Petrified wood

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The image shows the center of a polished slice of a petrified tree from the Late Triassic Epoch (approximately 230 million years ago) found in Arizona. The remains of insects can be detected in an enlarged image. Polished slice of petrified wood.jpg
The image shows the center of a polished slice of a petrified tree from the Late Triassic Epoch (approximately 230 million years ago) found in Arizona. The remains of insects can be detected in an enlarged image.
Petrified log in Paleorrota geopark, Brazil Parque paleobotanico de Mata..JPG
Petrified log in Paleorrota geopark, Brazil
Petrified log at the Petrified Forest National Park PetrifiedWood.jpg
Petrified log at the Petrified Forest National Park
Polished petrified wood Petrified Wood Wooster.jpg
Polished petrified wood
The outline of cells visible in a segment of petrified wood Polished petrified wood cells.jpg
The outline of cells visible in a segment of petrified wood
Polished slice of petrified wood Petrified wood closeup 2.jpg
Polished slice of petrified wood
Petrified logs Petrified Forest National Park Wood.jpg
Petrified logs
Petrified Acacia wood Petrified Acacia Wood.JPG
Petrified Acacia wood
Puyango petrified forest Puyango fossil tree 02.JPG
Puyango petrified forest
Petrified log and Welwitschia at Namibia Petrified forest (2014) Petrified tree trunk and Welwitschia (Namibia).jpg
Petrified log and Welwitschia at Namibia Petrified forest (2014)

Petrified wood (from the Latin root petro meaning "rock" or "stone"; literally "wood turned into stone") 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 (mostly a silicate, such as quartz), 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.

Fossil Preserved remains or traces of organisms from a past geological age

A fossil is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood, oil, coal, and DNA remnants. The totality of fossils is known as the fossil record.

Terrestrial plant

A terrestrial plant is a plant that grows on, in, or from land. Other types of plants are aquatic, epiphytic and lithophytic.

Tree Perennial woody plant with elongated trunk

In botany, a tree is a perennial plant with an elongated stem, or trunk, supporting branches and leaves in most species. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. Trees are not a taxonomic group but include a variety of plant species that have independently evolved a woody trunk and branches as a way to tower above other plants to compete for sunlight. Trees tend to be long-lived, some reaching several thousand years old. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees. Trees have been in existence for 370 million years. It is estimated that there are just over 3 trillion mature trees in the world.


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. [1] The process lasts millions of years. [2] A forest where such material has petrified becomes known as a petrified forest.

Petrifaction The process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with mineral

In geology, petrifaction or petrification is the process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with minerals. Petrified wood typifies this process, but all organisms, from bacteria to vertebrates, can become petrified. Petrifaction takes place through a combination of two similar processes: permineralization and replacement. These processes create replicas of the original specimen that are similar down to the microscopic level.

Sediment Particulate solid matter that is deposited on the surface of land

Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension in river water and on reaching the sea bed deposited by sedimentation. If buried, they may eventually become sandstone and siltstone through lithification.

Volcanic ash volcanic material formed during explosive eruptions with the diameter of the grains less than 2 mm

Volcanic ash consists of fragments of pulverized rock, minerals and volcanic glass, created during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer to all explosive eruption products, including particles larger than 2 mm. Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere. The force of the escaping gas shatters the magma and propels it into the atmosphere where it solidifies into fragments of volcanic rock and glass. Ash is also produced when magma comes into contact with water during phreatomagmatic eruptions, causing the water to explosively flash to steam leading to shattering of magma. Once in the air, ash is transported by wind up to thousands of kilometers away.


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 another tint.

Manganese Chemical element with atomic number 25

Manganese is a chemical element with symbol Mn and atomic number 25. It is not found as a free element in nature; it is often found in minerals in combination with iron. Manganese is a transition metal with important industrial alloy uses, particularly in stainless steels.

Iron Chemical element with atomic number 26

Iron is a chemical element with symbol Fe and atomic number 26. It is a metal, that belongs to the first transition series and group 8 of the periodic table. It is by mass the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust.

Copper Chemical element with atomic number 29

Copper is a chemical element with symbol Cu and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement.

