Krakatau, a small island group in the Sunda Strait between the islands of Sumatra and Java is one of the world's most famous volcanoes. It is a mostly submerged caldera with 3 outer islands belonging to the rim and a new cone, Anak Krakatau, that has been forming a new island since 1927 and remains highly active.
Krakatau exploded spectacularly in a devastating Plinian eruption 1883 that killed more than 30,000 people (mostly by the huge tsunamis triggered by the eruption). The eruption was one of the first global news events after telegraph lines had connected the different continents.
Background
The renowned volcano Krakatau (or Krakatoa) lies in the Sunda Strait between Java and Sumatra. Collapse of the ancestral Krakatau edifice, perhaps in 416 AD, formed a 7-km-wide caldera. Remnants of this ancestral volcano are preserved in Verlaten and Lang Islands; subsequently Rakata, Danan and Perbuwatan volcanoes were formed, coalescing to create the pre-1883 Krakatau Island. Caldera collapse during the catastrophic 1883 eruption destroyed Danan and Perbuwatan volcanoes, and left only a remnant of Rakata volcano.
This eruption, the 2nd largest in Indonesia during historical time, caused more than 36,000 fatalities, most as a result of devastating tsunamis that swept the adjacent coastlines of Sumatra and Java. Pyroclastic surges traveled 40 km across the Sunda Strait and reached the Sumatra coast.
After a quiescence of less than a half century, the post-collapse cone of Anak Krakatau (Child of Krakatau) was constructed within the 1883 caldera at a point between the former cones of Danan and Perbuwatan. Anak Krakatau has been the site of frequent eruptions since 1927.
Source: GVP, Smithsonian Institution
Source: GVP, Smithsonian Institution
Anak Krakatau volcano (Indonesia): intermittent explosive activity during March 2013
Monday Apr 01, 2013 12:05 PM | BY: T
Explosion from Krakatau on 28 March 2013 (Photo: Oystein Lund Andersen)
A small eruption took place at the volcano from 11th-12th March. The eruption produced Andesite volcanic bombs which littered the old crater rim and produced impact craters.
During a brief visit to the volcano from 22nd – 24th March, a small steam plume (emitted from two vents in the crater) was seen rising 300 – 400 M above the crater. Glow from the crater was seen at night time, which was from hot gas.
On 28th March, at 08:56 (local time) an eruption started at the volcano. The eruptions originated from the northern part of the crater producing a small ash plume that rose a few hundred meters into the air and then collapsed to form a small pyroclastic flow. Another eruption was noted at 17:16; the MODVOLC showed a thermal anomaly on the volcano.
On 29th March at 12:36 (local time), another eruption took place, from the southern part of the crater; this eruption lasted for 1 hour and 11 minutes. During this eruption, a small pyroclastic flow traveled down the N flank.
Thursday Jun 27, 2013 13:10 PM | BY: T
Our group on the rim of Anak Krakatau's crater
The group of our current trekking tour on Java climbed the summit of Anak Krakatau on 24 June. Climbing there was very difficult, because of many hot fumarolic spots and strong degassing. The summit of Anak Krakatau is now higher than before the Sep 2012 eruption. One active vent was remaining in the west part.
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