TH230/U234 Dates of Late Pleistocene Marine Fossils from the Mediterranean and Moroccan Littorals

摘要

Apparent ages of fossil molluscs based on Th230/U234 ratios show sufficient internal consistency and agreement with independent evidence of age to justify exploration of their usefulness. Preliminary results from samples from Mediterranean and Moroccan littorals suggest (1) that the Anfatian stage of Morocco and the first appearance of Strombus bubonius in the Mediterranean are both >300,000 years old, (2) that sea level stood high between 140,000 and 125,000 years B.P., and (3) that several Tyrrhenian deposits and the Ouljian stage of Morocco record a non-glacial interval of high sea level 75,000-90,000 years B.P. Internal consistency in the results reported here, and correspondence with other estimates of the absolute age of times of high sea level, lend credibility to the absolute ages derived from Th230/U234 ratios. (Author)