Ammonites from the Seabee Formation (Cretaceous) of northern Alaska

Abstract

The Seabee formation, 400-1,800 ft. thick, contains 2 ammonite faunas that are assigned to the Turonian stage of the Upper Cretaceous. These ammonites reveal a mixing of elements from the Atlantic and Pacific faunal realms. The species of Scaphites and Watinoceras are Atlantic types whereas the species of Otoscaphites, Borissiakoceras, and Proplacenticereas seem to have a Pacific source. A connection of the Western Interior seaway with the Pacific Ocean via the Arctic Ocean along northern Alaska seems likely. New species described are Scaphites subdelicatulus, Otoscaphites seabeenis, Borrisiakoceras inconstans, and B. ashurkoffae.