Report on Krakatau (Indonesia) — February 1988
Scientific Event Alert Network Bulletin, vol. 13, no. 2 (February 1988)
Managing Editor: Lindsay McClelland.
Krakatau (Indonesia) Ash emission; glow; felt earthquakes
Please cite this report as:
Global Volcanism Program, 1988. Report on Krakatau (Indonesia). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 13:2. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198802-262000.
6.102°S, 105.423°E; summit elev. 813 m
All times are local (unless otherwise noted)
An increase in the volume of white fume from the summit crater was observed beginning 11 February. Similar activity, stronger than it had been for several years, continued intermittently until 28 February, when plume color darkened and emissions became more frequent. Plumes apparently rose a few hundred meters above the crater. On 1 March, glow was visible from the Java coast, . . . suggesting the presence of new lava. Earthquakes were felt 5-6 March from Anyer, 55 km E of the volcano.
Geologic Background. The renowned volcano Krakatau (frequently misstated as Krakatoa) lies in the Sunda Strait between Java and Sumatra. Collapse of the ancestral Krakatau edifice, perhaps in 416 or 535 CE, 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, and left only a remnant of Rakata. 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.
Information Contacts: VSI; A. Ritter, Carita Beach Hotel, Java.