New magnetostratigraphic evidence for the age of Acheulean tools at the archaeo-palaeontological site Solana del Zamborino (Guadix – Baza Basin S Spain)

摘要

The sedimentary record in the Guadix-Baza Basin (southern Spain) has proved to be a great source of information for the Miocene through the Pleistocene periods, due to the abundant faunal remains preserved, in some cases associated with lithic tools. The Solana del Zamborino (SZ) section has been the subject of controversy ever since a magnetostratigraphic analysis resulted in an age of 750–770 Kyr for Acheulean tools, a chronology significantly older than the ~600 Kyr established chronology for the first Acheulean record in Europe. Although recent findings at the “Barranc de la Boella” site (north-east of the Iberian Peninsula) seem to indicate that an earlier introduction of such technique in Europe around 0.96–0.781 Ma is possible, the precise age of the classical site at SZ is still controversial. The aim of this paper is to constrain the chronology of the site by developing a longer magnetostratigraphic record. For this purpose, we carried out an exhaustive sampling in a new succession at SZ. Our results provide a ~65 m magnetostratigraphic record in which 4 magnetozones of normal polarity are found. Our new magnetostratigraphic data suggest an age range between 300–480 Kyr for the lithic tools, closer to the age of traditional Acheulean sites in Europe.