Complex hazard cascade culminating in the Anak Krakatau sector collapse

Thomas R. Walter, Mahmud Haghshenas Haghighi, Felix M. Schneider, Diego Coppola, Mahdi Motagh, Joachim Saul, Andrey Babeyko, Torsten Dahm, Valentin R. Troll, Frederik Tilmann, Sebastian Heimann, Sébastien Valade (+6 others)
2019 Nature Communications  
Flank instability and sector collapses, which pose major threats, are common on volcanic islands. On 22 Dec 2018, a sector collapse event occurred at Anak Krakatau volcano in the Sunda Strait, triggering a deadly tsunami. Here we use multiparametric ground-based and space-borne data to show that prior to its collapse, the volcano exhibited an elevated state of activity, including precursory thermal anomalies, an increase in the island's surface area, and a gradual seaward motion of its
more » ... ern flank on a dipping décollement. Two minutes after a small earthquake, seismic signals characterize the collapse of the volcano's flank at 13:55 UTC. This sector collapse decapitated the cone-shaped edifice and triggered a tsunami that caused 430 fatalities. We discuss the nature of the precursor processes underpinning the collapse that culminated in a complex hazard cascade with important implications for the early detection of potential flank instability at other volcanoes.
doi:10.1038/s41467-019-12284-5 pmid:31575866 pmcid:PMC6773710 fatcat:e5x4vhcnszefpkpefdmgoo4asa