LATE QUATERNARY PALEOCEANOGRAPHY OF THE WESTERN WOODLARK BASIN (SOLOMON SEA) AND MANUS BASIN (BISMARCK SEA), PAPUA-NEW-GUINEA, FROM PLANKTIC FORAMINIFERA AND RADIOCARBON DATING

Foraminiferal assemblages and radiocarbon dates from three cores colle cted in the western Woodlark Basin and one from the Manus Basin have p rovided information on late Quaternary sedimentation rates and charact eristics of water masses. In the western Woodlark Basin, where turbidi tes and slumps are present, sedimentation rates vary from a few tens o f cm/1000 year to 140 cm/1000 year, with background rates decreasing e astwards from New Guinea from 7 cm/1000 year to 3.7 cm/1000 year. In t he Manus Basin during the past 16,000 years the sedimentation rate was 15.5 cm/1000 year. In the western Woodlark Basin the lysocline has de epened by at least 900 m over the past 23,500 years. It was above 2680 m before 23,500 years ago; at 3145 m about 13,000 years ago and is no w at 3500 m. During the past 30,000 years variations in the mean annua l temperatures of surface waters in the western Woodlark Basin were ab out 3 degrees C, and about 4.5 degrees C in the Manus Basin. There wer e cool intervals at 19,500 and 13,000 years ago. A poorly developed ea rly Holocene warm interval 10,000-8500 years ago was followed by a coo ler interval with a minimum 8000 years ago. The Holocene climatic opti mum occurred 5000 years ago with temperatures higher than at present. (C) 1997 Elsevier Science B.V.