Estimates of crustal thickness in central Italy from teleseismic receiver functions

Abstract

We have estimated Moho depths at 39 broadband, 3-component seismic stations installed in central Italy in an area of about 250 x 330 km2, using receiver functions computed from teleseismic events. Stations belong to the Italian Seismic Network that is operated by the Istituto Nazionale di Geofisica e Vulcanologia. In the study area we have found that Moho depth ranges from 24 to 44 km. The shallowest Moho is found along the western side of central Italy and is consistent with the thinned Tyrrhenian crustal domain. Larger crustal thickness characterizes the area of the Apennine mountain range, a Tertiary thrust-and-fold belt running from NW to SE along the whole length of the Italian peninsula. Crustal thickness of 30-32 km are estimated along the eastern margin of central Italy, where the Adriatic continental lithosphere represents the foreland of the E-verging Apennine chain. In this work we have reconstructed the Moho surface beneath central Italy after assigning each station to the different crustal domains (Tyrrhenian vs Adriatic/Apennine) on the basis of location, surface geology, available deep-well data.