Impact effects and regional tectonic insights: Backstripping the Chesapeake Bay impact structure

T. Hayden; M. Kominz; David S. Powars; Lucy E. Edwards; K.G. Miller; J.V. Browning; A.A. Kulpecz

doi:10.1130/g24408a.1

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Impact effects and regional tectonic insights: Backstripping the Chesapeake Bay impact structure

T. Hayden·M. Kominz·David S. Powars·Lucy E. Edwards·K.G. Miller·J.V. Browning·A.A. Kulpecz

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Abstract

The Chesapeake Bay impact structure is a ca. 35.4 Ma crater located on the eastern seaboard of North America. Deposition returned to normal shortly after impact, resulting in a unique record of both impact-related and subsequent passive margin sedimentation. We use backstripping to show that the impact strongly affected sedimentation for 7 m.y. through impact-derived crustal-scale tectonics, dominated by the effects of sediment compaction and the introduction and subsequent removal of a negative thermal anomaly instead of the expected positive thermal anomaly. After this, the area was dominated by passive margin thermal subsidence overprinted by periods of regional-scale vertical tectonic events, on the order of tens of meters. Loading due to prograding sediment bodies may have generated these events.

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Geology Article

Source-reported bounding extent: 36.73888412439431° to 39.70718665682654° latitude; -77.54150390625° to -75.157470703125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

T. Hayden, M. Kominz, David S. Powars, Lucy E. Edwards, K.G. Miller, J.V. Browning, A.A. Kulpecz. 2008. Impact effects and regional tectonic insights: Backstripping the Chesapeake Bay impact structure. https://doi.org/10.1130/g24408a.1

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