Petrified wood (from the Greek root petro meaning "rock" or "stone") is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree having turned completely into stone by the process of permineralization. All the organic materials have been replaced with minerals (most often a silicate, such as quartz),
while retaining the original structure of the wood. Unlike other types of fossils which are typically impressions or compressions, petrified wood is a three dimensional representation of the original organic material. The petrifaction process occurs underground, when wood becomes buried under sediment and is initially preserved due to a lack of oxygen which inhibits aerobic decomposition.
Mineral-laden water flowing through the sediment deposits minerals in the plant's cells and as the plant's lignin and cellulose decay, a stone mould forms in its place.
Locations
* Argentina - The Petrified Forest National Monument in Chubut Province in the Argentine Patagonia has many trees that measure more than 3 m (10 ft) in diameter and 30 m (100 ft) long.
* Australia - Has deposits of petrified and opalised wood. Chinchilla, Queensland is famous for its 'Chinchilla Red'.
* Belgium - Geosite Goudberg near Hoegaarden.
* Brazil - In the geopark of Paleorrota, there is a vast area with petrified trees.
* Canada - In the badlands of southern Alberta; petrified wood is the provincial stone of Alberta. Axel Heiberg Island in Nunavut has a large petrified forest.
* China - in the Junggar Basin of Xinjiang, northwest China government has issued a crackdown on collecting of this material, but large slabs and even large meeting tables have been made out of this colorful replaced wood.
* Czech Republic, Nová Paka - The most famous locality on Permian-Carboniferous rocks in the Czech Republic.
* Germany - The museum of natural history in Chemnitz has a collection of petrified trees found in the town in 1737.
* Ecuador - Puyango petrified forest. One of the largest collections of petrified woods in the world.
* Egypt petrified forest in Cairo-Suez road, declared a national protectorate by the minstery of environment, also in the area of New Cairo at the Extension of Nasr city,
* Greece - Petrified Forest of Lesvos, at the western tip of the island of Lesbos, is possibly the largest of the petrified forests, covering an area of over 150 km² and declared a National Monument in 1985. Large, upright trunks complete with root systems can be found, as well as trunks up to 22 m in length.
* India- A geological site famous for its petrified woods Thiruvakkarai Village in Chennai, Tamil Nadu.
* Libya - Great Sand Sea - Hundreds of square miles of petrified trunks, branches and other debris mixed with Stone Age artifacts.
* Namibia - Petrified forest of Damaraland
* New Zealand - Curio Bay on the Catlins coast contains many petrified wood examples.
* Ukraine - Petrified araucaria trunks near Druzhkivka.
* United Kingdom - many examples of petrified submerged forests can be found at low tide around the coast of England and Wales.[8]
* United States - Some of the better known petrified wood sites include:
o Petrified Wood Park in Lemmon, South Dakota.
o Ginkgo/Wanapum State Park in Washington State.
o Grotto of the Redemption, a private park in Iowa.
o Petrified Forest National Park in Arizona.
o Petrified Forest (California) in California.
o Mississippi Petrified Forest in Flora, Mississippi.
o Florissant Fossil Beds National Monument near Florissant, Colorado.
o Yellowstone National Park in Wyoming.
o The south unit of Theodore Roosevelt National Park outside Medora, North Dakota.
