The term Tremp Group reflects more appropriately than the former Tremp Formation the stratigraphic
complexity of the so-called «Garumnian» of the south Pyrenean Tremp-Graus basin. However, the current
definitions of some of the formal units making up the Tremp Group are somewhat inconsistent. New field
observations and, mainly, the discovery of the carbon isotopic excursion of the Initial Eocene Thermal
Maximum, permit to correlate key sections of the Tremp Group with far more reliability than was hitherto
possible. On the light of that correlation we revise the original definitions of the Talarn, Esplugafreda and
Claret Formations, and of some of its members, and propose modifications to clarify their boundaries and
ages