2018/12/13 by Manuel Abad, Tatiana Izquierdo, Miguel Cáceres +2 · 1 voice · 3 citations
Earth and Planetary Sciences · Environmental Science · #earthquake and tectonic studies #Landslides and related hazards #Geology and Paleoclimatology Research
paper · doi:10.1111/sed.12570
openalex publication_date 2018/12/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/07
Abstract A Late Holocene cliff‐top deposit of large boulders well above the limits of modern storm waves is described from the southern coast of the Atacama Desert (northern Chile). The largest moved boulder weighs >40 t and field data point to a flood height >18·5 m above high tide level and an inland penetration greater than 284 m from the cliff edge. The minimum flow velocity needed for particle entrainment was estimated as 10·1 ms −1 and the most likely processes of sediment deposition for different boulders were deduced. The boulder distribution, sorting and orientation of imbricated debris, together with the significant wave height of extreme storms reported and the occurrence of interplate earthquakes in the study area indicate that the deposit records a single event, interpreted here as a tsunami wave train rather than exceptional storm waves. The boulder field was dated to between the 13th and the 16th Centuries ce and possibly correlates with the 1420 Oei orphan tsunami, that affected the eastern coast of Japan. A magnitude of 8·8 to 9·4 has been estimated for the earthquake, which may be one of the larger events of a super‐cycle of earthquakes in the southern Atacama Desert. These cycle‐ending earthquakes involve large rupture areas (lengths in excess of 600 km) and highly destructive ocean‐wide tsunamigenic events.