The proper name for a “tar pit” is “natural asphalt lake,” and there are only five of them in the world. One can be found at Carpinteria State Beach.
Smaller and less well-known than its cousin the La Brea Tar Pits in Los Angeles, the Carpinteria version is nonetheless the eldest of the two, dating back 2.6 million years to the Pleistocene Age.
The Carpinteria Tar Pits take us back to a time when extinct but exotic species like giant sloths, saber-toothed tigers, dire wolves and tusked mastodons roamed Earth and the Central Coast. The Chumash, believed to have arrived here 13,000 years ago, would have lived alongside these long-vanished animals.
A strong smell of tar greets the visitor on the cove-like beach where the tar pits lie. There is a fine view of the Channel Islands from here, and low tide reveals interestingly-shaped driftwood scattered about, as well as rocks made smooth by the endless back and forth of the waves washing over them. At the far end of the cove sits a pier owned by Chevron.
But it is the tar pits we came to see. Formed from petroleum seep, as bitumen, or natural asphalt, comes in from the Carpinteria offshore oil field then pushes its way up from below ground and finds a fissure to come through. How this phenomenon works is easy to see on the faces of the cliffs that line the beach — the bitumen, emerging from a crack in the rock, then flows downward, covering the rock like thick black ink and stopping just short of the sand.
In another spot is a pond-like expanse of tar at ground level that stretches all the way out to the water. Here, in the distant past, unfortunate animals blundered in and were stuck, condemned to die in the sticky black mass so that in the future their fossilized remains could provide a window into Earth’s ancient history.
An incredible 1 million fossils have been recovered from tar pits worldwide. Approximately 90 percent of these are of predators that likely ventured into the tar pits in pursuit of prey already stuck in the tar.
The tar pits also reveal prehistoric wood, vegetation, insects, birds, vertebrates and invertebrates. At the La Brea tarpits in 1914 the body of a woman was found. She died approximately 10,000 years ago, perhaps the victim of a ritual sacrifice, because a domestic dog was at her side.
The world’s largest tar pit is found in Trinidad and Tobago. Pitch Lake contains 10 million tons of bitumen and is 250 feet deep. The others are the La Brea Tar Pits in Los Angeles, Lake Bermudez in Venezuela, and the McKittrick Tar Pits in California’s Kern County.
The Carpinteria Tar Pits were first seen by Europeans on Aug. 17, 1769, when the Portola expedition reached the area. Noting that the Chumash were busily building their ocean-going canoes here, called tomols, and making them waterproof by using tar they had mined from the pits, the Spaniards named the area “Carpinteria,” Spanish for “Carpenter’s Shop.” Early in the 20th century asphalt from the Carpinteria pits was used to help build Pacific Coast Highway. Later the tar pits became part of Carpinteria State Beach and were opened to the public in 1941.
You can get to the Carpinteria Tar Pits by taking Concha Loma Avenue from Carpinteria Avenue, then getting on Calle Ocho and following it to the end. Walk across the railroad tracks, and the beach and the tar pits are straight ahead.