Comparison of glacial/interglacial carbonate concentrations in Atlantic sediments


To assess the regional effects of glaciation on sedimentation in the Atlantic Ocean we compare sediment types, distributions, and rates between Recent (core top) and last glacial maximum (LGM: ~18,000 years B.P.) stratigraphic levels. Based upon smear slides and carbonate analyses in 178 cores we find that glacial age carbonate content is generally lower than Recent. During both the Recent and LGM, carbonate content shows an east/west asymmetry with western basins exhibiting lower carbonate values. Input of ice-rafted detritus into the North Atlantic during LGM time interrupts this topographic control on carbonate distribution considerably farther south than at present; in the South Atlantic this effect is minor. Comparison of LGM and Recent sediment distributions indicates that the LGM seafloor was dominated by biogenic oozes, calcareous clays, and clays, while the Recent is dominated by biogenic oozes and marls. Coarse-grained detritus is much more prevalent in LGM sediments, derived not only from glacial input but also from fluvial and aeolian sources. Sedimentation rates, calculated from LGM to Recent sediment thickness in cores, are <4 cm/1000 yr for most of the ocean. Higher rates are typical of the continental margin off the Amazon River, the North American Basin, and a small region off west equatorial Africa.

Supplement to: Balsam, William L; McCoy, F M J (1987): Atlantic sediments: glacial/interglacial comparisons. Paleoceanography, 2(5), 531-542

Related Identifier IsSupplementTo
Metadata Access
Creator Balsam, William L; McCoy, F M J
Publisher PANGAEA
Publication Year 1987
Funding Reference Fourth Framework Programme Crossref Funder ID MAS3980185 Quaternary Environment of the Eurasian North
Rights Creative Commons Attribution 3.0 Unported;
OpenAccess true
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 2 datasets
Discipline Earth System Research
Spatial Coverage (-76.467W, -55.150S, 18.450E, 72.183N); Atlantic Ocean
Temporal Coverage Begin 1954-07-10T00:00:00Z
Temporal Coverage End 1974-08-21T00:00:00Z