Structure and petrography of the Valle Mosso pluton, Sesia Magmatic System, Southern Alps

Abstract

The Valle Mosso pluton (VMP) is a Permian granitic body intruded at intermediate to upper crustal levels in the rocks of the pre-Alpine basement of the Ivrea-Verbano Zone and Serie dei Laghi shortly after the end of Variscan orogeny. As a consequence of Triassic to Jurassic rifting and Alpine orogeny, the VMP and surrounding host rocks have been tilted more than 60° from their original Permian polarity. Thus at present day, the VMP offers the rare opportunity to study a roof-to-floor exposure of a granitic pluton, providing insights into pristine geometry of the magma chamber and its relations to the country rocks. This work presents a new drift and solid map of the VMP and its surrounding host rocks at 1:15.000 scale.

Keywords

• Ivrea-Verbano Zone
• Sesia Magmatic System
• granitic facies
• zoned pluton
• roof-to-floor exposure