Erupting Volcano Anak Krakatau (APOD 2009 July 13)
Posted: Mon Jul 13, 2009 5:38 am
http://apod.nasa.gov/apod/ap090713.html
http://en.wikipedia.org/wiki/Krakatoa wrote:
<<Before the 1883 eruption, Krakatoa comprised three main islands: Lang ("long", now called Rakata Kecil or Panjang) and Verlaten ("forsaken" or "deserted", now Sertung), which were edge remnants of a previous very large caldera-forming eruption; and Krakatoa itself, an island 9 km (5.6 mi) long by 5 km (3.1 mi) wide. Also there was a tree-covered islet near Lang named Poolsche Hoed ("Polish hat", apparently because it looked like one from the sea) and several small rocks or banks between Krakatoa and Verlaten. There were three volcanic cones on Krakatoa: Rakata, (820 m/2,700 ft) to the south; Danan, (450 m/1,500 ft) to the north; and Perboewatan, (120 m/390 ft) to the north (Danan may have been a twin volcano).
http://earthobservatory.nasa.gov/IOTD/view.php?id=3844
Verbeek, in his report on the eruption, predicted that any new activity would manifest itself in the region which had been between Perboewatan and Danan. This prediction came true on 29 December 1927, when evidence of a submarine eruption was seen in this area (an earlier event in the same area had been reported in June 1927). A few days later, a new island volcano, named Anak Krakatau ("Child of Krakatoa"), broke water. Initially, the eruptions were of pumice and ash, and it (and two later islands) was quickly eroded away by the sea; but eventually Anak Krakatau #4 (broke water in August 1930) produced lava flows faster than the waves could erode them. Of considerable interest to volcanologists, this has been the subject of extensive study.
Since the 1950s, Anak Krakatau has grown at an average rate of five inches (13 cm) per week. The island is still active, with its most recent eruptive episode having begun in 1994. Since then, quiet periods of a few days have alternated with almost continuous Strombolian eruptions, with occasional much larger explosions. The most recent eruption began in April 2008, when hot gases, rocks, and lava were released. Scientists monitoring the volcano have warned people to stay out of a 3 km zone around the island.
http://earthobservatory.nasa.gov/IOTD/view.php?id=5638
There are two generally accepted modern spellings, Krakatau and Krakatoa, although it must be mentioned that Krakatau is frequently misstated as Krakatoa and Krakatau is the only official name. This is most likely caused by a British journalist (the result of a typographical error: the journalist swapped the 'a' and 'o' of the Portuguese spelling) who reported on the massive eruption of 1883. Also, like Egypt a couple of decades earlier, Polynesia (South Pacific) was in vogue in the late 19th century, and the Polynesian-like suffix -oa (as in Samoa) may have caught on as a result. While Krakatoa is more common in the English-speaking world, the Indonesian Krakatau tends to be favored by others, including geologists. Verbeek seems to have started the modern convention of using Krakatau for the island proper and reserving Rakata for the main cone.>>