Seismic hazard values are expressed in terms of maximum horizontal component of the expected ground shaking (ag=fraction of gravity acceleration) with 10% probability of exceedance in 50 years, referred to rocky soils (Vs30>800 m/s, class A, paragraph 3.2.1 in Ministerial Decree September 14th 2005). The ag values have been estimated according two grid points not overlapping: a) with step 0.05 degrees, according the requirements of the Ordinance 3519 (Official Gazette n.108, May 11th 2006), with...