TY  - JOUR
A1  - Jara-Muñoz, Julius
A1  - Melnick, Daniel
A1  - Li, Shaoyang
A1  - Socquet, Anne
A1  - Cortés-Aranda, Joaquín
A1  - Brill, Dominik
A1  - Strecker, Manfred
T1  - The cryptic seismic potential of the Pichilemu blind fault in Chile revealed by off-fault geomorphology
JF  - Nature Communications
N2  - The first step towards assessing hazards in seismically active regions involves mapping capable faults and estimating their recurrence times. While the mapping of active faults is commonly based on distinct geologic and geomorphic features evident at the surface, mapping blind seismogenic faults is complicated by the absence of on-fault diagnostic features. Here we investigated the Pichilemu Fault in coastal Chile, unknown until it generated a Mw 7.0 earthquake in 2010. The lack of evident surface faulting suggests activity along a partly-hidden blind fault. We used off-fault deformed marine terraces to estimate a fault-slip rate of 0.52 ± 0.04 m/ka, which, when integrated with satellite geodesy suggests a 2.12 ± 0.2 ka recurrence time for Mw~7.0 normal-faulting earthquakes. We propose that extension in the Pichilemu region is associated with stress changes during megathrust earthquakes and accommodated by sporadic slip during upper-plate earthquakes, which has implications for assessing the seismic potential of cryptic faults along convergent margins and elsewhere.
Y1  - 2022
U6  - https://doi.org/10.1038/s41467-022-30754-1
SN  - 2041-1723
VL  - 13
PB  - Springer Nature
CY  - London
ER  -