Lithospheric structure of the southern Amazonian Craton from multiple-frequency seismic tomography: Preliminary insights on tectonic and metallogenic implications

Abstract We present a P-wave structure for the sub-continental lithospheric mantle (SCLM) beneath the southern segment of the Amazonian Craton (Central Brazil Shield – CBS) using multiple-frequency tomography. Our model includes 469 seismic events recorded between 2009 and 2017 through 314 seismic stations distributed over South America. From these events, we obtained 20507 P and 12329 PKIKP cross-correlation delays in six frequency bands centered at 0.03, 0.06, 0.13, 0.25, 0.5 and 1 Hz. Despite the limited and heterogeneous resolution throughout the CBS, because of the difficulty in the installation of seismographic stations in areas of dense coverage of tropical forest, our tests show reasonable resolution for lithospheric domains with dimensions greater than 390 × 390 km in most of the study area. We recognized a good correlation between the P-wave anomalies and the tectonic domains defined previously based on geochronology and geological data. The surface projection of these anomalies and their margins are associated with clusters of important Au, Cu–Au and IOCG deposits, as well as diamond-bearing kimberlite intrusions, allowing relating deep structures with shallow features and showing a province-scale control in the distribution of mineral deposits and occurrences in the southern Amazonian craton.