The crustal structure of the Iberian Central System has been studied using passive seismic techniques. We have applied seismic interferometry to a passive dataset through two techniques to generate a lithospheric-scale cross-section of the orogen. The resulting images constrain the structure of the crust below the mountain range and that of its surrounding sedimentary basins. Both techniques provide complementary results. The resulting images reveal that the crust¿mantle boundary is relatively flat, with arrival times of approximately 10 s two-way travel time except in the Central System, where reflectors are located at 12 s two-way travel time. This indicates a clear thickening of the crust below the core of the orogen, resulting, most probably, from an imbrication of the crust. The boundary between the upper and lower crust is found at 5 s two-way travel and it is also slightly deeper below the mountain range.

This research has been supported by the Spanish National Research Program (grant nos. CGL2014 56548-P and CGL2016-81964-REDE), the regional government of Castilla and León (project SA065P17), and the Generalitat de Catalunya (grant no. 2017-SGR-1022);Juvenal Andrés is supported by FPI from the Spanish Ministry of Science, Innovation and Universities (grant no.BES-2015-071683).

X Congreso Geológico de España, 5-7 Julio 2021, Vitoria - Gasteiz