Amino acid chronology of the Lower Pleistocene deposits of Venta Micena (Orce, Granada, Andalusia, Spain)

This paper deals with a model adjustment for the estimation of age by means of amino acid racemization analysis. Two model families were obtained on the basis of the different genera of molluscs analysed, and were applied to a palaeontological site located in the Cúllar-Baza basin: “Venta Micena” (Orce, Granada). The analytical results obtained from the study of fossil gastropods have provided a very coherent average dating of 983 ± 58 Ky, this coinciding to a large extent with the most widespread palaeontological, geological and stratigraphical datings for the site. There is, however, no agreement with certain recent theories that situate Venta Micena chronologically at the Pliocene-Pleistocene boundary (ca. 1.6 My) or before. The validity of the dating fit was tested on the basis of another classical palaeontological site, Cúllar-Baza, where a coherent dating of 441 ± 27 Ky was obtained.