Tofua
| Tofua Caldera | |
|---|---|
Tofua Island (lower left) and neighboring Kao Island, Tonga, Pacific Ocean
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| Highest point | |
| Elevation | 515 m (1,690 ft) |
| Prominence | 515 m (1,690 ft) |
| Listing | List of volcanoes in Tonga |
| Coordinates | 19°45′00″S 175°04′30″W / 19.75000°S 175.07500°WCoordinates: 19°45′00″S 175°04′30″W / 19.75000°S 175.07500°W |
| Geography | |
 Tofua Caldera
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| Geology | |
| Mountain type | Volcanic caldera |
| Last eruption | 2004 to 2013 |
Tofua Caldera, in Tonga, is the summit caldera of a steep-sided composite cone that forms Tofua Island. Tofua Island is in Tonga's Ha'apai island group. Pre-caldera activity is recorded by a sequence of pyroclastic deposits and lavas constituting the older cone, followed on the northern part of the island by froth lavas or welded and unwelded ignimbrite. Following the caldera collapse, lavas were erupted from the northern part of the island and the caldera-rim fissure zone, scoria and lavas from the caldera-wall fissure zones, pyroclastics and lavas from intracaldera cones, and recent pyroclastic fall deposits on the outer cone. Eruptive products are mainly basaltic andesites and andesites, plus occasional dacite flows within the older cone. A postcaldera cone with fumarolic activity (Lofia) is in the northern part of the caldera; a crater lake with 500 m (1,600 ft) depth occupies most of the remainder.
Most historical eruptions have been small explosions from Lofia cone along the northern caldera rim. The eruptions of 1958-59 caused most of the islanders to evacuate for a year or more.
Tofua is visited by fifty men from Kotu Island for 2 weeks each year. They are there primarily to grow kava (Piper methysticum) for export to Tongatapu. This gives the island an average yearly population of 2 [(50*14+0*351)/365].
The Mutiny on the Bounty (1789) took place about 30 nautical miles (56 km; 35 mi) from Tofua. Captain William Bligh navigated the overcrowded 23-foot (7 m) open launch on an epic 41-day voyage first to Tofua and then to Timor equipped only with a sextant and a pocket watch — no charts or compass. He recorded the distance as 3,618 nautical miles (6,701 km; 4,164 mi). He passed through the difficult Torres Strait along the way and landed on June 14. The only casualty of his voyage was a crewman named John Norton who was stoned to death by the natives of Tofua, the first island they tried to land on.
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Wikipedia