부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.tecto.2008.07.008 Byline: Alfio ViganA[sup.2] (a), Gianni Bressan (b), Giorgio Ranalli (c), Silvana Martin (a) Keywords: Focal mechanisms; Seismotectonics; Tectonic stress and strain; Southern Alps Abstract: A set of 41 focal mechanisms (1989-2006) from P-wave first polarities is computed from relocated seismic events in the Giudicarie-Lessini region (Southern Alps). Estimated hypocentral depths vary from 3.1 to 20.8 km, for duration magnitudes (M.sub.D) in the range 2.7-5.1. Stress and strain inversions are performed for two seismotectonic zones, namely G (Giudicarie) and L (Lessini). This subdivision is supported by geological evidence, seismicity distribution, and focal mechanism types. The available number of data (16 in G, 22 in L) does not make possible any further subdivisions. Seismotectonic zones G and L are undergoing different kinematic regimes: thrust with strike-slip component in G, and strike-slip in L. Principal stress and strain axes in each sub-region show similar orientations. The direction of maximum horizontal compressive stress is roughly perpendicular to the thrust fronts along the Giudicarie Belt in zone G, and compatible with right-lateral strike-slip reactivation of the faults belonging to the Schio-Vicenza system in zone L. On the whole, kinematic regimes and horizontal stress orientations show a good fit with other stress data from focal mechanisms and breakouts and with geodetic strain rate axes. Author Affiliation: (a) Department of Chemical and Environmental Sciences, Insubria University, Via Valleggio 11, 22100, Como, Italy (b) Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, Dipartimento Centro Ricerche Sismologiche, Via Treviso 55, 33100, Cussignacco (Udine), Italy (c) Department of Earth Sciences and Ottawa-Carleton Geoscience Centre, Carleton University, Ottawa, Canada K1S 5B6 Article History: Received 15 March 2008; Revised 10 July 2008; Accepted 13 July 2008