Biostratigraphy of Late Maastrichtian larger foraminifers in Jamaica and the importance of Chubbina as a Late Maastrichtian index fossil
Keywords: Foraminifera, biostratigraphy, Guinea Corn Formation, Upper Cretaceous, Jamica
Abstract. The succession of larger foraminifers from the White Rock River Bridge section of the Guinea Corn Formation (Late Maastrichtian) in Jamaica, West Indies, contains: Sulcoperculina dickersoni (Palmer), Ayalaina rutteni (Palmer), Orbitoides cf. megaloformis Papp & Küpper, Vaughania cubensis Palmer and Chubbina cardenasensis (Barker & Grimsdale). A. rutteni occurs in the lower beds and C. cardenasensis occurs in the upper beds. The orbitoid foraminifer Or. cf. megaloformis is restricted to the middle beds. The White Rock River Bridge Section can be correlated to the standard Guinea Corn successions using lithological/biostratigraphic markers and rudist marker beds, and linked ages derived from Sr-isotope values. This indicates that Or. cf. megaloformis occurs in the last 1.3 Ma of the Cretaceous in the Caribbean and that its evolution was retrograde compared to coeval populations in Europe. The first appearance of Chubbina represents a valuable datum since the genus occurs in various different biofacies (both with and without orbitoid foraminifers) and allows correlation in the Caribbean, Central America and Florida.