THE SEDIMENTS OF GUNNERUS RIDGE AND KAINAN MARU SEAMOUNT (INDIAN SECTOR OF SOUTHERN-OCEAN)

Combined bathymetric, sediment echosounding and sediment coring data f rom two expeditions of the RV ''Polarstern'' (ANT-VIII/6, ANT-XI/4) pr ovides the first more comprehensive overview of Cenozoic sedimentation in the remote area of the Gunnerus Ridge and Kainan Maru Seamount off the Antarctic Continent (Indian sector of Southern Ocean). The Neogen e and Oligocene sediment sequences were affected by at least three gen erations of large scale slide and slump events, which occurred around the early/late Pliocene and the early/late Oligocene boundaries and du ring an earlier time period in the Paleogene. Possible triggers for sl umping events might have been changes in the circulation pattern, chan ges in sea level, or earthquakes. Changes in water mass circulation co uld have affected the distribution of sediments since the onset of the Neogene in conjunction with the establishment of the Antarctic Circum polar Current (ACC). The recovered sediments are predominantly biosili ceous mud and ooze: except for early Oligocene and Quaternary sequence s, which contain calcareous nannofossils and foraminifera, respectivel y. The sediments have been deposited at low sedimentation rates rangin g from a few millimeters to centimeters per 1000 yr. (C) 1998 Elsevier Science Ltd. All rights reserved.