Geology and tectonic setting of the Fornovolasco area, Alpi Apuane (Tuscany, Italy)

Abstract

The study area is located in the Alpi Apuane (Tuscany, Italy), and extends between N 44° 0′ 49.883′′ –E 10°20′ 23.467′′ (SW corner) and N 44°2′ 53.403′′ –E 10°23′19.175′′ (NE corner). The area shows a pile of tectonic units belonging either to the Apuane metamorphic complex, and Tuscan Nappe, stacked during the Alpine orogeny. The latter is represented by a sedimentary Triassic-Miocene succession, and it is characterized by a large-scale east-dipping monocline, with local excision of stratigraphic terms due to the occurrence of intra-unit low-angle normal faults. The Apuane metamorphic complex is formed by Paleozoic phyllites, post-Variscan magmatic rocks (Fornovolasco Metarhyolite Fm.), and Mesozoic-Tertiary metasedimentary formations. The 1:5000 scale geological map and the cross-sections illustrate the tectonic setting of the Fornovolasco area, resulting from the Tertiary tectono-metamorphic events. In the Fornovolasco area, small Tl-rich pyrite + magnetite ore bodies occur close to the contacts between the Paleozoic basement and the cover metasedimentary formations.