Calcareous nannofossils from the Santa Marta Formation (Upper Cretaceous), northern James Ross Island, Antarctic Peninsula

New occurrences of mollusks from the Santa Marta and Snow Hill Island (Gamma Member) formations, Upper Cretaceous, James Ross Island, Antarctic Peninsula

“…Olivero (2012a) pointed out that the Gamma Member is included in the Snow Hill Island Formation instead of the Santa Marta Formation, as originally defined. The Gamma Member crops out at Santa Marta Cove and Dreadnought Point and is dominated by sandstones beds with scarce Neograhamites primus ammonites, common gastropods, bivalves, and coquinas (Guerra, Concheyro, Lees, Fauth, Carvalho & Ramos, 2015).…”

“…This province included the seas of New Zealand, South America (Patagonia), and Antarctica from the late Cretaceous to late Eocene (e.g., Novas, D'Angelo, O'Gorman, Agnolín, Lírio, & Isasi, 2015;Olivero & Medina, 2000;Zinsmeister 1979Zinsmeister , 1982. More recently, Brazilian researchers have made significant progress to the understanding of the invertebrate (e.g., Pinheiro et al, 2020;Videira-Santos et al, 2020) and vertebrate faunas (e.g., Kellner et al, 2011Kellner et al, , 2019, nannofossils (Guerra et al, 2015), and dinoflagellate cyst assemblage (e.g., Castro & Carvalho, 2015) of this stratigraphic unit.…”