a pavement of drop stones most likely released by icebergs from the previous break up of the Larsen B system in 2000 and 1999. The following image is a bottom photograph of the sea floor collected January 2002 in front of the Larsen B ice shelf. This position was recently beneath a much larger Larsen B shelf as recently as two years ago. The bottom shows a seafloor paved with cobbles and pebbles that were probably released from icebergs as the ice shelf disintegrated during a smaller break up event in 1999. Water depth is about 500 m.
Seafloor photograph near Larsen B ice shelf, January 2002
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Preliminary studies of sediment cores from the front of the Larsen B suggest that this break up event is unprecedented in the time since an ice sheet last occupied the entire continental shelf -- roughly 12,000 years before present. See Dr. Domack's research abstract for more information.
