Lake Asphalt (Pitch Lake) – the place of the natural flow of asphalt onto the surface of Earth, located on the island of Trinidad near the town of La Brea. The surface of this “lake” is 46 ha, maximum depth determined by gravimetric measurements – 106 m. Powered from shallow subsurface deposits of bitumen, is composed of a mixture of water, bitumen, and gas in the form of a semi-liquid emulsion. On the surface this mixture hardens the party, creating the hard edges of the asphalt crust.
The genesis of Lake Asphalt is not fully understood, it is assumed that the lake basin was formed due to ejections of gas and mud (mud volcano), perhaps with the participation of the earthquake. Defaulting shallowly beneath the surface of crude oil, which escapes, the process of transformation – the loss of volatile components and partially oxidize and polymerize the other, thereby forming a natural asphalt.
Lake discovered by Europeans in 1595, Sir Walter Raleigh, who used asphalt as a sealing material for the hulls of ships. In later centuries, operated on an industrial scale, since the beginning of the nineteenth century, the asphalt of the lake was used as material for road construction after the treatment is characterized by very good properties (resistance to high temperatures – above 90 ° C). It covered, among others Washington’s Pennsylvania Avenue, in which the White House.
When the English explorer Sir Walter Raleigh landed in Trinidad in the West Indies in 1595, he was the first European who heard about the Tierra de Brea or Picha, where there are large deposits of tar (bitumen or asphalt). It’s strange, but fascinating place, probably with the largest deposits of tar in the world, is now known as Lake Asphalt Trynidadzkie.
Lake occupies an area of 44 hectares and is 82 m deep. Created 50 million years ago from the decaying remains of sea creatures. As a result of this process produced hydrocarbons, which pass through permeable rocks. Later, the movement of rocks was elevated to the surface, and the sun spiekło skorkupę them so hard that you can walk on it.
Asphalt on the surface of the lake creates dark platinum, and in the hollows between them collected rainwater. The lake is in constant motion because the asphalt is moving from the center outwards. As a result of gas evolution, from time to time hear a strange gurgle.