RT Journal Article T1 Discontinuidad sedimentaria del Ordovícico terminal en los Pirineos centrales T1 Stratigraphie unconformity at the uppermost Ordovician in the South Central Pyrenees A1 Gil Peña, Inmaculada A1 Barnolas, Antonio A1 Sanz López, Javier A1 García Sansegundo, Joaquín A1 Palau, J. AB The Upper Ordovician stratigraphic sequence from the Pyrenean Axial Zone starts at a basal conglomerate, known as the Rabassa Fm in the Central and Eastern Pyrenees, that overlays unconformably an undated silicidastic sequence. The vertical stacked fades of that sequence include, over the basal conglomerate layer, greywackes, siltstones and claystones with brachiopod and briozoan fauna of the Upper Caradoc to Lower Ashgill age, reported in the Cava Fm from the Central Pyrenees; micritic and crinoidal limestones dated as Ashgill, the Estana Fm; and, finally, slates with a poorly fossil contends attributed to the Ashgill, the Ansovell Fm. The sequence ends at an unconformity, described in this work, that is overlaid by a discontinuous conglomerate including pebbles of previous Upper Ordovician stratigraphic units. That unconformity and the conglomerate layer are attributed to the erosion of the top of the Upper Ordovician sequence caused by the sea level fall of the glacial Hirnantian stage. The overlain transgressive quarzite, Bar Fm, preludes the well dated black carbonaceous slates of Silurian age and it is attributed to the sea level rise that mark the end of the glacial Hirnantian event PB Sociedad Geológica de España YR 2000 FD 2000 LK http://hdl.handle.net/10272/9769 UL http://hdl.handle.net/10272/9769 LA spa DS Repositorio Institucional de la Universidad de Huelva RD 30 may 2026