Imaging the polarity switch between large seismogenic normal faults in the southern Apennines (Italy).

The transition between the central and southern Apennines (Italy) is marked, among other regional features, by a dramatic shift (from SW-dipping to NE-dipping) of the vergence of the large (more than 25 km long) seismogenic normal faults, responsible for M>6 pre-historical and historical earthquakes. Also, in the exact area where such accommodation occurs, in 2005 a low magnitude (M<3) seismic sequence took place along a short stretch of a long-lived transverse structure running across this transition zone. We believe this sequence sheds light on the geometry and the role of the interaction between these seismogenic domains. [ABSTRACT FROM AUTHOR]