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La Brea Tar Pits

Coordinates: 34°03′46″N 118°21′22″W / 34.062828°N 118.355992°W / 34.062828; -118.355992
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For the tar pit in La Brea, Trinidad and Tobago, see Pitch Lake.
The Page Museum, Hancock Park, interprets La Brea

The La Brea Tar Pits (or Rancho La Brea Tar Pits) are a famous cluster of tar pits located in Hancock Park in the urban heart of Los Angeles, California, United States. Asphalt or tar (which in Spanish is la brea, see below) has seeped up from the ground in this area for tens of thousands of years. The tar is often covered with water, which attracts wildlife. Over the centuries, the bones of animals that died in the pits sank into the tar and were preserved. The George C. Page museum is dedicated to researching the tar pits and displaying specimens from them.

Location and formation of the pits

The Tar Pits in 1910; note the oil derricks in the background

The La Brea Tar Pits and Hancock Park are situated within urban Los Angeles, California, near the Miracle Mile district.

Tar pits are composed of heavy oil fractions called asphalt, which came out of the earth as oil. In Hancock Park, asphalt seeps up from underground. The asphalt is derived from petroleum deposits that originate from underground locations throughout the Los Angeles Basin. The asphalt reaches the surface at several locations in the park, forming pools.

This seepage has been happening for tens of thousands of years. From time to time, the asphalt would form a pool deep enough to trap animals, and the surface would be covered with layers of water, dust, and leaves. Animals would wander in, become trapped and eventually die. Predators would also enter to eat the trapped animals, and themselves become stuck.

As the bones of the dead animals sink into the asphalt, it soaks into them, turning them a dark-brown or black color. Lighter fractions of petroleum evaporate from the asphalt, leaving a more solid substance, which holds the bones. Apart from the dramatic fossils of large mammals, the asphalt also preserves very small "microfossils," wood and plant remnants, insects, dust, and even pollen grains.

Radiometric dating of preserved wood and bones has given an age of 38,000 years for the oldest known material from the La Brea seeps, and they are still ensnaring organisms today.

Early History

The Portola Expedition, a group of Mexican explorers led by Gaspar de Portola, made the first written record of the tar pits in 1769. Father Juan Crespi wrote, "While crossing the basin the scouts reported having seen some geysers of tar issuing from the ground like springs; it boils up molten, and the water runs to one side and the tar to the other. The scouts reported that they had come across many of these springs and had seen large swamps of them, enough, they said, to caulk many vessels. We were not so lucky ourselves as to see these tar geysers, much though we wished it; as it was some distance out of the way we were to take, the Governor [Portola] did not want us to go past them. We christened them Los Bolcanes de Brea [the Tar Geysers]."[1]

Scientific Resource

File:Rancho La Brea Tar Pit.jpg
Models of mammoths at the La Brea Tar Pits in Hancock Park

Work on excavating the bones started[clarification needed] in the early 20th century. In the 1940s and 1950s, there was great public excitement over the dramatic mammal bones recovered. (The organic remains could be called "fossils" because they were dug up, but they are not mineralized as true fossils are.)

By the 2000s, attention had shifted to smaller specimens such as preserved insects and plant parts, including microfossils such as pollen grains. These remains help to define a picture of the Los Angeles basin during the glacial age, when the climate was cooler and moister.

Source of methane discovered

Methane gas also seeps up, causing bubbles that make the asphalt appear to boil. Asphalt and methane also appear under surrounding buildings, requiring special operations to remove, lest it weaken the buildings' foundations. In 2007, researchers from UC Riverside discovered that the bubbles are caused by hardy forms of bacteria embedded in the natural asphalt. The bacteria are eating away at the petroleum and releasing methane. Of the bacteria sampled so far, about 200 to 300 are previously unknown species.[2]

Gas bubble slowly emerging from a smaller tar pit at La Brea Tar Pits.

George C. Page Museum

The George C. Page Museum, part of the Natural History Museum of Los Angeles County, is built next to the tar pits in Hancock Park on Wilshire Boulevard. It tells the story of the tar pits and presents specimens from them. Visitors can walk around the park and see the tar pits. On the grounds of the park are life-sized models of prehistoric animals in or near the tar pits.[3] Of more than a hundred pits, only Pit 91 is still regularly worked on. The museum encloses the pit and tourists can watch as it is excavated for two months each summer. The work is done by volunteers under the watchful eyes of paleontologists.[4]

La Brea is a famous and accessible paleontological site because it is in a large city, with dramatic exhibits well presented at the Page Museum.

