I am standing on a large mineral bed. Is it a glorified seep or an environmental disaster? The view on our arrival early one Saturday seems less than auspicious. On the far flank, there seems to be some industry — warehouses, pipes and hoppers — but all is quiet today. Mindful of the advice to avoid hustlers who might take advantage of our zeal to visit at all costs, Shazam and I had waited at the small car park until we saw a guide appropriately attired in an official red tee shirt and Cyrill Billy assigned himself to walk out with us.
Of course, so as to justify his appointment, we are shown a faded photograph of an oil-covered man, zombie-like after rescue from the tar and presumed guilty of straying unsupervised from the route.
The three of us walked through the curtain of sedge and out on to the tar field, Cyrill Billy recounting his well-rehearsed patter while prodding the ground with an umbrella. It is like soft tar. Indeed, it is soft tar. But it does not move or rebound and nor does it clag to your shoes. There is no particular odor; nor does it flow except in a few places where the surface skin is split, causing the gentle exuding of a rich black fudge.
None can resist poking and probing at the wound and pulling the tar into extended tendrils of thick, viscous grease. There is a network of fissures that are mostly filled with water, and I am surprised to see the water is clear, with no slick, revealing schools of small fish suspended among a desultory fizz of bubbles.
The largest tar pit in the world awaits approval as a Unesco World Heritage Site in its quiet unassuming corner of Trinidad while it lays bare the oil history of this land. The magic is in that history: the industry it founded and the unseen thermoplastic properties of this mineral bed. A mine that refills every night; now that really is magic.
Despite the economic interest and obvious focus for study, I am a bit unconvinced by the explanation for the pitch lake. It covers an impressive acres or so 40 hectares and is up to feet 75m deep, classically portrayed as a bowl shape. I have seen a cross-section, a detached figure I presume comes from an early 20th-century document, which appears to depict where the lake had been penetrated and records its reduction in size between and It is probably a breached oil field, now revealed as a massive seep, any light gassy fraction naturally venting away to leave a slow churn of biodegraded bitumen that appears to replenish over time.
The proximity and intersection of two large faults is cited as facilitating the up flow, an association with faulting it may have in common with other well-known tar pits, including the identically named deposits in the suburbs of Los Angeles, which lie above the Salt Lake oil field and the 6 th Street fault. Prevosti, M.
Alberdi, and C. Woodburne L. Albright, III, ed. Museum of Northern Arizona Bulletin Tar Pits of the World. After trekking through the jungle for an hour we came across this 'wild' tar pit. It's a great place to study how wildlife today act around this natural phenomenon. Tar Pits of the World Asphaltic deposits or "tar pits" present a unique opportunity to study past ecosystems because they preserve many different kinds of fossils and lots of them!
Zoom in and click on the map icons to learn about fossiliferous tar pits around the world! Welcome to the B. Trinidad and Tobago. DeMay, I. Pleistocene bird life of the Carpinteria asphalt, California.
Carnegie Institution of Washington Publication, , Miller, L. Pleistocene birds from the Carpinteria asphalt of California. Louderback, R. Williams Eds. Berkeley: University of California Press. Two Pleistocene avifaunas from the Carpinteria asphalt. Geological Society of America Bulletin, 43, Shaw, C. La Brea and beyond: The paleontology of asphalt-preserved biotas, ed.
JM Harris. Iturralde-Vinent M. Caribbean Journal of Science, Steadman D. Asynchronous extinction of late Quaternary sloths on continents and islands. PNAS, Hoffstetter, R. Memoires de la Societe Geologique de France, n. Sobre los Megatheriidae del Pleistoceno del Ecuador, Schaubia, gen. Lemon, R. Pleistocene geology and paleontology of the Talara region, northwest Peru. American Journal of Science — Lindsey E.
Tanque Loma. A new late-Pleistocene megafaunal tar seep locality from southwest Ecuador. Journal of South American Earth Sciences, Quaternary bird life of the McKittrick asphalt, California. An interesting feature of the La Brea Tar Pits is the discovery of fossils from prehistoric species trapped in the asphalt. Over a period of centuries, the bones of these animals were preserved in the tar. A nearby museum preserves the fossils of these pre-historic species, including a saber-tooth cat, giant ground sloths, dire wolves, and turtles.
Occupying an area of about hectares, it is bigger than the Pitch Lake by area but smaller in terms of volume. The depth of Lake Bermudez varies between 4. The asphalt from the lake has long been used by local indigenous populations, such as the Warao people who used it to waterproof canoes.
Commercial mining of asphalt from the lake by a US company later occurred with permission from the Venezuelan government.
The mining began in , but soon created controversy and internal conflict within the country. Asphalt mining in the lake was stopped in and has not been resumed. The existence of the tar pits has long been known by the indigenous populations, and the asphalt was used by locals for trade, decoration, and waterproofing. Commercial asphalt mining in the area started in the s. The tar pits have also yielded significant paleontological information, since they preserved the bones of hundreds of animals from the Pleistocene Age.
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