DISTRIBUTION OF CALCAREOUS NANNOPLANKTON DURING NEOGENE ON THE BASIS OF DATA FROM SITE-516 IN THE RIO-GRANDE RISE

The calcareous nannoplankton was studied on the basis of 44 samples of the deep sea sediments from site 516. The thickness of the Neogene se ction was 169.5 meters. The nannofossil distribution in the section wa s studied, and biostratigraphic zones and subzones from NN2 to NN18 (C N1-CN12) by E. Martini and D. Bukry were determined. Two stratigraphic al hiatuses took place: one in the middle of the Late Miocene (0.4 Ma) , and another - from the end of the Late Miocene to the beginning of t he Pliocene (2.6 ma or more).