August 3 – Anniversary of the "Discovery" of the La Brea Tar Pits

nPostednon August 3, 2014

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nLovelyngreen grass… a boulder here or there, half submerged in thenearth… a patch of weeds over here, a patch of bare dirt over there,na patch of—

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nWait!!nWhat is THAT?

nIt’snblack. It’s sticky–yicky, oozy–squoozy. It’s even bubbly!

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nIt’sntar!

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nMynsister used to live just a block away from the La Brea Tar Pits, innLos Angeles, California. And not all of the tar is safely fenced offnfrom us modern humans walking around Hancock Park. As we walkednalong, we often saw sticky patches of fresh tar bubbling up here andnthere!

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nItnwas quite…unnerving!

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nYounknow that there is petroleum, or oil, underneath the ground in somenplaces, right? Well, that is the case in some areas of Los Angeles.nSome crude oil has been seeping up to the Earth’s surface throughncracks in the crust; once exposed to the air and sun, some of thenlighter components of the oil has been evaporating away. The densernpart that is left behind is called natural asphalt, or tar.

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nThenpools of tar have been growing (and sometimes shrinking) over tens ofnthousands of years. And over the years, the pools have beennaccumulating a dusting of dust and dirt and a partially covering ofnleaves and other natural debris. And over those thousands of years,nmany animals have stumbled into the pits, where they found themselvesnstuck. Naturally, some predators that saw the stuck animals decidednto get an easy dinner—but then they also got stuck!

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nOnnthis date in 1769, a Spanish friar named Juan Crespi noticed andnwrote about the pools of tar—and he is the first person we know sawnthem. (Obviously, many native Americans must have seen the tar poolsnat one point or another—but we don’t have records that tell us whonor when. That is why Crespi gets the label “discoverer,” whennreally he was probably the first European person—not the firstnperson—to discover the tar pools!)

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nDidnyou know…?

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nLan Brea means “the tar” inn Spanish. So the name The La Brea Tar Pits translates to “The Then Tar Tar Pits.”

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nThen tar not only killed a lot of animals, it preserved their bones asn fossils. At the La Brea Tar Pits there is a museum in which many ofn the more than 1,000,000 fossils found in the pits are displayed. Then species found include more than 150 species (kinds) of plants andn more than 460 species of animals.

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Onlyn one human skeleton has ever been found in the La Brea Tar Pits—an woman who lived and died around ten thousand years ago. There isn evidence that suggests that she was deliberately submerged in then tar pit only after she died. In other words, the tar didn’t killn her; instead, she was buried in one of the pools.

nJosen Longinos Martinez wrote in 1792: “Nearn the Pueblo de Los Angeles there are more than twenty springs ofn liquid petroleum, pitch, etc. Farther to the west of said town . . .n there is a great lake of pitch, with many pools in which bubbles orn blisters are constantly forming and exploding. They are shaped liken conical bells and, when they burst at their apex, they make a littlen report.”
(Inn this case,n report meansn an explosive sound.)

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nTheren have been more than 60 tar pits excavated by scientists, althoughn only about 12 were found to hold a lot of fossils.

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nTheren have been no dinosaur bones discovered in the tar pits. Then dinosaurs died out millions and millions of years before the poolsn of tar formed.

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