Estratigrafía del llerdiense en la región de Tremp (cuenca de Graus-Tremp, NE de España)

Abstract

A new stratigraphic subdivision of the Herdian stratotype in the Tremp basin is proposed. The Figols Croup has been defined as a new unit which comprises a succession of shallow marine sediments about 750 m thick. This group is formed by three formations and nine members and was deposited between 55.7 Ma and 52.5 Ma, contemporaneously to the emplacement of the Montsec thrust sheet. A new correspondence between macroforaminifera biozones and lithostratigraphic units is proposed. The Figols Croup records a vertical evolution characterized by the superposition of carbonatic, litharenitic and arkosic materials which coincides with the three defined formations