Resumen de Reinterpretación estratigráfica y magnetoestratigráfica de la sección del barranco de Orce (cuenca de Baza, Granada): implicaciones para la cronoestratigrafia del Plio-Pleistoceno y la edad de los yacimientos con homínidos de Orce
L. Gilbert, Gary R. Scott, Carles Ferrández i Cañadell
The Barranco de Orce (BO) section in the Baza basin (SE Spain) exposes several fossiliferous layers (0-1 to 0-7) with Plio-Pleistocene micro- and macromammals. Biostratigraphic and magnetostratigraphic data from this and other sections in the basin have been extensively used to calibrate the Plio-Pleistocene chronology based on mammal biozonations, as well as to date the paleontological and archaeological sites in the region, Barranco León (BL), Fuentenueva-3 (FN-3) and Venta Micena (VM). This study shows that the BO section crosses a mega-landslide that produces partial repetitions of the sedimentary sequence. The seven fossiliferous layers (0-1 to 0-7) are actually the repetition of only two (0-6 and 0-7) which are found in situ in the upper part of the ravine. New paleomagnetic results contradict the presence of the Normal event previously reported and assigned to the 'Olduvai' subchron (C2n). The BO magnetostratigraphy can now be correlated with the exclusively Reverse polarity from the adjacent Barranco León (published and new data) and with published Reverse data from the nearby Fuentenueva-3 and Fuentenueva-1 sections. Therefore, all lithic artefacts and paleontological sites in the Orce area are within a Reverse magnetochron, presumably Clr.2r (late Matuyama).
