Geomorphological map of the San Pellegrino Pass (Dolomites, Northeastern Italy)

Abstract

This paper discusses the geomorphological features of the northern slope of the San Pellegrino Pass (Autonomous Province of Trento, Northern Italy), located in a well-known area of the Dolomites between the San Pellegrino and the Biois valleys, and illustrates the annexed geomorphological map at a scale of 1:10,000. Geomorphological features are strongly influenced by the structural setting and range from ancient glacial and periglacial landforms to gravitational and karst morphologies. During the Last Glacial Maximum, a glacier from the west transfluenced through the pass. Numerous traces of subsequent events testify to the presence of independent glacial tongues flowing south-east, fed by glacial cirques occurring in the Costabella ridge. The chronological reconstruction suggests that almost all of the moraines generated by these glaciers can be attributed to the Younger Dryas (Egesen Stadial). A core drilled in Lèch de Campagnola (Campagnola Lake) provided two radiocarbon ages, the oldest dating back to 11,258-11,686 cal. yrs. BP. This indicates that since the very early Holocene environmental conditions had rapidly changed, and glacial processes in the area had concluded. The two ages represent the oldest Holocene radiocarbon dates in a sedimentary sequence of the Dolomites. There are also tongue-shaped rock glaciers, some of them very large in size; their aspect unequivocally indicates that they developed in a continuum from glacial to periglacial processes, evolving from debris- covered glaciers to ice-core rock glaciers. The study enriches our knowledge of the geomorphology of a wellknown sector of the eastern Dolomites, still lacking a systematic and detailed geomorphological survey. Moreover, considering the high tourist activity of the area, it also represents a tool to spread knowledge of the morphological evolution and the environmental problems through geotourist maps that can be derived from this geomorphological map. Finally, the availability of a large-scale geomorphological map can also contribute to the evaluation of geomorphological hazards for a safer use and management of the territory.