Excavation of newly uncovered pits announced in 2009

On February 18, 2009, George C. Page Museum formally announced the 2006 discovery of 16 fossil deposits under an old parking lot owned by the Los Angeles County Museum of Art next to the tar pits.[5] Among the finds are bones of a saber-toothed cat, six dire wolves, bison, horses, a giant ground sloth, turtles, snails, clams, millipedes, fish, gophers, and an American lion.[5][6] Also discovered is a near-intact mammoth skeleton, nicknamed Zed; the only pieces missing are a rear leg, a vertebra and the top of his skull, which was shaved off by excavation equipment.[6][7][8]

These fossils were packaged at a construction site and removed to the museum so that construction could continue. Over twenty large accumulations of tar and specimens were taken to be separated. As work for the public transit Red Line is extended, museum researchers know that more tar pits will be uncovered, for example near the intersection of Wilshire and Curson.[5]

La Brea animals and plants

Active excavation site at La Brea Tar Pits, 2008

Among the prehistoric species associated with the La Brea Tar Pits are mammoths, dire wolves, short-faced bears, ground sloths, and the state fossil of California, the saber-toothed cat, Smilodon californicus. Only one human has ever been found, a partial skeleton of a woman, dated at approximately 9,000 BP (Enchanged Learning: La Brea). Much of the early work in identifying species was performed in the early 20th century by John C. Merriam of the University of California.

The park is known for producing myriad mammal fossils dating from the last ice age. While mammal fossils occupy significant interest, other fossils, including fossilized insects and plants, and even pollen grains, are also valued. These fossils help define a picture of what is thought to be a cooler, moister climate present in the Los Angeles basin during the glacial age. Among these fossils are microfossils. Microfossils are retrieved from a matrix of asphalt and sandy clay by washing with a solvent to remove the petroleum, then picking through the remains under a high-powered lens.

Tar pits around the world are unusual in accumulating more predators than prey. The reason for this is unknown, but one theory is that a large prey animal (say, a mastodon) would die or become stuck in a tar pit, attracting predators across long distances. This predator trap would catch predators along with their prey. Another theory is that dire wolves and their prey may have been trapped during a hunt. Since modern wolves hunt in packs, each prey animal could take several wolves with it.

Mammals

Sculpture of saber-tooth cats at La Brea Tar Pits, 1956

Below is a partial list of extinct and extant animals with their scientific names included on the right side. This is a selection from the complete catalogue. The dagger symbol "†" indicates an extinct species.

Herbivores

Carnivores

Omnivores

Birds

A partial list of extinct and extant birds found as fossils at La Brea.

Reptiles, amphibians, and fish

Arthropods

Plants

Further information

Brea is Spanish for "tar," making "The La Brea Tar Pits" a redundant expression meaning "The The Tar Tar Pits" (an example of pleonasm). The "tar" pits were used as a source of asphalt (for use as low-grade fuel and for waterproofing and insulation) by early settlers of the Los Angeles area. They mistook the bones in the pits for the remains of pronghorn antelope or cattle that had become mired.

Rancho La Brea is the most famous, but there are two other asphalt pits with fossils in southern California: in Carpinteria, Santa Barbara County and McKittrick, in Kern County. There are other fossil-bearing asphalt deposits in Texas, Peru, Trinidad, Iran, Russia, and Poland.

For other rich deposits, fossilized where they occurred, see Lagerstätten.

