Physical properties of ODP Leg 178 sites

We have reanalyzed the porosity, bulk density, and seismic velocity information collected from continental rise Sites 1095, 1096, and 1101 during the drilling of Ocean Drilling Program (ODP) Leg 178 (Fig. F1). The purpose is to provide a comprehensive composite digital set of data readily available for future studies aimed at well-seismic correlation. The work originates from the occurrence of overlapping sets of physical parameters and acoustic velocity collected by different methods (downhole logging, core logging, laboratory determination, and derivation from seismic data) and from different holes at the same site. These data do not always provide the same information because of difficulties encountered at each specific hole or methodological differences. In addition, a basic correlation between these parameters and onsite multichannel seismic (MCS) data is presented.

Composite depth scales and splice tie points of ODP Sites 178-1095 and 178-1096

During Leg 178, multiple advanced piston corer holes were drilled at four sites (1095, 1096, 1098, and 1099). Cores from the holes were correlated on board to produce composite depths and optimal spliced sections, but the time limitations aboard ship caused these to be preliminary. Recomputed composite depths for Sites 1098 and 1099 in Palmer Deep are reported elsewhere in this volume (doi:10.2973/odp.proc.sr.178.2002). This paper reports recomputed composite depths and spliced sections for Sites 1095 and 1096, located on a sediment drift on the continental rise of the Pacific margin of the Antarctic Peninsula. Limits on the validity of the spliced sections arise from limited multiple coverage and possibly from the effects of ocean swell.

Magnetic hysteresis parameters of ODP Site 178-1096 (Table T1)

During Ocean Drilling Program (ODP) Leg 178, we drilled three sites on sediment drifts deposited on the continental rise on the western margin of the Antarctic Peninsula. These hemipelagic drifts were targeted for their potential to preserve a continuous record of the behavior of the West Antarctic Ice Sheet over the last 10 m.y. It has been proposed that drift development is linked to advances and retreats of the Antarctic continental ice sheet (Pudsey and Camerlenghi, 1998, doi:10.1017/S0954102098000376, and references therein; Barker, Camerlenghi, Acton, et al., 1999, doi:10.2973/odp.proc.ir.178.1999). However, the sediment is characterized by a very low carbonate content, with foraminifers restricted to very narrow intervals. This lack of carbonate precludes the construction of a delta18O or CaCO3 stratigraphy, depriving these sites of an important chronologic tool and global ice volume proxy.