HR: 0830h
AN: PP31B-0265    [PDF]
TI: Searching for Last Glacial Deep-Sea Polar Carbonates in the Ross Sea Continental slope and Their Relevance to Chronological Constraints
AU: Brambati, A
EM: brambati@units.it
AF: University of Trieste - Dipartimento di Scienze Geologiche, Ambientali e Marine (DiSGAM), Via Weisss, 2, Trieste, 34127 Italy
AU: * Bonaccorsi, R
EM: bonaccor@units.it
AF: University of Trieste - Dipartimento di Scienze Geologiche, Ambientali e Marine (DiSGAM), Via Weisss, 2, Trieste, 34127 Italy
AU: Quaia, T
EM: quaiatu@units.it
AF: University of Trieste - Dipartimento di Scienze Geologiche, Ambientali e Marine (DiSGAM), Via Weisss, 2, Trieste, 34127 Italy
AU: Busetti, M
EM: mbusetti@ogs.trieste.it
AF: Istituto Nazionale di Oceanografia e Geofisica Sperimentale (OGS), Borgo Grotta Gigante 42/c Sgonico, Trieste, 34010 Italy
AB: Abstract Ice-proximal glacial marine sediments from the Antarctic continental margin retain ice rafting events as proxy record for change in the volume and extension of the Antarctic ice sheet throughout glacial-interglacial cycles. However, the sedimentary sequences from the Ross Sea continental margin remain relatively poorly understood and most research has been focused mainly on continental shelf sequences during the last past decades. We present a data set (i.e., X-ray lithology, Multi Sensor Core Logger physical data, and preservation of biogenic carbonates), obtained from six deep-sea cores (1991-1999 Italian Antarctic Research Programme, PNRA - Summer cruises). Specifically, the cores were collected from a) the central Eastern sector (i.e., Core ANTA95-89C, depth: 2056 m, length: 401 cm and Core ANTA99-c22, depth: 2650 m, length: 851 cm); b) the central Western sector (i.e., Core ANTA99-c23; water depth: 2158 m, length: 548 cm; and ANTA99-c24, water depth: 2750 m, length: 811 cm); and c) the North Western sector (i.e., Core ANTA91-08C, and ANTA91-02C) of the Ross Sea Continental slope. Well-preserved calcareous foraminifers (N. pachyderma, sx) in coarse-grained IRD materials sparsely occur and/or are concentrated in discrete layers (i.e., up to 22 cm-thick) of at least three cores (i.e., Cores ANTA91-08, ANTA91-02, and ANTA95-89C, e.g., at 217-238 cm-depth). Some carbonate layers were deposited during a period of time bracketing Stage3/Stage2. In Core 89C foraminifers are associated to multiple ice rafting episodes and likely occurred with oceanographic changes in the properties of slope water masses. The search of well-preserved, in situ-deposited, polar carbonates is demanded for a reliable C-14 AMS dating of late Pleistocene events in the Ross Sea.
DE: 4267 Paleoceanography
DE: 4863 Sedimentation
DE: 9310 Antarctica
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2003 Fall Meeting