A lacustrine carbonate record of Holocene seasonality and climate

Chad A. Wittkop; Jane L. Teranes; Walter E. Dean; Thomas P. Guilderson

doi:10.1130/g30056a.1

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USGS · 70004015

A lacustrine carbonate record of Holocene seasonality and climate

Chad A. Wittkop·Jane L. Teranes·Walter E. Dean·Thomas P. Guilderson

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Abstract

Annually laminated (varved) Holocene sediments from Derby Lake, Michigan, display variations in endogenic calcite abundance reflecting a long-term (millennial-scale) decrease in burial punctuated with frequent short-term (decadal-scale) oscillations due to carbonate dissolution. Since 6000 cal yr B.P., sediment carbonate abundance has followed a decreasing trend while organic-carbon abundance has increased. The correlation between organic-carbon abundance and the sum of March-April-October-November insolation has an r 2 value of 0.58. We interpret these trends to represent a precession-driven lengthening of the Holocene growing season that has reduced calcite burial by enhancing net annual organic-matter production and associated calcite dissolution. Correlations with regional paleoclimate records suggest that changes in temperature and moisture balance have impacted the distribution of short-term oscillations in carbonate and organic-matter abundance superimposed on the precession-driven trends.

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Geology Article

Source-reported bounding extent: 43.26920624914964° to 43.27864254411014° latitude; -85.1333999633789° to -85.11958122253418° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Chad A. Wittkop, Jane L. Teranes, Walter E. Dean, Thomas P. Guilderson. 2009-07-30. A lacustrine carbonate record of Holocene seasonality and climate. https://doi.org/10.1130/g30056a.1

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