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Still Shrouded in Mystery

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Still Shrouded in Mystery A8 Saturday, November 1, 2014 Imperial Valley Press Land of Extremes QUESTIONS? Contact Local Content Editor Richard Montenegro Brown at [email protected] or 760-337-3453. EDITOR’S NOTE A series of stories on the history of man in our desert and the e orts of the Imperial Valley Desert museum to tell that story will run through October, replacing the Teen page until a new crop of interns return in the fall connected to the IVHigh journalism program. ANCIENT EARTHEN ART Desert geoglyphs’ still shrouded in mystery LEFT: The Blythe Giants are some of the largest humanoid fi g- ures in the US. ABOVE: Geoglyph in the Yuha Desert, with Meg Casey. PHOTOS COURTESY OF IMPERIAL VALLEY DESERT MUSEUM The largest concentration of local geo- glyphs are in a 165-mile band along the Colorado River between Needles and Yuma — not surprising since the Colo- rado River has been the area’s most reli- able source of water for centuries. Their meanings are still shrouded in mystery. BY NEAL V. HITCH This has been done by Special to this Newspaper/Imperial Valley hand, with a stone, or with here are some mysteries that, once dis- a rake or hoe to clear away covered, never let you go. In 1976, Har- stones. Smaller figures are often tamped down into the ry Casey of Brawley began to explore a earth by foot. Tdesert mystery that fascinates him to this day. Dating While taking an archaeolo- Geoglyphs: Ancient While dating these desert gy class with Jay von Werlhof marvels is still an uncertain at IVC, Casey, an avid flier earthen art? science, desert varnish may since high school, enlisted his hold the key. There are hundreds of geo- 1946 Piper J-3 “Cub” plane Geology professor Ron glyphs throughout the deserts for archaeological aerial re- Dorn, with Arizona State Uni- of the extreme southwestern connaissance. versity, has been working with United States, but they re- The project began with a 35 desert varnish for years and main a relatively unknown mm camera and a plane with used it to date many of our phenomenon. Jay von Werlhof and Harry Casey fl y over geoglyphs, July a hole cut in the floor of the local geoglyphs. The largest concentrations 1982. PHOTO COURTESY OF IMPERIAL VALLEY DESERT MUSEUM pilot’s cabin. Desert varnish is not a of geoglyphs (also called in- Casey figured he could fly part of the rock itself, but Their meanings are still es many geoglyphs in highly taglios, or earthen art) are and shoot film at the same paper-thin layers of clay min- shrouded in mystery. trafficked areas and is charged found in western Australia, time. It became an amazing erals blown onto rocks over Ethnographies suggest that with their preservation. northern Chile, southern Peru legacy and a lifelong love. thousands of years. geoglyphs represent creation A few of the best examples, (the famous Nazca Lines) and Harry and his wife, Marga- Minute amounts of organic stories, records of important like the Blythe Giants, are the extreme southwestern ret, (they met during a field matter are trapped in the rock events, mythological events, easily accessible and include United States and adjacent class to the fish traps) have by the varnish, and carbon-14 constellations or astronomical BLM interpretive signs. Mexico. spent the last 38 years travel- dating can be done using Ac- phenomenon (like marking Casey hopes that education The images are best seen ing the Colorado and Mohave celerator Mass Spectrometry the sunrise for solstices). and renewed interest in the from the air and can range deserts exploring earthen (AMS C14) dating. Some geoglyphs are near or geoglyphs will provide further art known as geoglyphs. The from only a few feet to hun- surrounded by dance circles, long-term preservation. Caseys have flown almost dreds of feet in length. suggesting ceremonial or reli- 800 hours, documenting geo- Ancient geoglyphs are near- The geoglyphs of the gious connections. Insuring legacies glyphs across the southwest- ly all found along terraces Colorado Desert The oldest local geoglyph ern United States, Mexico or cliff edges near a reliable Professor Dorn’s AMS C14 Thousands of Casey’s pho- and South America, trying to source of water, like the Colo- The largest concentration of dating study recorded is the tographs — both digital and learn the stories behind their rado and Gila rivers. local geoglyphs are in a 165- “Schneider” geoglyph in the 35 mm — and research notes creation. They are made by removing mile band along the Colorado Yuha Desert (roughly 2,794 are now being preserved in Photographing geoglyphs desert pavement, leaving the River between Needles and BCE), while the youngest (at the Imperial Valley Desert year after year, Casey has creat- lighter under soil as a visible Yuma — not surprising since roughly 840 BCE) is the Win- Museum’s archives as the ed an unparalleled record image. the Colorado River has been terhaven “Trail Guardian.” most recent addition to our of the physical the area’s most reliable source Often geoglyphs can be given collections. changes of the of water for centuries. an estimated date based on Casey’s hope, and the hope geoglyphs in their subject matter. of the museum, is that when the South- For example, hors- fully processed, this collection ern Califor- es were extinct in will provide serious research- nia deserts America until rein- ers with a unique opportunity over the last 38 troduced by the Span- to study the geoglyphs of the years. ish in the 1500s. Colorado and Mohave deserts. This would make the The long-term goal of the “Horse Geoglyph” near Pilot museum is also to curate an Knob one of the youngest lo- exhibit of Casey’s photographs cal geoglyphs, although AMS so that a new generation can C14 dating has not yet been be introduced to the mysteries done on the site. of the geoglyphs. Because they are on the Neal V. Hitch is director of ground, it is often difficult to Casey’s 1946 Piper J-3 “Cub” PHOTO plane COURTESY was a OF crucial IMPERIAL member VALLEY the Imperial Valley Desert see geoglyphs. The BLM fenc- Museum. of the photography team. DESERT MUSEUM.
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