Nonlinear P‐wave tomography of subducted lithosphere beneath central‐southern Apennines (Italy)

Regional gravity anomaly map and crustal model of the Central–Southern Apennines (Italy)

“…Here, tomographic data reveal a low velocity zone between 40 and 200 km (Cimini and De Gori, 2001), and crustal tomographic data indicate anomalous velocity values for the propagation of P waves at depth ranging between 8 and 37 km, this last close to the Moho discontinuity (Chiarabba and Amato, 1996). Here, the lower crust should be close to the melting temperature because of the presence of asthenospheric material identified in the uppermost part of the mantle (Chiarabba and Amato, 1996;Mele et al, 1996Mele et al, , 1997.…”

“…Seismic tomography indicates the presence of an almost continuous high-velocity zone beneath the full length of the Apennines, at depth exceeding 200 km (Spakman, 1990;Amato et al, 1993;Piromallo and Morelli, 1997;Wortel and Spakman, 2000;Lucente et al, 1999;Cimini and De Gori, 2001;Lucente and Speranza, 2001). At shallower depth (40-200 km), the evidence Fig.…”

“…Geological sketch map of peninsular Italy from the Po Plain to the north of the Calabrian arc (after Butler et al, 2004, modified). becomes more controversial and the interpretation of the velocity anomaly pattern is still matter of debate (Spakman, 1990;Lucente et al, 1999;Wortel and Spakman, 2000;Cimini and De Gori, 2001;Lucente and Speranza, 2001).…”

Subduction or delamination beneath the Apennines? Evidence from regional tomography

“…P wave velocity models of the crust and uppermost mantle based on travel times of body waves from regional events were the focus of many investigations, mostly performed by Italian scientists (e.g. Amato et al, 1993;Alessandrini et al, 1995;Selvaggi and Chiarabba, 1995;Di Stefano et al, 1999;Cimini and De Gori, 2001;Orecchio et al, 2011;Gualtieri et al, 2014).…”

Magmatectonic Zonation of Italy: A Tool to Understanding Mediterranean Geodynamics

“…In general, the compressional structures of both the central and the southern Apennines do not show the thin-skinned geometries typical of subduction-related complexes, but rather they are characterized by a thick-skinned style, typical of ensialic deformations, with basement largely involved in the deformation and with only limited amounts of horizontal shortening (van Dijk et al, 2000;Barchi et al, 2001;Noguera and Rea, 2000;Lavecchia et al, 2003). Tomographic models of the mantle beneath the Apennines and the Tyrrhenian show the presence of a highly discontinuous, intra-asthenosphere, high-velocity body, usually assumed to be the Ionian lithosphere subducted in the course of the Apennine compressional phase, but images a r e v e ry d i f f e r e n t i n l e n g th, position and continuity (Spakman et al, 1993;Cimini and De Gori, 2001;Piromallo and Morelli, 2003;Piromallo and Faccenna, 2004). Some alternative, very speculative, hypotheses have been advanced.…”