Posted: Dec 24, 2018 2:01 pm
The volcano caused a landslide into the sea that produced the tsunami. The fraction of island that slipped is noticeable in the following gif:
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Here is a comparison between images collected on 11 December and 22 December. We can see that a large part of the Anak Krakatau Island is missing. This is the most probable cause of the deadly tsunami, a landslide.
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