Glacial age marsh, Lafayette Park, Washington, D.C.

A.S. Knox

doi:10.1126/science.165.3895.795

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Glacial age marsh, Lafayette Park, Washington, D.C.

A.S. Knox

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Abstract

Organic sediments beneath historic Lafayette Park mark the site of a freshwater marsh which bordered the Potomac River when it was 15 meters above its present level. Plant microfossils and ice-rafted boulders indicate a climate much colder than now. The carbon-14 age of more than 45,000 years and palynological studies suggest an early Wisconsin age.

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Source-reported bounding extent: 38.895445868036376° to 38.898329727607745° latitude; -77.03895019340989° to -77.03378503481444° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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A.S. Knox. 1969. Glacial age marsh, Lafayette Park, Washington, D.C.. https://doi.org/10.1126/science.165.3895.795

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