Seismic potential of the northern Chile region of the Nazca subduction zone

The northern Chile region of the Nazca subduction zone has hosted a Mw 8.5-9.0 earthquake in 1977 which induced a tsunami. The different magnitude estimates of this event are based on the evaluation of seismic intensities, tide gauge information and/or on the event’s inferred length, however, its actual along-strike extent is still under discussion. Based on geodetic data, former studies have also suggested this region awaits a Mw 8.6-8.8. In our study, we propose to revisit the evaluation of the seismic potential of the region, accounting for the fault’s moment deficit rate, earthquake magnitude-frequency distribution and earthquake physics. To do so, we combine an improved probabilistic estimate of moment deficit rate with results from dynamic models of the earthquake cycle, taking into account the influence of a potential barrier which could control the extent and therefore the magnitude of large events.