(Table T1) Quaternary, Miocene, and Oligocene calcareous nannofossil stratigraphy of ODP Hole 183-1139A sediments

The distribution of calcareous nannofossils at Ocean Drilling Program Site 1139 on Skiff Bank off the western edge of the Northern Kerguelen Plateau has been used to delineate Quaternary, middle Miocene-middle Oligocene, and lower Oligocene sediments in an expanded 385-m rotary-cored section. Sedimentation rates through most of the Tertiary are high (average = 23 m/m.y.) as a result of clastic input and dilution by high siliceous productivity; chert, however, was encountered in only a single sample. These characteristics, plus the presence of multiple, reasonably well preserved siliceous and calcareous microfossil groups deposited well above the calcite compensation depth, make this site a potential candidate for more detailed coring for paleoceanographic objectives in the future.