A new Early Permian ichnocoenosis from the "Gruppo vulcanico atesino" (Mt. Luco, Southern Alps, Italy)

Abstract

A new Early Permian ichnocoenosys from the “Gruppo vulcanico atesino” (Mt. Luco, Southern Alps, Italy) The “Gruppo vulcanico atesino” (GA) belongs to the Lower Permian and reaches an areal extent of 2000 km between the Periadriatic Lineament to NW and the Valsugana Line to the South, in the central Southern Alps. It consists of a continental volcano-sedimentary succession formed in an environment strongly conditioned by a contemporary tectonic activity. Geological mapping has revealed sedimentary levels laid down in small basins, preserved at different stratigraphical levels inside the volcanic succession. The deposits of one of the basins (Luco Basin) yielded a new, moderately well-preserved, Early Permian vertebrate ichnofauna. The ichnocoenosis includes three ichnotaxa ascribed to reptile trackmakers (cf. Amphisauropus, Dromopus lacertoides, Dromopus cf. D. didactylus) and one (cf. Batrachichnus) ascribed to amphibian. The radiometric age interval of the volcanites (Mt. Luco Fm.) that include the footprints-rich levels (Luco Basin) is between 279.6±1.5 My and 278.4±1.5 My. The ichnocoenosis here described results older than the Tregiovo ichnocoenosis and younger than the Collio Basin one. Consistently, it increases the confidence on the interval of occurrence of the Early Permian ichnoassemblage known in the region.