This is Where Tar Comes From

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Will McGough

Pitch Lake is located on the southwest side of Trinidad (see above photo), but a visitor will probably feel like they’re on the moon at times. Called Tierra de Brea, it is a natural deposit of asphalt, and sometimes referred to as a "tar pit." It's true—you can literally stick a stick into the ground, pull it up, and with it will come what looks like tar. Stand in one place too long, and you’ll feel your shoes begin to sink in and create an imprint.

According to most histories, Sir Walter Raleigh was shown the lake by locals when he arrived in Trinidad in search of El Dorado, the fabled city of gold. He found the tar to be great for caulking for his ships, and was credited with its discovery when he returned home with several barrels.

Trinidad's Pitch Lake is one of five of its kind. There are three others in California and one more in Venezuela. (Although there are smaller deposits of asphalt found in various locations around the world, these are the only lakes.) Pitch Lake is the biggest, measuring 246 feet deep and about 99 acres in size.

The second-largest lake, Lake Bermudez in Venezula, halted its commercial mining operations back in the 1930s, and the pit in Los Angeles is dedicated to archaeological research and the preservation of fossils. The area in Carpinteria is just south of where I used to live in Santa Barbara, and its presence is felt along the coast. I can tell you firsthand that there were many days when I walked out of the ocean near Santa Barbara and had tar on the bottom of my feet and bathing suit. And I still have the stained suits to prove it.

Ironically enough, despite having such a supply of asphalt on hand, Trinidad has some of the worst roads in the Caribbean—the country is an aggressive exporter of its product for road and runway construction in Europe and the United States. According to our guide, scientists predict that there's about a 400-year supply left underground—which really isn't that long, although I suppose it gives Trinidad plenty of time to patch up a few potholes if they so choose. Another interesting piece of trivia is that the "pitch"—another name for the tar—is where the phrase "pitch black" comes from, similar to the descriptions “red rose,” “sky blue,” and “snow white.”

There’s a picture under a hut outside of the visitor’s center that shows a man who had been in up to his waist—the pitch sucking him in like quicksand—but unfortunately they weren’t willing to let me become the second person to go that deep. (I’m weird like that.) Instead, I settled for a walking tour and a quick dip in one of the sulfur pools, making sure to leave hand and footprints in my wake. The pools are obviously bigger during the rainy summer months, but I found one deep enough to swim in during my dry-season visit in March.

Will McGough

More nerdy stuff: The pitch drop experiment in Australia is one of the longest running scientific experiments in which a “solid” piece of pitch is placed in a funnel and flows over a very long timescale. Because the viscosity of pitch is 230-billion times that of water, a droplet falls from the funnel only once every eight to 12 years. Only eight drops have fallen since the experiment was set up in 1927. In a case of very good timing, the 9th drop is expected to fall sometime this year.

Pretty cool, yeah? Now every time you turn out the lights or get in your car, you can think of Trinidad.

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April 29, 2013 - 5:00pm
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