%0 Journal Article
%@ 0094-8276
%A Amoroso, Ortensia
%A Ascione, Alessandra
%A Mazzoli, Stefano
%A Virieux, Jean
%A Zollo, Aldo
%A Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Vesuviano, Naples, Italy,
%A Department of Earth Sciences, Environment and Georesources (DiSTAR), University of Naples Federico II, Naples, Italy,
%A Department of Earth Sciences, Environment and Georesources (DiSTAR), University of Naples Federico II, Naples, Italy,
%A ISTerre, Université de Grenoble I, CNRS, Grenoble, France,
%A Department of Physics, University of Naples Federico II, Naples, Italy,
%D 2014
%F epos:1710
%I American Geophysical Union
%J Geophysical Research Letters
%N 11
%P 3802-3809
%T Seismic imaging of a fluid storage in the actively extending Apennine mountain belt, southern Italy
%U https://episodesplatform.eu/eprints/1710/
%V 41
%X A picture of the upper crustal structure of the Irpinia active faults system in southern Italy was obtained by combining new geological evidences, lithological properties, and microseismicity distribution. P and S wave velocity models indicate high VP/VS and low VP × VS values, suggesting fluid accumulation within a ~15 km wide rock volume where intense microseismicity is located. The 1980 Irpinia, Ms 6.9, earthquake nucleated within the same fault-bounded volume. We suggest that concentration of background seismicity is mainly controlled by high pore fluid pressure. Its increase in fluid-filled cracks around major faults leads to earthquakes' nucleation. Seismic pumping along major faults carries fluids through the conduit system represented by the intensely fractured damage zone. Conversely, the cross-fault barrier behaviour of the low-permeability fault core leads to pore fluid pressures building up within the fault-bounded block, thus producing a positive feedback triggering earthquake nucleation within the volume, which behaves as an “earthquake reservoir.”