Formation of the Shelf-edge Cretaceous-Tertiary contact off the southeastern U.S. Coast

L. J. Poppe; J.C. Hathaway; R.E. Hall; R.F. Commeau

doi:10.1016/0031-0182(86)90010-6

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Formation of the Shelf-edge Cretaceous-Tertiary contact off the southeastern U.S. Coast

L. J. Poppe·J.C. Hathaway·R.E. Hall·R.F. Commeau

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Abstract

Submarine erosion, associated with changes in position of the proto-Gulf Stream, was the dominant mechanism controlling the formation of the Cretaceous-Tertiary unconformity in AMCOR borehole 6004. Paleontologic evidence indicates that this unconformity, which is marked by a gravelly-sand enriched in glauconitic and phosphoritic concretions, represents a hiatus of about 7 m.y. Both Cretaceous and Paleocene sediments contain middle-outer neritic foraminiferal assemblages that become more diverse with distance from the contact. Of the elemental abundances measured, Al, Ba, Co, Fe, Ga, K, Mg/Ca, Mo, Ni, P, Sr/Ca, V, Y, and Zn show a strong positive correlation with proximity to the contact, probably as a result of the concentration of authigenic and heavy minerals present as lag sediments on the erosion surface.

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Palaeogeography, Palaeoclimatology, Palaeoecology Article

Source-reported bounding extent: 28.801837148662386° to 33.57557193127283° latitude; -81.93483520257233° to -78.23544887113383° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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L. J. Poppe, J.C. Hathaway, R.E. Hall, R.F. Commeau. 1986. Formation of the Shelf-edge Cretaceous-Tertiary contact off the southeastern U.S. Coast. https://doi.org/10.1016/0031-0182(86)90010-6

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