Small magnitude earthquake sequences and seismic swarms in the Northern Apennines (central Italy): new observations from the analysis of Montefeltro seismicity

San Francisco, CA, USA

We collected P and S phases from 516 earthquakes.
Earthquakes were integrated with new pickings
selected from the temporary array and relocated
using the Hypoellipse code [Lahr, 1999].
The 1-D velocity model used in this work is based
on the study by Santini et al. [2011], which was
determinated for the solution of focal mechanisms
of central-northern Marche.
To constrain the subcrustal seismicity of the area,
we added the layers between 35 and 100 km to link
the structure of crustal velocity with the superficial
part of the upper mantle, as defined in the spherical
global models such as iasp91, ak135 [Kennett et al., 1995]

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