'Galunggung' , 'Galoen-gong', or 'Gunung Galunggung' is an active
stratovolcano on
Java,
Indonesia.
Hazardous eruption of 1982
''Main article:
British Airways Flight 9.''
The last major
eruption on Galunggung was in
1982, which had a
Volcanic Explosivity Index of 4 and killed 68 people. This eruption also brought the dangers of
volcanic ash to aviation to worldwide attention, after two
Boeing 747 passenger jets flying downwind of the eruption suffered temporary engine failures and damage to exterior surfaces, both planes being forced to make emergency landings at
Jakarta.
One, a
British Airways aircraft carrying 240 passengers, accidentally entered the ash cloud during night time in June
1982 150 km downwind of the volcano. All four engines failed and the aircraft descended for 16 minutes, losing 7500 metres of its 11500 metre altitude, until the crew managed to restart the engines
The following month a
Singapore Airlines aeroplane with 230 passengers aboard also inadvertently entered the cloud at night time, and three of its four engines stopped. The crew succeeded in restarting one of the engines after descending 2400 metres. Both aircraft suffered serious damage to their engines and exterior surfaces
[1].
Avalanche deposits
A hummocky deposit known as the Ten Thousand Hills of
Tasikmalaya attracted the attention of early
20th century geologists. Houses were built on the hummocks since they provided good defence against hostile people, and being above the paddy fields were free of
mosquitoes and
rats.
Originally, it was thought that either it had been formed by a
lahar caused by the release of the waters of the
crater lake, or that it was man-made;
composed of rocks and boulders dumped there after being cleared from
paddy fields.
However, in the light of the
Mount St. Helens eruption of
1980 and from examination of the
Mount Shasta deposits it has become clear that the hummocks are a debris-avalanche deposit. Like these mountains, Galunggung has a
horseshoe-shaped crater indicating a massive landslide, and examination of shattered
lava blocks revealed them to be similar to deposits on the other two volcanoes. According to
radiocarbon dating of samples taken from a
lava flow the landslide happened within the last 23,000 years.
See also
★
Volcanoes of Java
★
List of volcanoes in Indonesia
Notes and references
1. Encyclopedia of Volcanoes, , , , Academic Press, 2000, ISBN 0-12-643140-X
★
Volcanic Debris Avalanches, S. Brantley & H. Glicken, , , Earthquakes & Volcanoes, 1986
External links
★
NOAA facts and figures about Galunggung
★
Volcanological Survey of Indonesia
★
Official website of Indonesian volcanoes at USGS