SEMINARIS DE LA FACULTAT DE GEOLOGIA I L'INSTITUT DE CIÈNCIES DE LA TERRA 'JAUME ALMERA'
Within a homogeneous and isotropic crust affected by extension Anderson theory predicts that normal faults should form with dip angles of about 60°. However in many extensional settings geological and geophysical data show that crustal extension, under vertical σ1 trajectories, is accommodated on normal faults dipping significantly less than 60°. In order to explain movements on faults oriented at high angles to the regional σ1, i.e. misoriented faults, some weakening processes should be present. In this seminar I will focus on some low-angle normal faults from the Apennines of Italy and I will 1) present field and microstructural evidences of the chemico-physical processes responsible of fault weakening; 2) document fault weakening and associated slip behaviour on the grounds of laboratory experiments on friction; 3) compare structural and laboratory inferences with geophysical data from active low-angle normal faults.

Dia: 9 de Novembre de 2011
Hora: 12h
Lloc: Sala d'actes de l'Institut Jaume Almera