Identificación del Pérmico Inferior (Autuniense) en el subsuelo de la cuenca del Ebro, NE de España

Abstract

The lower Permian (Autunian) has not been identified up to now in the subsurface of the Tertiary Ebro Basin because of the scarcity of borehole samples available and the systematic attribution to the Carboniferous without any paleontological data, of the siliciclastic sediments found at the base of some of them, well above the hercynian basement and unmetamorfosed Grey and black shales recovered from cores preserved in the REPSOL archives of the Caspe-1 oil well between meters 1.437 and I .449 have yielded a palynogical assemblage composed by Vittatina cf. costabilis, Potonieisporites novices- bhardwaji, Nuskoisporites sp. and other forms not so well preserved. This association has a Lower Permian (Autunian) age and compares well with other findings in the Iberian Ranges, the Pyrenees and other areas in Iberia, shading a new light on the early stages of evolution of the central and NE parts of Iberia just after the Hercynian orogeny.