PETRIFIED WOOD

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Petrified Wood was formed 225 million years ago during the Triassic period and

is four times as hard as granite and very colorful due to the effect of impurities such as iron, manganese, copper, and lithium present in the wood during fossilizing process. The Petrified Forest is a spectacular region of fossil logs in the Painted Desert east of Holbrook and south of interstate 40 in Arizona. This area was once part of a large forest that extended from Texas to Utah.

The trees belong to three species of conifers of the family Araucariaceae. In fact, the famiuly is still around today, with the modern representitive being strangley named "Money Puzzle" tree, beacause it is extremly prickly. The most common of all the fossil trees in th Petrified Forest is Araucarioxylon arizonicum. Some opf the l;ogs although now broken intto segments, represent substantial trees which were over fifty meters when they were alive. The conifers excisted at the same time as the dinosaurs (the fossils are also found in the Petrified Forest).

The conifers lived in a region which had a moist and probably warm climate.Washed from up-land areas where they grew, the logs accumulated on the delta flats where they were burned by sands and layers of volcanic ash derived from valcanoes futher to the west. The volcanic ash was the source of the silica which helped to pre-mineralize the logs after trhey were cvered in sediment. The preservation process began during occasional flooding

when some of the trees were buried by a great depth of water and sediment quickly enough to prevent aerobic decay. Over a long period, water contaning dissolved minerals seeped into the wood and replaced the organic cells with stone. Much later, the whole area was uplifted and eroded to give the landscape seen today. These specimens are from private property near, Winslow, Arizona.

 

 

Found on private property near Holbrook, Arizona.

DIMENSIONS: 5 1/4" by 2 3/4" by 4"

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$25.00 (Order #PW01)