TURBIDITE DEPOSITION RECORD AND ITS MECHANISM SINCE 150 KABP IN WESTERN PHILIPPINE SEA: TURBIDITE DEPOSITION RECORD AND ITS MECHANISM SINCE 150 KABP IN WESTERN PHILIPPINE SEA

Abstract

Core MD06-3052 was taken from the continental slope off the Luzon Island in the western Philippine Sea.Multiple proxies such as AMS14C dating,sediment grain size and foraminiferal oxygen isotope were used to reveal the 5 turbidite events since 150 kaBP.The turbidites have coarser grain size than the normal layers,mostly composing of sand and silt.The occurrence time of the 5 turbidite events was calculated by AMS14C dating and oxygen isotope as 13.3,20.4,34.3,41.7 and 121.8 kaBP,separately,of which the latter 4 ones occurred in the low sealevel stages of the last glacial,especially in MIS 2-3,and the earliest one at the relatively low sealevel stage in MIS 5e,indicating that rapid sealevel oscillation during low sealevel stages was probably the main cause of the turbidite events.However,the steep slope may be a favorable topography for the sediment instabilities in Core MD06-3052.