(Appendix) Coarse-sand fraction abundance and composition at DSDP Site 86-579 and Hole 86-580

DOI

The abundance and composition of the coarse-sand fraction (250 µm-2 mm) of samples from Deep Sea Drilling Project Sites 579 and 580 were investigated to determine the chronology of ice rafting at these locations. The ice-rafting signal at these sites is reduced relative to the generalized ice-rafting chronology of the North Pacific (Kent et al., 1971) because of increased distance to the ice-rafting source areas. These data, however, do record the general increase in ice-rafting importance as sediment age decreases, especially between 0 and 1.0 m.y. ago. In addition, peaks in ice-rafting importance since 1.0 m.y. ago at Sites 579 and 580 are generally synchronous with periods of major ice-rafting influence throughout the North Pacific. The first occurrence of ice-rafted debris at the Matuyama/Gauss magnetic boundary supports a proposed age of approximately 2.47 m.y. for the onset of major Northern Hemisphere glaciation. The coarse-sand fraction at Sites 579 and 580 contains a significant component of non-ice-rafted material, particularly biogenic particles and volcanic pumice. Under these conditions, the standard assumption that the weight percent of the coarse-sand fraction reflects variations in ice-rafting importance may not be valid. For samples taken at some distance from the source of ice-rafted debris, both the abundance and the composition of the coarse-sand fraction must be considered to obtain a valid measure of the influence of sediment transport via ice rafting.

Supplement to: Krissek, Lawrence A; Morley, Joseph J; Lofland, Darlene K (1985): The occurrence, abundance, and composition of ice-rafted debris in sediments from Deep Sea Drilling Project Sites 579 and 580, Northwest Pacific. In: Heath GR; Burckle LH; et al. (eds.), Initial Reports of the Deep Sea Drilling Project, Washington (U.S. Govt. Printing Office), 86, 647-655

Identifier
DOI https://doi.org/10.1594/PANGAEA.802673
Related Identifier https://doi.org/10.2973/dsdp.proc.86.128.1985
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.802673
Provenance
Creator Krissek, Lawrence A; Morley, Joseph J; Lofland, Darlene K
Publisher PANGAEA
Publication Year 1985
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 1227 data points
Discipline Earth System Research
Spatial Coverage (153.836W, 38.627S, 153.976E, 41.624N); North Pacific
Temporal Coverage Begin 1982-06-01T00:00:00Z
Temporal Coverage End 1982-06-06T00:00:00Z