Seulawah Agam | |
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![]() Mount Seulawah Agam | |
Highest point | |
Elevation | 1,810 m (5,940 ft) [1] |
Prominence | 1,610 m (5,280 ft) [2] |
Listing | Ultra Ribu |
Coordinates | 05°26′51″N95°39′21″E / 5.44750°N 95.65583°E Coordinates: 05°26′51″N95°39′21″E / 5.44750°N 95.65583°E [2] |
Geography | |
Geology | |
Mountain type | Stratovolcano |
Last eruption | January 1839 |
Seulawah Agam is an extensive forested stratovolcano located at the northwestern tip of Sumatra. Several names have been given to the mountain: Seulawaih Agam, Seulawain Agam, Solawa Agam, Solawaik Agam, Selawadjanten and Goldberg. [3]
The volcano was formed during the Pleistocene-Holocene age. [1] The mountain has a large caldera, called Lam Teuba. A smaller 8×6 km caldera is within the Lam Teuba caldera. The volcano contains several hills: sedimentary hills, old volcano hills, a volcanic cone and peneplain area. The volcanic cone was formed by lava and pyroclastic flows. [3] There are three craters. The Tanah Cempago crater is easily recognized, while the other two are covered with vegetation.
As of January 2013, Seulawah Agam is showing signs of renewed activity. Localised seismicity has been recorded in the vicinity of the volcano.
A caldera is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is lost. The ground surface then collapses into the emptied or partially emptied magma chamber, leaving a large depression at the surface. Although sometimes described as a crater, the feature is actually a type of sinkhole, as it is formed through subsidence and collapse rather than an explosion or impact. Compared to the thousands of volcanic eruptions that occur each century, the formation of a caldera is a rare event, occurring only a few times per century. Only seven caldera-forming collapses are known to have occurred between 1911 and 2016. More recently, a caldera collapse occurred at Kīlauea, Hawaii in 2018.
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