GNGTS 2013 - Atti del 32° Convegno Nazionale

Fig. 2 – Morphostructural zoning map of the Po plain and M5+ earthquakes occurred from 1093 to 2012. Lines depict lineaments of different rank (as in Fig. 1). Dots mark the epicenters of M5+ earthquakes from the UCI catalog. Tab. 1 – Parameters used for recognition of seismogenic nodes in the Po plain and corresponding thresholds for their discretization. Parameters Thresholds of discretization Po plain interiors Po plain boundaries A)Topographic parameters Maximum topographic altitude, m (Hmax) Minimum topographic altitude, m (Hmin) Relief energy, m (ΔH) (Hmax - Hmin) Distance between the points Hmax and Hmin, km (L) Slope, (ΔH/L) B) Geological parameters The portion of the node area covered by soft (quaternary) sediments, % ,(Q) C) Parameters from the morphostructural map The highest rank of lineament in a node, (HR) Number of lineaments forming a node, (NL) Distance to the nearest 1st rank lineament, km, (D1) Distance to the nearest 2nd rank lineament, km, (D2) Distance to the nearest node, km, (Dn) D) Morphological parameter (Mor) This parameter is equal to one of the following six values in accord with the morphology within each node: 1 - mountain and plain (m/p) 2 - piedmont and plain (pd/p) 3 - plain only (p) E) Gravity parameters Maximum value of Bouguer anomaly, mGal ,(Bmax) Minimum value of Bouguer anomaly, mGal, (Bmin) Difference between Bmax and Bmin, mGal , (ΔB) 30 20 5 30 27 200 27 34 2.1 70 98 2 2 30 0 20 15 20 1.5 -65 -20 -110 -85 30 50 901 1600 70 180 906 1560 2 34 32.2 61.8 15 25 1 2 0 28 45 20 1.5 -40 -100 -60 20 40 90 GNGTS 2013 S essione 2.1