Determination of and preliminary results from the high-resolution physical properties record of the AND-1B sediment core from beneath Ross Ice Shelf, Antarctica
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چکیده
Determination of and preliminary results from the high-resolution physical properties record of the AND-1B sediment core from beneath Ross Ice Shelf, Antarctica" (2007). Summary A more than 1200 m long sediment core was drilled beneath McMurdo Ice Shelf near Ross Island (Antarctica) in austral summer 2006/07 (ANDRILL-MIS Project). High-resolution whole-core physical properties were determined as one set of parameters to describe changes in the depositional system over the sedimentation period of about 12 myrs incorporated in the core. Four parameters were measured using a multi-sensor core logger: acoustic velocity, wet-bulk density, non-contact electrical resistivity and magnetic susceptibility. Data quality was routinely controlled by measurement of standards. Deviations from the reference values are minimal with regard to the whole spectrum of sediment data points and no offsets between core diameter intervals are obvious. Almost all boundaries between lithostratigraphic units are in good agreement with changes in the physical properties record. For the depth interval between 140-300 mbsf the physical properties indicate rhythmic changes in the environmental system with alternations of diatomite and diamictite sequences. Abstract 130,4 p.
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