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Surface-sediment maps, just completed, are the first depiction of sea-floor sediment distributions on a systematic and uniform scheme for the entire Pacific basin. Ten dominant sediment types are mapped, using a classification based on calcareous-biosiliceous biogenic components and conventional textural categories for nonbiogenic components (gravel/sand/silt/clay); three minor sediment types distinguish volcanic and organic-skeletal gravels/sands/silts. Primary data were from more than 4,000 Pacific Ocean cores in the Lamont-Doherty Geological Observatory collection. Qualitative smear-slid analyses were done on these cores, using petrographic microscopes combined with laboratory determinations of CaCO3 for quantitative control; many additional data were taken rom unpublished smear-slide descriptions, the World Data Bank, and published information on sea-floor deposits. The maps depict unconsolidated sediments exposed on the ocean floor, presumably at the sediment-water interface, recovered by coring and do not necessarily represent Holocene material. Additional maps showing details of sediment types and the enormous data base, with an explanation of sea-floor sampling techniques and core samples of all 13 sediment types are also available for viewing.
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