Shaken and stirred: Seismic evidence of Chicxulub impact effects on the West Florida carbonate platform, Gulf of Mexico

Claude (Wylie) Poag

doi:10.1130/g39438.1

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Shaken and stirred: Seismic evidence of Chicxulub impact effects on the West Florida carbonate platform, Gulf of Mexico

Claude (Wylie) Poag

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Abstract

A grid of 33 seismic reflection profiles collected on the West Florida Shelf (Gulf of Mexico) reveals evidence of impact-induced seismic shaking and subsequent erosion of the Upper Cretaceous Selma–Pine Key depositional sequence across a wide region (∼102.3 × 10 3 km 2 ) of the buried Cretaceous carbonate platform. These attributes can be traced from outcrops at the Florida Escarpment to locations as far as ∼300 km into the interior of the platform. This evidence suggests a platform-interior provenance for much of the massive Chicxulub impact deposit that borders the base of the Florida Escarpment and adjacent northern Gulf of Mexico continental slope. This report opens a new window on the widespread destructive power of seismic energy released by large bolides striking shallow continental shelves.

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Geology Article

Source-reported bounding extent: 23.85569800975124° to 30.240086360983426° latitude; -89.14306640625° to -81.5185546875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Claude (Wylie) Poag. 2017-10-02. Shaken and stirred: Seismic evidence of Chicxulub impact effects on the West Florida carbonate platform, Gulf of Mexico. https://doi.org/10.1130/g39438.1

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