Desert Messenger

January 16, 2013

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Page 26 • • • • • • • www.DesertMessenger.com BUYING Old Costume Jewelry Old Fountain Pens Silver & Gold Coins Sterling Silverware Gold Filled Jewelry Old Watches Gold & Silver Jewelry Any Condition • Gold Nuggets • Dental Gold Hi Ally Swap Meet ~ Front Row Main St., Quartzsite Hand-blown Glass Vases STICKER SALE 20% OFF reg. price! Quiet Times 90 E. Main St., Quartzsite 928-927-8081 Geology of trees The fine art of petrification By Jenn Jedidiah Free Looking out across the desert, with its stately saguaros but few trees, it is difficult to imagine a landscape here covered with dense forest. But in reality, around 250 million years ago, this area of the desert southwest was a full of trees- mostly conifers and palm trees. The environment was similar to a modern tropical environment, and it was because of that tropical, forested environment that Arizona has its state fossil. Petrified wood was designated the state fossil of Arizona in 1988 and we are fortunate to have one of the largest and most colorful concentrations of it in the entire world. Yes, petrified wood is a fossil. It is wood that has been changed to stone through processes known as permineralization and replacement. Two specific conditions must exist in order for After a week like yours, you need a church like ours! Evangelist DAVID WOODS During Annual Camp Meeting Sunday, January 20th at 6pm Love Offering EVERYONE IS WELCOME! 665 W. Tyson, Quartzsite, Arizona • 928-927-5808 January 16, 2013 ADVENTURES WITH ROCKS a fallen tree to turn into petrified wood. First, the fallen tree or limb must get buried in an environment devoid of oxygen, like mud or heavy sediments. In an anaerobic environment, the organic matter will not decompose. The second condition is that there must be mineral-rich water flowing through the sediments and the wood. Permineralization occurs as minerals flow into the original tissues of the wood and replace the organic matter molecule by molecule. Empty spaces in cells are filled with crystals. The original shape and structure of the wood is retained, though all organic matter has been replaced by minerals. This process can take anywhere from hundreds to thousands of years. The final composition of petrified wood will depend on what minerals are present when it is forming. Typically it is some form of quartz or chalcedony with various other minerals found in trace amounts. Here in Arizona, a silica solution produces specimens with varieties of quartz such as agate, jasper, and sometimes opal. The colors in petrified wood are the result of the trace minerals in the solution. Copper, cobalt, or chromium produce a green or blue color for example. Iron oxides create reds, browns, and yellows. Manganese produces pink and orange, while blackish/yellow comes from manganese oxides. Black is the result of an abundance of carbon, and white is created by an excess of silica. In many specimens, environmental events and details such as growth rings, bark, even diseased and damaged areas are preserved. For this reason, petrified wood provides much information -HAUL We sell U BOXES to scientists about life on earth during the Jurassic and Triassic periods, about 250 million years ago. For example, in Wolverine Petrified Forest in Utah, geology of the area revealed flooding that caused trees to fall in large quantities when the ground was undercut by rapid erosion. The trees were covered quickly by the flood sediments and eventually petrified. Upon further study, scientists discovered evidence that many of these ancient trees had been attacked by bark beetles. Preserved in the petrified tree trunks were narrow channels and scarred areas similar to the ones caused by modern day bark beetles. Petrified wood is found throughout the world. Here in Arizona, our beloved Petrified Forest National Park is the most well-known location for petrified wood. Referred to as "Rainbow", the famous specimens from this area are clearly some of the most beautiful petrified wood in the world. But petrified wood can be found in many other places in our great state. Rainbow can be found in other public and private lands in eastern Arizona. Here, near Quartzsite, petrified wood can be found along the Colorado River, near Alamo Lake, and near Signal. The Alamo Lake and Signal specimens are petrified palm wood. Petrified palm bog can also be found near Alamo Lake. Palm bog is a rare form of petrified palm, formed from the roots of palm trees growing in marshy areas. For information and maps to the local collecting sites for petrified wood, visit RocksInMyHead. We are open at Space A37 in Rice Ranch, 605-3768754, www.RocksInMyHead.com. We have a beautiful selection of petrified wood, as well as books, maps, tools and supplies for all your rockhounding, prospecting, and lapidary needs. BEST AUTO OPEN Saturdays RV & TRUCK REPAIR S ! ERVICE YOU CAN DEPEND ON 585 N. Central Quartzsite Open Mon-Fri 8-5 Johnny DelPino, Owner 928-927-8787

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