(Table 1) Age determination of ODP Leg 166 holes

Thick, late Quaternary sediment sections were recovered at several sites on the leeward slope of Great Bahama Bank during Leg 166 of the Ocean Drilling Program. These sections have paleoceanographic records with potentially high temporal resolution. To make an initial assessment of the records corresponding to the Holocene highstand of sea level, we have identified and dated the sediments from the four upper slope sites (1004, 1005, 1008, and 1009) that were deposited during the period of time which spans the last glaciation through the Holocene. Age identifications are based upon the abundances of the Globorotalia menardii complex of planktonic foraminifera, the stable oxygen isotopic ratios of bulk sediment and the planktonic foraminifera Globogerinoides ruber, and AMS C-14 dating of bulk sediment. Comparison of these data with the sediment lithologic and geoacoustic properties shows that consistent stratigraphic relationships exist at each site: The uppermost interval of aragonite-rich sediments corresponds to the Holocene highstand of sea level (i.e. oxygen isotope stage 1) and these sediments are underlain by a relatively thin interval of aragonite-poor, partially lithified sediments which corresponds to the last glaciation when sea level was significantly lower than today (i.e. oxygen isotope stages 2-4). The Leg 166 upper slope sites possess carbonate accumulation and paleoceanographic proxy records with very high temporal resolution, with Sites 1004, 1008, and 1009 appearing to have the greatest stratigraphic integrity. Comparison of core and high-resolution seismic profile data establishes the Holocene nature of the uppermost seismic unit in the stratigraphic package of the western slope of Great Bahama Bank.

(Table XIII-2, Page 166) Physical characteristics of manganese nodules collected in the Pacific Ocean during cruise GH77-1 of R/V Hakurei Maru

In the GH77-1 cruise, manganese nodules were obtained from 31 stations among 37 total ones. Here are reported the preliminary results of the observation mainly done on-board. Special attention was paid to confirming the applicability of the nodule type classification tentatively established in the previous GH76-1 cruise and to delineating the pattern of the nodule distribution and clarifying its relation to the geological factors, such as topography, surface sediment types, and substrate stratigraphy. In addition, a short description of the obtained rock samples from a few stations is included in this chapter.