TY  - JOUR
ID  - epos1710
UR  - http://doi.org/10.1002/2014GL060070
IS  - 11
A1  - Amoroso, Ortensia
A1  - Ascione, Alessandra
A1  - Mazzoli, Stefano
A1  - Virieux, Jean
A1  - Zollo, Aldo
Y1  - 2014/06//
N2  - 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.?
PB  - American Geophysical Union
JF  - Geophysical Research Letters
VL  - 41
SN  - 0094-8276
TI  - Seismic imaging of a fluid storage in the actively extending Apennine mountain belt, southern Italy
SP  - 3802
AV  - none
EP  - 3809
ER  -