GNGTS 2015 - Atti del 34° Convegno Nazionale

The contour map of Quaternary sedimentary cover thickness ( z ) was outlined from the f 0 contour map and by using the Eq. 1 (Fig. 3). Conclusions. We report the empirical correlation in the Quaternary Western L’Aquila Plain (WAP) of the velocity-depth function between the sedimentary cover thickness ( z ) and the seismic noise resonance frequency ( f 0 ), coming from a great quantity of measurements, which has beenprocessed by applying the Horizontal to Vertical Noise Spectral Ratio (HVNSR) method. The whole activities has beenarranged as follows: i) aquisition of approximately 800 HVNSR measurements located homogenously in the studied area; ii) elaboration of a geological and geophysical database based on boreholes data, Vs in-hole tests (cross hole, down-hole and seismic dilatometer techniques), seismic reflection investigations, geo- resistivity surveying and HVNSR measurements; iii) evaluation of the resonance frequency f 0 from HVNSR measurements; iv) reconstruction of the f 0 contour lines map; v) definition of the empirical correlation curve between the Quaternary sedimentary cover thickness ( z ) and f 0 ; vi) reconstruction of the Quaternary sedimentary cover contour lines map (Fig. 3). This study in theWestern L’Aquila Basin (WAP) reinforces the approach that a huge quantity of geological and geophysical data can be arranged in synthetic views,which can be usedas effective toolsin the seismic microzonation activities for urban planning and for the estimation of the local seismic response at the site scale. References D’Amico V., Picozzi M., Baliva F. and Albarello D.; 2008: Ambient noise measurements for preliminary site-effects characterisation in the urban area of Florence . Bull. Seismol. Soc. Am., 98 , 1373–1388. Del Monaco F., Tallini M., De Rose C. and Durante F.; 2013: HVNSR survey in historical downtown L’Aquila (central Italy): site resonance properties vs. subsoil model . Engineering Geology, 158 , 34-47. Di Giulio G., Gaudiosi I., Cara F., Milana G. and Tallini M; 2014: Shear-wave velocity profile and seismic input derived from ambient vibration array measurements: the case study of downtown L’Aquila . Geophys. J. Int., 198 , 848-866. Fig. 3 – Quaternary cover thickness (z) map in meters. GNGTS 2015 S essione 2.2 85