Los Angeles is for Hikers
Get out and explore any of the 82 great hiking trails located right here in L.A. This guide book features short and long day hikes while keeping you close to home. Shop here.
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Support Today's Scientists, Inspire Tomorrow's Scientists
When you give to the Museum, you support our scientists' research on the planet's biodiversity. You are also creating tomorrow's scientists. Our teacher resources make each field trip a learning experience, our education outreach brings the science of discovery to schools all over L.A. Learn more >
Rancho La Brea Geology
Why does asphalt seep to the surface in the middle of Los Angeles? Click here to learn about the geology of the area.
A T. rex in Three Dimensions
Do you want to be a junior paleontologist? Experience the thrill of putting a T. rex back together in the Discovery Center. It's like a puzzle, but in 3-D! Learn more >
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Red Rock Canyon Gomphothere Preparation
Fossil preparation or cleaning is carried out at the Museum's Vertebrate Paleontology Lab. The Gomphothere (extinct shovel tusk elephant) tusk featured on this page was collected on our Fall 2006 family field trip (September 29 - October 1, 2006) and was found by Howard Lichtman. The tusk is approxiamately 9.5 - 10 million years old. Vertebrate fossils are often delicate and can not be easily removed in the field. Paleontologists use jackets to protect the fossil, both from the ride back to the Museum and from environmental conditions that might damage it. Jacketing a fossil means wrapping it like you would wrap a broken bone. The jacket itself is composed of strips of strong material, usually burlap, and plaster that is mixed on site. Excess rock is included in the jacket to help protect it. Once a fossil has been removed from a site, it is taken to the preparation lab where the meticulous work of preparation is carried out. The process of fossil preparation is a long and tedious one. Using tools like brushes, dental instruments, and air scribes fossil preparators and volunteers remove any surrounding sediment from the fossil surface. Air scribes are basically tiny jackhammers with a rotating tip to break up rock, and a steady stream of air to blow away debris. As the preparator works the fossil is slowly exposed for the first time in thousands, millions, even hundreds of millions of years. During this process the fossil bone may crack or break. Broken pieces are secured with strong adhesives and unstable areas strengthened with consolidants. Once prepared the fossil is ready to be included in the Museum's collections for study by other paleontologist or display.
October 4, 2006
Howell Thomas, Senior Paleontological Preparator (right), and volunteer Donna Dameron (left), slowly remove rock (matrix) surrounding the Gomphothere tusk using air scribes in the Museum's Vertebrate Paleontology Preparation Lab. Air scribes are being used on this project because the surrounding rock is a hard coarse sandstone and this is the most effective way to remove the rock without damaging the fossil tusk.
October 4, 2006
Portion of the tusk slowly being revealed from the surrounding rock. The tusk is the brown object in the photo. Note how coarse the surrounding rock is.
October 4, 2006
Donna uses an air scribe to slowly remove the surrounding rock. Exposed portion of the tusk is to the left.
October 4, 2006
Howell works carefully to remove the surrounding rock from around the tusk with an air scribe. There is a plane of resistance along the surface of the fossil tusk, so rock flakes away just before the air scribe tip touches the surface. A light touch is necessary for this kind of work so no damage is done to the fossil.
October 4, 2006
Overhead view of Howell and Donna starting to uncover more of the tusk. Eventually most of the sandstone surrounding the tusk in the jacket will be removed.
October 11, 2006
After six days of work the tusk is fully exposed and most of the excess rock removed. Over 3 feet long, the tusk is nearly complete with only the tip missing (not preserved). The tip of the tusk would have been to the left in the photo.
