According to the Ordinance of the President of the Council of Ministers n. 3519 of 28 April 2006 the seismic zones must be identified by means of maximum acceleration values of the soil (ag), with probability of exceeding 10% in 50 years, referring to rigid soils, characterized by the speed of the cutting waves in the first 30 meters higher at 800 m / s. The values of ag, supplied by the National Institute of Geophysics and Volcanology (INGV) - Milan section, have been calculated for each node of the grid, used to subdivide the source areas of the national territory into cells, whose center of gravity is associated with the point of an earthquake. The standard values of ag (50th percentile) provided by INGV are available with two different resolutions, depending on the step used for the calculation grid (0.05? Or 0.02?), and accompanied by the relative uncertainties expressed in terms of the 16th and 84th percentiles. The Veneto Region has implemented the OPCM 3519/2006 through the DGR n. 71 of 22 January 2008. The nodes of acceleration relating to the regional territory, for a total of 596 points, were extracted from the national dataset, calculated on the grid with a 0.05 step, according to the provisions of OPCM 3519/2006. The geographical coordinates of the acceleration nodes, referring to the ED50 datum, have been converted into Gauss-Boaga fused West. Because of the acquisition methodology and the subsequent data processing used, based on a spatial representation different from that to which the metadata refers, it is not possible to define a homogeneous spatial resolution of the data. Data source: National Institute of Geophysics and Volcanology, Section of Milan.
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