Bathymetry and Shallow Seismic Imaging of the 2018 Flank Collapse of Anak Krakatau

The flank failure and collapse of Anak Krakatau on December 22nd, 2018 triggered a destructive tsunami. Whether the prior activity volcano led to this collapse, or it was by another means, remains challenge understand. This study seeks investigate recent submarine mass-landslide deposit emplacement processes, including seafloor morphology landslide extent. Bathymetry sparker seismic data were used during study. collected in August, 2019 shows run-out area morphology. acquired May, 2017, is as base limit estimate volume collapse. Comparisons between 2017 provide an insight into sequence, structure below seafloor. From these results we highlight two areas submarine-mass deposit, one proximal island (?1.6 km) distal (?1.4 km). resulting analysis suggests that might be produced frontally compressional, faulted, landslide, critical stability slope, due volcanic activity. Blocky seabed features clearly lie southwest Krakatau, may represent blocks landslide. reveals blocky facies extends ?1.62 km width around block thicknesses vary up 70.4 m. marine provides new run out extent, together with are not available from satellite imagery subaerial surveys. We conclude ?7.02 ± 0.21 2 .