Pitch Lake
Interesting facts
- Holes dug into the lake slowly fill again as the asphalt creeps back, so the traces of a day's excavation all but vanish within about two days.
- In 2014 scientists reported that tiny water droplets of just one to three microlitres, trapped in the lake's oil, hold active microbial communities that digest the surrounding hydrocarbons.
- Microbes living in the asphalt have been counted at roughly one to ten million cells per gram.
- In 1887 Amzi Barber secured a 42-year monopoly concession over the lake from the British colonial government.
- Kerosene was distilled from the lake's pitch between 1860 and 1865, and the first wells were drilled into its oil seeps in 1866.
- Trinidad's first commercial oil well was drilled in 1903 at the western end of the Pitch Lake.
- Rainwater pools in the cracks of the asphalt are home to small fish that feed on mosquito larvae and algae.
- Geologists describe the lake as an unusual form of sedimentary volcanism, cutting across Miocene and Pliocene rock layers above a complex thrust structure.
- It is one of only a handful of natural asphalt lakes on Earth, alongside the La Brea Tar Pits in Los Angeles and Lake Guanoco in Venezuela.
Why it is worth it
In southwest Trinidad, near the village of La Brea, lies a "lake" that can be walked across: a hundred-acre sheet of grey, wrinkled asphalt, cracked into plates, with rainwater pooling in its folds. The Pitch Lake is the largest natural deposit of asphalt in the world. It covers about 40 hectares, is reported to be some 75 metres deep, and is estimated to hold around ten million tonnes of bitumen.
Its origin lies deep underground. The lake is thought to sit where two faults intersect, linked to the subduction zone under the Caribbean Plate, allowing oil from a deep reservoir to be pushed to the surface. Under the tropical sun the lighter components evaporate, leaving the heavy asphalt behind, mixed with clay. The asphalt is far from lifeless: researchers have found active communities of bacteria and archaea in it, including previously unknown species, and fungi able to live on asphaltenes alone; their activity releases bubbles of methane, carbon dioxide and hydrogen sulphide.
Walter Raleigh came here in 1595 on his expedition in search of El Dorado and used the pitch to caulk his ship, praising it as better than the pitch of Norway because it did not melt in the sun. He had been told of the lake by the local Amerindians, who had their own account of its origin. According to their legend, a village celebrating a victory over its enemies killed and ate the sacred hummingbirds, believed to carry the souls of their ancestors; in punishment the winged god opened the earth and the pitch swallowed the village. Amerindian artefacts and a human skull have indeed been found preserved in the pitch. In the 1840s Abraham Gesner first distilled kerosene from a sample of the lake's bitumen, and from 1887 the American Amzi Barber, "the Asphalt King", held a concession to the lake: much of its asphalt went to pave the first asphalt streets of New York and Washington. The lake is still mined today.
Getting there
The lake lies at La Brea in the Siparia region, about 9 km from the town of Point Fortin, reached by road from San Fernando. Piarco International Airport (POS), east of Port of Spain, is about 51 km away in a straight line.
On these lists
From the encyclopaedia
The Pitch Lake is the largest natural deposit of bitumen in the world, estimated to contain 10 million tons. It is located in Trinidad and Tobago, more specifically in La Brea in southwest Trinidad, within the Siparia Regional Corporation. The lake covers about 0.405 square kilometres and is reported to be 76.2 metres deep.
Wikipedia · CC BY-SA 4.0
10.23250, -61.62806per Wikidata