Comparison of ice-rafted debris and physical properties in ODP Site 1094 (South Atlantic) with the Vostok ice core over the last four climatic cycles

Author(s): Kanfoush, Sharon L.; Hodell, David A.; Charles, Christopher D.; Janecek, Thomas R.; Rack, Frank R.
Author Affiliation(s): Primary:
University of Florida, Department of Geological Sciences, Gainesville, FL, United States
University of Florida, United States
Syracuse University, United States
Scripps Institution of Oceanography, United States
Florida State University, United States
Joint Oceanographic Institutions, United States
Volume Title: Southern Ocean paleoceanography; insights from Ocean Drilling Program Leg 177
Volume Author(s): Gersonde, Rainer, editor; Hodell, David A.
Source: Southern Ocean paleoceanography; insights from Ocean Drilling Program Leg 177, edited by Rainer Gersonde and David A. Hodell. Palaeogeography, Palaeoclimatology, Palaeoecology, 182(3-4), p.329-349. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0031-0182 CODEN: PPPYAB
Note: In English. 80 refs.; illus., incl. 1 table, sketch map
Summary: Visual counts of ice-rafted debris (IRD), foraminifera, and radiolaria were made for ∼1500 samples in Site 1094 spanning the last four climatic cycles (marine isotope stages 1-11). Most, but not all, of the IRD variability is captured by whole-core physical properties including magnetic susceptibility and γ-ray attenuation bulk density. Glacial periods are marked by high IRD abundance and millennial-scale variability, which may reflect instability of ice shelves in the Weddell Sea region. Each interglacial period exhibits low IRD and high foraminiferal abundance during the early part of the interglacial, indicating relatively warm sea-surface temperatures and reduced influence of sea ice. IRD increases and foraminiferal abundances decrease during the latter part of each interglacial, indicating a return to more glacial-like conditions. Glacial terminations I and V are each characterized by a step-wise reduction in ice-rafting punctuated by a brief pulse in IRD delivery and reversal in δ18O. The coarse fraction of the sediment is dominated by ash and radiolaria, and the relative abundance of these components is remarkably similar to the concentration of Na+ in Vostok. Each of these variables is believed to be controlled mainly by sea-ice cover, thereby providing a means for sediment-ice core correlation.
Year of Publication: 2002
Research Program: ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Antarctic Ocean; Antarctic ice sheet; Antarctica; Atlantic Ocean; Cenozoic; Climate change; Climate forcing; Foraminifera; Glacial geology; Ice cores; Ice rafting; Ice sheets; Interglacial environment; Invertebrata; Isotope ratios; Isotopes; Leg 177; Microfossils; Milankovitch theory; O-18/O-16; ODP Site 1094; Ocean Drilling Program; Orbital forcing; Oxygen; Paleoclimatology; Physical properties; Pleistocene; Protista; Quaternary; Radiolaria; South Atlantic; Southern Ocean; Stable isotopes; Upper Pleistocene; Vostok Station
Coordinates: S720000 S720000 E0970000 E0970000
S531049 S531049 E0050749 E0050749
Record ID: 2002052692
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands