The Tethyan and Tyrrhenian margin record of the Central Apennines: a guide with insights from stratigraphy, tectonics, and hydrogeology

Abstract

This guide is a 5-day geotraverse across the Central Apennines, which expose the inherited Meso-Cenozoic sedimentary successions and tectonic architecture of the Apennine Tethyan passive margin. This structure was progressively involved into orogenic and post-orogenic tectonics, related to the Tyrrhenian back-arc dynamics. To show the different margin dynamics, we present: 1) sedimentologic and stratigraphic aspects, 2) relations with Neogene compressive and Quaternary extensional structures and 3) a hydrogeological case-study. The trip starts north of Rome, where Quaternary deposits at the transition from marine to continental deposition, including travertines, record the evolution of the Tyrrhenian passive margin. The excursion then moves to the Mesozoic platform margins of the Latium-Abruzzi and Apulia carbonate platforms, where perfectly preserved Cretaceous to Neogene successions occur. The Maiella mountain and Gran Sasso range testify for carbonate production changes, as recorded in facies associations and isotope geochemistry records, related to global climate shifts and regional tectonics. A focus on the hydrogeologic dynamics of the Gran Sasso aquifer is also offered in relation to the current climate change. This guide is the result of a workshop of GeoSed, the Italian Association for Sedimentary Geology, and it also aims at providing a scientific base for geo-touristic explorers.