Impact origin of the Chesapeake Bay structure and the source of the North American tektites

C. Koeberl; C. W. Poag; W.U. Reimold; D. Brandt

doi:10.1126/science.271.5253.1263

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Impact origin of the Chesapeake Bay structure and the source of the North American tektites

C. Koeberl·C. W. Poag·W.U. Reimold·D. Brandt

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Abstract

Seismic profiles, drill core samples, and gravity data suggest that a complex impact crater ~35.5 million years old and 90 kilometers in diameter is buried beneath the lower Chesapeake Bay. The breccia that fills the structure contains evidence of shock metamorphism, including impact melt breccias and multiple sets of planar deformation features (shock lamellae) in quartz and feldspar. The age of the crater and the composition of some breccia clasts are consistent with the Chesapeake Bay impact structure being the source of the North American tektites.

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Source-reported bounding extent: 36.85764758564407° to 39.605688178320804° latitude; -77.1240234375° to -75.4046630859375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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C. Koeberl, C. W. Poag, W.U. Reimold, D. Brandt. 1996. Impact origin of the Chesapeake Bay structure and the source of the North American tektites. https://doi.org/10.1126/science.271.5253.1263

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