Petrified wood is the name given to a special type of fossilized remains of
terrestrial vegetation. It is the result of a tree or tree-like plants having
completely transitioned to stone by the process of permineralization. All the
organic materials have been replaced with minerals, while retaining the
original structure of the stem tissue. 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 or volcanic ash
and is initially preserved due to a lack of oxygen which inhibits aerobic
decomposition. Mineral-laden water flowing through the covering material
deposits minerals in the plant's cells; as the plant's lignin and cellulose
decay, a stone mold forms in its place. The organic matter needs to become
petrified before it decomposes completely. A forest where such material
has petrified becomes known as a petrified forest.
Elements Elements such as manganese, iron, and
copper in the water/mud during the petrification process give petrified
wood a variety of color ranges. Pure quartz crystals are colorless, but when
contaminants are added to the process the crystals take on a yellow, red, or
other tint. Following is a list of contaminating
elements and related color hues: carbon – black
cobalt – green/blue chromium – green/blue
copper – green/blue iron oxides – red, brown, and yellow
manganese – pink/orange manganese oxides – blackish/yellow
Petrified wood can preserve the original structure of the stem in all its detail,
down to the microscopic level. Structures such as tree rings and the
various tissues are often observed features.
Petrified wood is a fossil in which the organic remains have been replaced by
minerals in the slow process of being replaced with stone. This petrification
process generally results in a quartz chalcedony mineralization. Special rare
conditions must be met in order for the fallen stem to be transformed into
fossil wood or petrified wood. In general, the fallen plants get buried in
an environment free of oxygen, which preserves the original plant structure
and general appearance. The other conditions include a regular access to
mineral rich water in contact with the tissues, replacing the organic plant
structure with inorganic minerals. The end result is petrified wood, a plant,
with its original basic structure in place, replaced by stone. Exotic
minerals allow the rare red and green hues that can be seen in more rare
specimens. Locations
Areas with a large number of petrified trees include:
Argentina – the Petrified Forest National Monument in Santa Cruz Province
in the Argentine Patagonia has many trees that measure more than 3 m in
diameter and 30 m 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. Petrified forests of
dicksoniaceae and arthropitys can also be found in the states of São Paulo and
Tocantins. 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. In and around the
North Saskatchewan river, around the Edmonton area.
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 the colorful petrified 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, from the in situ
Chemnitz Petrified Forest, found in the town since 1737.
Ecuador – Puyango petrified forest. One of the largest collections of petrified
wood 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, El Qattamiyya, near El
Maadi district, and Al Farafra oasis. France – petrified forest in the village
of Champclauson 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 known for its
petrified wood Thiruvakkarai Village in Chennai, Tamil Nadu. The site is
protected by the Geological Survey of India. Petrified wood covers a large
area in this site. Petrified Wood has also been discovered in Dholavira in
Kutch, Gujarat, dating back to 187-176 million years.
Indonesia – petrified wood covers several area in Banten and also in some
part of Mount Halimun Salak National Park.
Israel – several examples of petrified wood occur in the HaMakhtesh HaGadol in
the Negev desert. 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. Fossil Forest, Takapuna, Auckland, New
Zealand Saudi Arabia – petrified forest north of
Riyadh Thailand – Bantak Petrified Forest Park
in Ban Tak District 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.Fossil Grove, Glasgow, Scotland
Fossil Forest, Dorset, England United States – petrified wood sites
include: Petrified Wood Park in Lemmon, South
Dakota Ginkgo/Wanapum State Park in Washington
State Petrified Forest National Park in
Arizona Petrified Forest in California
Mississippi Petrified Forest in Flora, Mississippi
Florissant Fossil Beds National Monument near Florissant, Colorado
Yellowstone Petrified Forest and Gallatin Petrified Forest, Yellowstone
National Park, Wyoming The south unit of Theodore Roosevelt
National Park outside Medora, North Dakota
Gilboa Fossil Forest, New York Escalante Petrified Forest State Park in
Utah Agate Desert in the Upper Rogue River
Valley near Medford, Oregon Artificial petrified wood
Artificial petrified wood has been produced in a Washington laboratory. In
the process, small cubes of pine are soaked in an acid bath for two days,
then in a silica solution for another two. The product is then cooked at 1400
°C in an argon atmosphere for two hours. The result was silicon carbide ceramic
which preserved the intricate cell structure of the wood.
See also Amethyst Mountain
Araucarioxylon arizonicum Fossil wood
Petrified forest of Lesbos Petrified palmwood
Submerged forest Wood Opal
References External links
The Petrified forest of Lesvos - Protected Natural Monument
The Town Museum of Nová Paka The Mississippi Petrified Forest