Leaves in marine turbidites illuminate the depositional setting of the Pliocene Bowden shell beds, Jamaica

The 3.5 Ma Pliocene Bowden shell beds in southeast Jamaica constitute one of the best-known and well-studied paleontological sites in the Greater Antilles. More than 850 species of shelly fossils, dominated by molluscs, have been reported from the unit. Stratigraphic analysis of a newly cleared, continuous section revealed a submarine channel that contains two shelly conglomerates. Elsewhere in the section, newly discovered leaves show variation in modes of transport from mass flow to settling from suspension and are the first such specimens to be reported from Jamaica. The leaves are commonly fragmentary, making taxonomic determination difficult. However, a number of morphotypes are present, including representatives of Lauraceae, Fabaceae, the red mangrove Rhizophora mangle, and, more rarely, Euphorbiaceae, Clethraceae, and Burseraceae. Their occurrence indicates that most of the leaves were sourced from the coastal area, but some were probably derived from further inland. These new observations accentuate the unusual nature of this deposit, which consists of extrabasinal turbidites deposited from hyperpycnal flows.