Boiling Lake
| Boiling Lake | |
|---|---|
 |
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| Location | Morne Trois Pitons National Park |
| Coordinates | 15°19′06″N 61°17′39″W / 15.31833°N 61.29417°WCoordinates: 15°19′06″N 61°17′39″W / 15.31833°N 61.29417°W |
| Type | flooded fumarole |
| Basin countries | Dominica |
| Max. length | c. 60 m (200 ft) |
| Max. width | c. 60 m (200 ft) |
| Surface elevation | 800 m (2,600 ft) |
Dominica's Boiling Lake is situated in the Morne Trois Pitons National Park, Dominica's World Heritage site. It is a flooded fumarole 6.5 miles (10.5 km) east of Roseau, Dominica. It is filled with bubbling greyish-blue water that is usually enveloped in a cloud of vapour. The lake is approximately 200 feet (61 m) to 250 feet (76 m) across. The first recorded sighting of the lake was in 1870 by Edmund Watt and Henry Alfred Alford Nicholls, two Englishmen working in Dominica at that time. In 1875, Henry Prestoe, a government botanist, and Nicholls were commissioned to investigate this natural phenomenon. They measured the water temperature and found it to range from 180 to 197 °F (82–92 °C) along the edges, but could not measure the temperature at the centre where the lake is actively boiling. They recorded the depth to be greater than 195 feet (59 m).
Periodically, there have been fluctuations in the level and activity of the lake. In the 1870s it was deep; after a phreatic eruption nearby in 1880, the lake disappeared and formed a fountain of hot water and steam. Another phreatic eruption lowered the lake level by some 33 feet (10 m) from December 2004 to April 2005; later the lake level rose again, refilling the lake in just one day. The rapid draining and refilling of the lake implies that it is suspended above the local water table. A continuous flux of steam or gas generated by an underlying magmatic intrusion drives water up into the lake. A disturbance to the supply of gas can cause the lake to drain through the porous connection that normally allows steam to rise and heat the lake.
The lake rests at the bottom of a large sinkhole-like basin. More accurately, it is a flooded fumarole, an opening, crack or hole, in the Earth's crust, generally located within the vicinity of a volcano, which emits steam and gases escaping from molten lava below. Currently, the lake is viewable from a broad, cliff-top ledge about 100 feet (30 m) directly above its shore. High rock walls surround and create the basin.
The lake's grayish-blue water is easily viewed in its perpetual rolling-boil state which looks like a giant pot of water cooking and steaming on a stove. The basin's water is replenished by rainfall and two small streams which drain into the area. The water then seeps down to the lava and is heated to the boiling point. The trail leads through another volcanic area called the Valley of Desolation. The air around the area is hot, steamy and moist, supported by the sharp, acrid smell of sulphur. The area is known to have been filled with vapors and gases that escapes bubbling and escaping from boiling sulphur-water pots, small spraying and hissing geysers, cracks and holes, and a small stream that runs through and beneath the terrain. Tiny invisible sprays of steam will easily burn an ankle or foot.
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Wikipedia