TURBIDITE FLUX TO THE WESTERN MEDITERRANEAN SEA DURING THE LATE QUATERNARY

It is traditionally held that turbidite emplacement to the deep sea is particularly dynamic during periods of low sea level, coincident with glacial periods. However, other studies have found that turbidite emplacement may be more frequent at times of sea-level change rather than lows. The lithostratigraphy of four long piston cores from the Balearic Abyssal Plain (western Mediterranean Sea) has been examined in detail to elucidate the timing of deposition of this region’s many turbidites. The cores consist predominantly of thick turbidite muds interspersed with thinner pelagic intervals. A stratigraphy has been developed for the pelagic intervals of these cores, based on AMS radiocarbon dating, oxygen isotopes, biostratigraphy (coccolith zones) and calcium carbonate stratigraphy. Based on this stratigraphy we estimate that the cores penetrated to levels of maximum ages of 35, 56, 100 and 110 kyr. The turbidite flux, as expressed by bed thickness, seems to be greater during glacial periods, with the thickest turbidites deposited during times of maximum sea-level change.