<P> A numerical model for a Krakatoa hydrovolcanic explosion and the resulting tsunami was described by (Mader & Gittings, 2006). A high wall of water is formed that is initially higher than 100 meters driven by the shocked water, basalt and air . </P> <P> Although the violent phase of the 1883 eruption was over by late afternoon of 27 August, after light returned by the 29 August, reports continued for months that Krakatoa was still in eruption . One of the earliest duties of Verbeek's committee was to determine if this was true and also verify reports of other volcanoes erupting on Java and Sumatra . In general, these were found to be false, and Verbeek discounted any claims of Krakatoa still erupting after mid-October as due to steaming of hot material, landslides due to heavy monsoon rains that season, and "hallucinations due to electrical activity" seen from a distance . </P> <P> No signs of further activity were seen until 1913, when an eruption was reported . Investigation could find no evidence the volcano was awakening, and it was determined that what had been mistaken for renewed activity had actually been a major landslide (possibly the one which formed the second arc to Rakata's cliff). </P> <P> Examinations after 1930 of bathymetric charts made in 1919 show evidence of a bulge indicative of magma near the surface at the site that became Anak Krakatau . </P>

The​ submarine which was more than 100 m​ long was found several km off shore