Aeolian activity - Sea level changes during the last 170.000 years (littoral of Mallorca, Balearic Islands)

Abstract

The Last Interglacial marine terraces bearing Strombus bubonius are characterized by the presence of three highstands during the Isotopic Substage 5e in the island of Mallorca. Two peaks have been recorded by Th/U measurements at 135 ka for the oldest marine unit and 117 ka for the two more recent marine units in the Bay of Palma. Two superimposed marine terraces have been identified in the Bay of Campos that we correlate with the two oldest units of the Bay of Palma. The possibility of correlate these marine terraces wih the aeolian units developed in both basins allows us to establish a relative chronology sequence of the aeolian units formed during the last 170.000 years. At least, two cemented aeolian units pre-Isotopic Substage 5e and another two ones assigned to the Last Interglacial (Isotopic Stage 5) have been identified interbedded with paleosoils. Three aeolian units have been identified in the Last Glacial (I. S. 4 to 2) which present a variable cementation and are separated by erosional surfaces or weak soil formation. At least, three non cemented aeolian units which belong to the Present Interglacial (I. S. 1) have been identified and they are interbedded with blackish soils with high organic matter content. The lower aeolian unit are weakly consolidated and 14C dating on gastropod shells from the top of the unit yielded an age of 4.370±40 1 4C a.BP.