16 Paleontology of North America

Added from Discipline submissions.

Monday, 9 March 2026
1:30 PM - 4:30 PM
RCC, 106

Upper Cretaceous Coleraine Formation Chondrichthyan remains from the Hill Annex paleontological site in northern Minnesota, USA

Paper number: 16-3
Program: Technical Sessions
Time: 2:15 PM – 2:30 PM

Authors

Abstract

The Hill Annex mine in northern Minnesota exposes the Upper Cretaceous Coleraine Formation, which formed along the Western Interior Seaway's eastern margin during the mid-Cenomanian. Fossil discoveries at this site include vertebrate remains from fishes, crocodiles, turtles, and plesiosaurs. The Hill Annex Paleontology Project identified six elasmobranch taxa: Protolamna sp., Cretodus gigantea, Archaeolamna sp., Cretalamna cf. C. appendiculata, Squalicorax sp., and Onchopristis dunklei. This area likely marked the northwestern coast of Appalachia, offering key insights into Late Cretaceous marine paleoecology.

Geological Society of America Abstracts with Programs. Vol. 58, No. 1

doi: 10.1130/abs/2026SE-411807

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