Formation of the Shelf-edge Cretaceous-Tertiary contact off the southeastern U.S. Coast
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. ?? 1986.
Citation Information
Publication Year | 1986 |
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Title | Formation of the Shelf-edge Cretaceous-Tertiary contact off the southeastern U.S. Coast |
Authors | L. J. Poppe, J. C. Hathaway, R.E. Hall, R.F. Commeau |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Palaeogeography, Palaeoclimatology, Palaeoecology |
Index ID | 70014542 |
Record Source | USGS Publications Warehouse |