32. SIGNIFICANCE OF TURBIDITES AT SITE 767 (CELEBES SEA) AND SITE 768 (SULU SEA)1

The turbidite complexes drilled at Sites 767 and 768 are described and compared. In both cases the complexes are subdivided by sedimentary breaks that can be correlated with regional sedimentary cycle boundaries or regional unconformities. A comparison with the global sea-level chart shows that some breaks correspond to third-order cycles. Other cycle boundaries are obscured by tectonic activity in the area during the period of deposition. Most of the siliciclastic turbidites were derived from source areas rich in quartz detritus: detailed studies show that two source areas provided quartzose detritus to the Sulu Sea in the Miocene. In the Celebes Sea, volcanic source areas were also important source areas of terrigenous detritus. Turbidites of redeposited carbonate sediments occur in both basins.