Mechanical heterogeneities in Umbria-Marche Apennines Thrusts: a field and experimental perspective

Telemaco Tesei (a,c), Cristiano Collettini (b,c), Massimiliano R. Barchi (a) & Giuseppe di Stefano (c)
(a) Department of Earth Sciences, University of Perugia, Perugia, Piazza Università 1, 06100 Perugia, Italy E-mail: telemaco.tesei@ingv.it (b) Department of Earth Sciences , Sapienza University of Rome, Piazzale Aldo Moro, 5, 00185, Rome, Italy. (c) Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143, Rome, Italy.

The link between actual fault rock/structures and multi-mode slip behavior of faults, such as earthquakes, tremors, creep and others is controversial. We addressed this topic for carbonate-hosted, mature faults carrying out field and microstructural analyses and performing friction experiments on three thrusts exposed in the Umbria-Marche Apennines (Central Italy). Geological observations and mechanical data are in good agreement, suggesting heterogeneous faults characterized by patches with strong materials and localized deformation surrounded by weak materials with distributed deformation.

Thrust, fault structure, experiments, friction, healing