LOWER TO MIDDLE MIOCENE PALYNOLOGY OF THE SHALLOW NEW JERSEY SHELF: EVIDENCE OF ICEHOUSE COOLING

Marine and terrestrial palynomorphs from IODP EXP 313 Sites 27 and 29 on the New Jersey shallow shelf record the establishment of drier continental climates and cooler, more neritic surface waters during the Serravallian. The common presence of gonyaulacoid dinocysts including Apteodinium tectatum, Hystrichokolpoma rigaudiae, Tectatodinium pellitum, Pentadinium laticinctum, Reticulatosphaera actinocoronata, Dapsilidinium pseudocolligerum, Lingulodinium machaerophorum, as well as various Operculodinium, Spiniferites and Impagidinium species in Lower Serravallian and older deposits differs from the pollen-rich Upper Serravallian–Tortonian sediments in which protoperidinioid dinocysts such as Trinovantedinium, Lejeunecysta, Selenopemphix, and Brigantedinium spp. comprise a greater component of the cyst flora. This is consistent with global cooling associated with the growth of ice on Antarctica and the rapid progradation of terrigenous sediments across the New Jersey margin during the early Serravallian.