La Brea in popular culture

  • In the 1997 disaster film Volcano, a volcano grows out of the largest pool of tar (after the mammoth in the diorama sinks into it), spewing a river of hot lava down Wilshire Boulevard.
  • The pits were also featured in the final scene of the movie Miracle Mile, as well as several other movies representative of Los Angeles.
  • In Steven Spielberg's 1979 film 1941, Captain Wild Bill Kelso, played by John Belushi, shoots down a plane that he mistook for a Japanese plane into the La Brea Tar Pits.
  • In Last Action Hero, the character "Jack Slater" (Arnold Schwarzenegger) falls into the tar pits but quickly swims out and easily wipes himself clean, which the film's protagonist points out as an action-film cliché. An incorrect dinosaur model is shown in the pit, as a mocking reference to the same year's Jurassic Park.
  • The tar pits are also featured in a key scene in "Alan Smithee's" Burn Hollywood Burn.
  • The episode "That's Lobstertainment!" of Futurama depicts an animated version of the tar pits. Fry notices a caveman skeleton with club and wearing an animal skin, causing him to exclaim, "I don't believe it, Sylvester Stallone!"
  • In The Two Jakes a scene takes place at the La Brea Tar Pits.
  • Hidden underneath the museum at the La Brea Tar Pits is the secret base of the heroes of Brian K. Vaughan's comic book Runaways.
  • In My Girl 2, a scene occurs in which Nick pretends to throw Vada's very special ring into the tar pits.
  • In The Simpsons episode "Bart Gets an Elephant", they visit a tar pit attraction modeled on the La Brea Tar Pits.
  • In the novel Mammoth by John Varley, a large part of the plot occurs in and around La Brea in the past and present.
  • In the novel City Of Bones by Michael Connelly The tar pits are mentioned in connection with Los Angeles oldest known murder victim who was murdered 9000 years ago.
  • In the 1948 Warner Brothers cartoon "My Bunny Lies Over the Sea," Bugs Bunny is tunneling to Los Angeles intending to visit the La Brea Tar Pits and accidentally winds up in Scotland. [2] That sets up this heavily-brogued line by the kilted Scotsman that Bugs meets: "Therrr'es no La Brrrea Tarrr Pits in Scotland!"
  • In an episode of Kong: The Animated Series, Kong and his human friends go to Los Angeles where they fight the series villain Ramone De La Porta in front of the La Brea Tar Pits. The villains use the (non-existent) dinosaur bones in the pits to create monsters which Kong fights.
  • In the ABC sitcom Dinosaurs, which takes place in prehistoric times, there is a reference to the pits in Bob LaBrea, an ancient dinosaur chief, for which the main characters' school, LaBrea High School, is named, despite the fact that no dinosaur bones have been found in the Tar Pits.
  • The Mighty Max series features an episode entitled Tar Wars which is centered around the tar pits.
  • The Flintstones regularly make reference to the La Brea Tar Pits though no dinosaur or hominid bones (beyond those of a woman) have been found.
  • In the 1990 film Bad Influence, a scene occurs in which James Spader's & Christian Clemenson's characters attempt to cover up a murder committed by Rob Lowe's character by placing a deceased woman in the La Brea Tar Pits. Her body is pulled from the pit the following day with emergency rescue personnel hovering over the actual pit.
  • The Aqua Teen Hunger Force episode PDA contains a parody of the La Brea Tar Pits which puts its location as Trenton, New Jersey.
  • The main protagonist of Robert Masello's horror novel, "The Bestiary" works on a dig at the La Brea Tar Pits. Though not integral to the story, the discovery of the 9000-year old fossilized remains of a couple forms one of the subplots of the book.
  • The site is frequently mentioned in the novelty song Pico and Sepulveda.
  • In the 1990s PBS game show Where in the World Is Carmen Sandiego? Top Grunge stole the La Brea Tar Pits.
  • In the Teen novel POSEUR, 2008, Janie and Evan discuss the tar pits, mentioning that, on a field trip when they were younger, they were told by a very strange tour guide that the mammoth in the diorama was alive, just staying very still so that he would not sink deeper into the tar.
  • In Moonlight (TV series), setting LA, Episode 13, Fated to Pretend, Josef mentioned that the only person he had killed that week was in the LA Tar Pits.
  • In the 2007 movie The Hammer, the main character Jerry Ferro (Adam Corolla) goes on a date to the tar pits and Page Museum with Lindsay Pratt, played by Heather Juergensen who actually lives near the park in real life.
  • In the fourth novel of Science Fiction author Philip Jose Farmer's World of Tiers series, the hero, Kickaha is chased past the LA Tar Pits.
  • In the song The Smithsonian Institute Blues (or The Big Dig) on the album Lick My Decals Off, Baby by Captain Beefheart. Line: "The way it's goin' at the La Brea tar pits, you know you just can't lose. The new dinosaurs walkin' in the old one's shoes."
  • The La brea Tar Pit is alive and sitting as Tar Pit in Zoo Tycoon: Dinosaur Digs.
  • Rapper DOOM is quoted as saying "Chucked it in the old tar pit off La Brea" in his song "That's That" from his 2009 album, Born Like This.

See also

References

  1. ^ LA okay. "LA okay: Rancho La Brea". LA okay web site. www.laokay.com/. Retrieved 2009-02-21., from "Historic Adobes of Los Angeles County by John R. Kielbasa ISBN 0-8059-4172-X"
  2. ^ Jia-Rui Chong, Researchers learn why tar pits are bubbly, Los Angeles Times, May 14, 2007.
  3. ^ M. Albano, personal observation
  4. ^ Page Museum. "Page Museum - La Brea Tar Pits". Page Museum web site. The Natural History Museum of Los Angeles County Foundation. Retrieved 2006-12-15.
  5. ^ a b c "Cache Of Ice Age Fossils Found Near Tar Pits". Los Angeles: KCBS. Associated Press. February 18, 2009. Retrieved February 18, 2009.
  6. ^ a b Thomas H. Maugh II (February 18, 2009). "Major cache of fossils unearthed in L.A." Los Angeles Times. Los Angeles. Retrieved February 18, 2009.
  7. ^ "Workers Unearth Mammoth Discovery near La Brea Tar Pits". Los Angeles: KTLA. February 18, 2009. Retrieved February 18, 2009.
  8. ^ "Nearly intact mammoth found at L.A. construction site". USA Today. February 18, 2009. Retrieved February 18, 2009.

External links

Wikimedia Commons has media related to La Brea Tar Pits.

34°03′46″N 118°21′22″W / 34.062828°N 118.355992°W / 34.062828; -118.355992

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