From land to sea: multi-scale and multi-resolution analysis of active deformation and seismogenic sources around the coasts of Southern Italy

Abstract

During the last decade, we have blended our individual skills to form a research group devoted to investigating active crustal deformation in areas adjacent to the coast of Southern Italy, with the aim to bridge the gap between the onshore and offshore realms. Our research is based on a multi-scale and multi-resolution approach that includes high-resolution seismics, coastal morpho-tectonics and structural geology, complemented by seismicity, Global Positioning System and InSAR. Need and opportunities of such an endeavor arise from the basic observation that, although most population centers lie close to the coastal areas, very little is known about active structures at the sea. However, hints of active deformation occurring offshore are offered by physical correlation with known or proposed onland seismogenic sources, macroseismic fields of historic events, tsunamis. The capability of our group stems from the long-term experience for most types of marine geological and geophysical surveys, and for structural-stratigraphic analysis of tectonically active areas. We regard the land-sea correlation issue as a key missing link that has hampered, so far, a sound interpretation of active structures in the submerged realm. Starting from this basis, we focused our attention on key sectors of the Southern peninsular Italy and Sicily where active tectonics has been inferred offshore, but detailed information on deformation structures is missing. The core dataset involves very high-resolution, single-channel (SCS) and multi-channel (MCS) data acquired with a series of seismic sources, including multi-tips Sparker array, to provide detailed images of the most recent (e.g. Middle-Late Pleistocene) activity of targeted structures. These data were supplemented by ultra high-res (CHIRP) seismics, and multibeam bathymetric data to get a snapshot of the current deformation close or at the sea-floor, as well as public (VIDEPI project) and unpublished MCS profiles. In addition to data acquired onboard oceanographic research vessels, we complement the dataset by using a Sparker System mounted onboard a trailer-transportable boat suitable to acquire for nearshore surveys. Using additional datasets (seismicity, structural analysis, InSar, GPS etc.), the ultimate goal is a parameterization of active structures (e. g. Ferranti et al., 2014, Barreca et al., 2014), and the calculation of accurate rates of vertical movements (e.g. Pepe et al., 2014), on the basis of case-histories from Calabria and Sicily.