L’Aquila earthquake was a complex seismic event characterized by its main shock on 6th April 2009 with magnitude Mw=6.3 and many foreshocks and aftershocks that stroke the whole Aterno River Valley from November 2008 up to September 2009. The huge amount of strong-motion records collected by permanent and temporary stations placed in the valley show a heterogeneous seismic hazard scenario related to different damage levels. With respect to the seismological features of the records within the “crater” (that is the portion of the Aterno Valley which suffered the strongest struck), they show “near field” and “near source” characters although the same records provide differentiated amplification effects among neighboring sites. Geological relieves and direct and indirect in field testing were performed for micro-zoning purposes soon after the main shock. The outcomes of these two year studies produced satisfactory results that have been collected as guidelines for identifying the areas showing homogeneous seismic response. Nonetheless, some questions have not been answered yet, that are (1) how much geo-lithological conditions affect the seismic response within “near field” areas and (2) which means can be used to predict the recorded amplifications. This paper focuses and discusses on some results carried out at a few sites, such as Onna and L’Aquila municipalities and proposes operating strategy to detect the local amplification effects within near field areas.
L’Aquila seismic event on 6th April 2009: site effects and critical points in microzonation activity within the Aterno Valley Municipalities
Rainone M. L.;SIGNANINI, Patrizio;VESSIA, Giovanna;
2013-01-01
Abstract
L’Aquila earthquake was a complex seismic event characterized by its main shock on 6th April 2009 with magnitude Mw=6.3 and many foreshocks and aftershocks that stroke the whole Aterno River Valley from November 2008 up to September 2009. The huge amount of strong-motion records collected by permanent and temporary stations placed in the valley show a heterogeneous seismic hazard scenario related to different damage levels. With respect to the seismological features of the records within the “crater” (that is the portion of the Aterno Valley which suffered the strongest struck), they show “near field” and “near source” characters although the same records provide differentiated amplification effects among neighboring sites. Geological relieves and direct and indirect in field testing were performed for micro-zoning purposes soon after the main shock. The outcomes of these two year studies produced satisfactory results that have been collected as guidelines for identifying the areas showing homogeneous seismic response. Nonetheless, some questions have not been answered yet, that are (1) how much geo-lithological conditions affect the seismic response within “near field” areas and (2) which means can be used to predict the recorded amplifications. This paper focuses and discusses on some results carried out at a few sites, such as Onna and L’Aquila municipalities and proposes operating strategy to detect the local amplification effects within near field areas.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
