A High-Resolution Seismic Survey Across the Balmuccia Peridotite, Ivrea Zone, Italy – Project Dive

Abstract

Summary The Ivrea Verbano Zone (IVZ) is one of the most complete crust–upper mantle geological references in the world, and the Drilling the Ivrea-Verbano zone project (DIVE) aims to resolve the uncertainties below this area. Geophysical anomalies detected across the IVZ indicate that dense, mantle-like rocks are located at depths ca. 1–3 km. One of the goals of this project is the drilling of a 4 km deep borehole that will penetrate the Balmuccia Peridotite (Val Sesia, Italy). The objective of this borehole is to approach, and possibly cross, the crust–mantle transition zone. Two joint geophysical surveys were performed in October 2020 with the goal of obtaining a seismic characterization of the drill site: (1) a deep seismic survey entitled SEismic imaging of the Ivrea ZonE (SEIZE) and (2) a smaller seismic survey at the proposed drill site, entitled High-resolution SEismic imaging of the Ivrea ZonE (HiSEIZE). In this study, we focus on the HiSEIZE data. This project will not only provide site characterization for the DIVE project, but also contribute to understanding the structure of the Balmuccia Peridotite, its changes in depth and its relationship with the crustal-mantle transition.