Tofua

Tofua Caldera

Tofua Island (lower left) and neighboring Kao Island, Tonga, Pacific Ocean
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°W / -19.75000; -175.07500Coordinates: 19°45′00″S 175°04′30″W / 19.75000°S 175.07500°W / -19.75000; -175.07500
Geography
Tofua Caldera

Tonga Islands, Tonga

Geology
Mountain type Volcanic caldera
Last eruption 2004 to 2013
Tofua Caldera

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.[1]

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.

Population

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].

History

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.

At Tofua (Bligh spelled it Tofoa), Bligh and eighteen loyalists sought refuge in a cave to augment their meager provisions. In the March 1968 issue of the National Geographic Magazine, Luis Marden claimed to have found this cave and the grave of John Norton. Both findings were later disproved by Bengt Danielsson (who had been a member of the 1947 Kon-Tiki expedition) in the June 1985 issue of the Pacific Islands Monthly. Danielsson identified Bligh's cave as lying on the sheltered northwest coast, where Bligh identified it; Marden's cave lies on the exposed southeast coast. Additionally, Danielsson thought it highly unlikely that the Tofuans would have allotted any grave site to Norton, or that the grave, if allotted, would have been preserved for two centuries.

In May 1943, a lifeboat containing 23 survivors from the Liberty ship SS Phoebe A. Hearst, which sank after having been torpedoed by the Japanese submarine I19 on April 30, 1943, landed. The crew survived on shellfish and coconuts until spotted by a Lockheed Hudson patrol aircraft of the Royal New Zealand Air Force and were picked up the following day by the YMS-1 class minesweeper YMS-89 of the US Navy and taken to Tongatapu.

In the early 1970s a group of eight Tongan fishermen were shipwrecked on Ata island and then survived for 18 months before being rescued by an Australian millionaire who, upon visiting the island out of curiosity, came upon the naked bearded men when scanning the island's coast through his binoculars. It took the men eight months to create fire and the flame was maintained through wind, rain and gale for the subsequent 10 months with each taking shifts to protect it. Before making fire they lived primarily on coconuts and raw seafood. After being documented by ABC news in America the story faded away; many of the men involved live on Lifuka island.

The oral tradition of Kao and Tofua

E. W. Gifford, recording Tongan myths and tales in the 1920s, documented this explanation for Tofua's caldera and the creation of Kao Island to the north:

"Three deities from Samoa, Tuvuvata, Sisi, and Faingaa, conspired to steal Tofua. So they came and tore up the high mountain by its very roots and its place was taken by a large lake. This enraged the Tongan gods very much and one of them, Tafakula, essayed to stop the thieves. He stood on the island of Luahako and bent over so as to show his anus. It shone so brilliantly that the Samoan deities were struck with fear, thinking that the sun was rising and that their dastardly works was about to be revealed. Hence, they dropped the mountain and fled to Samoa. The mountain became the island of Kao."[2]

See also

References

  1. ↑ "Tofua". Global Volcanism Program. Smithsonian Institution.
  2. ↑ Edward Winslow Gifford, Tongan myths and tales, 1924 Honolulu: Bernice P. Bishop Museum Bulletin, No. 8
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