The Pleistocene epoch (the past 2.55 million years) was marked by large (>100 m) sea-level rises and falls that controlled deposition and erosion of sediment. Geologists' understanding of the relationship between sea level and the sediment record has been limited by the ability to recognize and date Pleistocene packages of sediments called sequences that are bracketed by sea-level falls. In this paper, Kenneth G. Miller and colleagues integrate data from core samples obtained by Integrated Ocean Drilling Program Expedition 313 with new seismic stratigraphic data ("sonograms of the Earth") to interpret Pleistocene sea-level changes on the inner to middle continental shelf and the Hudson shelf valley. Improved age control allows recognition and dating of six Pleistocene sequences. Miller and colleagues suggest that sequences were preserved only during peak high global sea-level events except for a few low stand deposits preserved in eroded (incised) valleys. Incised valleys document more southerly courses of the paleo-Hudson Valleys compare to the modern.
Lithostratigraphy determined from downhole logs in the AND-2A borehole, southern Victoria Land Basin, McMurdo Sound, Antarctica
Sabine Hunze et al. (Thomas Wonik, corresponding author), Leibniz Institute for Applied Geophysics (LIAG), Stilleweg 2, D-30655 Hannover, Germany. Posted online 13 Dec. 2012; http://dx.doi.org/10.1130/GES00774.1.
During the 2007-2008 austral spring season, the ANDRILL Southern McMurdo Sound Project recovered an 1138-m-long core, representing the last 20 million years of glacial hist
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Geological Society of America