Active faulting in the Beagle Channel (Tierra del Fuego)

BRAN, M.; PALMA, F.I.; MENICHETTI, M.M.; LODOLO, E.; BUNICONTRO, S.; LOZANO, J.G.; BARADELLO, L.; WINOCUR, D.; GROSSI, M.; TASSONE, A.A.

TERRA NOVA (PRINT)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2023

0954-4879

In southern Tierra del Fuego, a significant part of the relative motion between the South America and Scotia plates is accommodated along the Magallanes-Fagnano Fault System (MFFS). However, whether some of the deformation is partitioned to the south, along the Beagle Channel Fault System (BCFS) remains unclear. In this paper, high-resolution seismic reflection profiles were used to identify fault-related ruptures in the submerged quaternary sediments of the Beagle Channel. The correlation with outcrop data and faults mapped onshore, indicates the post-glacial reactivation of two structures: (i) strike-slip faulting distributed along the E-W striking BCFS; (ii) normal offsets associated with NW-SE-trending Lapataia Fault Zone. Many of the faults reach the seafloor, affecting marine sediments, indicating they are Holocene in age. These results suggest that deformation along this segment of the transform boundary involves a wider zone than previously thought and highlight the need for a thorough hazard assessment of the area.