Following is a list of contaminating elements and related color hues: [3] [4]

Carbon Chemical element with atomic number 6

Carbon is a chemical element with symbol C and atomic number 6. It is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Three isotopes occur naturally, 12C and 13C being stable, while 14C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity.

Chromium Chemical element with atomic number 24

Chromium is a chemical element with symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard and brittle transition metal. Chromium is also the main additive in stainless steel, to which it adds anti-corrosive properties. Chromium is also highly valued as a metal that is able to be highly polished while resisting tarnishing. Polished chromium reflects almost 70% of the visible spectrum, with almost 90% of infrared light being reflected. The name of the element is derived from the Greek word χρῶμα, chrōma, meaning color, because many chromium compounds are intensely colored.

Cobalt Chemical element with atomic number 27

Cobalt is a chemical element with symbol Co and atomic number 27. Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.

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 (anaerobic environment), 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 red and green hues that can be seen in rarer specimens.


Areas with a large number of petrified trees include:

See also

Related Research Articles

Petrified Forest National Park national park of the United States

Petrified Forest National Park is an American national park in Navajo and Apache counties in northeastern Arizona. Named for its large deposits of petrified wood, the fee area of the park covers about 230 square miles, encompassing semi-desert shrub steppe as well as highly eroded and colorful badlands. The park's headquarters is about 26 miles (42 km) east of Holbrook along Interstate 40 (I-40), which parallels the BNSF Railway's Southern Transcon, the Puerco River, and historic U.S. Route 66, all crossing the park roughly east–west. The site, the northern part of which extends into the Painted Desert, was declared a national monument in 1906 and a national park in 1962. The park received 644,922 recreational visitors in 2018. Typical visitor activities include sightseeing, photography, hiking, and backpacking.

<i>Araucarioxylon arizonicum</i> species of plant

Araucarioxylon arizonicum is an extinct species of conifer that is the state fossil of Arizona. The species is known from massive tree trunks that weather out of the Chinle Formation in desert badlands of northern Arizona and adjacent New Mexico and Chemnitz petrified forest in Chemnitz, Germany, most notably in the 378.51 square kilometres Petrified Forest National Park. There, these trunks are locally so abundant that they have been used as building materials.

Ginkgo Petrified Forest State Park

Ginkgo Petrified Forest State Park/Wanapum Recreational Area is a geologic preserve and public recreation area covering 7,124-acre (2,883 ha) on the western shoreline of the Columbia River's Wanapum Reservoir at Vantage, Washington. Petrified wood was discovered in the region in the early 1930s, which led to creation of the state park as a national historic preserve. Over 50 species are found petrified at the site, including ginkgo, sweetgum, redwood, Douglas fir, walnut, spruce, elm, maple, horse chestnut, cottonwood, magnolia, madrone, sassafras, yew, and witch hazel.

Fossil wood wood that is preserved in the fossil record

Fossil wood is wood that is preserved in the fossil record. Over time the wood will usually be the part of a plant that is best preserved. Fossil wood may or may not be petrified. The study of fossil wood is sometimes called palaeoxylology, with a "palaeoxylologist" somebody who studies fossil wood.

Petrified forest of Lesbos

The petrified forest of Lesbos is a petrified forest on Lesbos in Greece.

Gallatin Range mountain range

The Gallatin Range is a mountain range of the Rocky Mountains, located in the U.S. states of Montana and Wyoming. It includes more than 10 mountains over 10,000 feet (3,000 m). The highest peak in the range is Electric Peak at 10,969 feet (3,343 m).

National Fossil Wood Park, Tiruvakkarai

The National Fossil Wood Park, Tiruvakkarai is a notified National Geo-heritage Monument located in the Villupuram District in the Indian state of Tamil Nadu and is maintained by the Geological Survey of India. The park was established in 1940 and is located 1 km east of Thiruvakkarai village on the road between Tindivanam and Pondicherry.

<i>Psaronius</i> genus of plants (fossil)

Psaronius was a Marattialean tree fern which grew to 10m in height, and is associated with leaves of the organ genus Pecopteris and other extinct tree ferns. Originally, Psaronius was a name for the petrified stems, but today the genus is used for the entire tree fern. Psaronius tree fern fossils are found from the Carboniferous through the Permian.

Specimen Ridge mountain in United States of America

Specimen Ridge, el. 8,379 feet (2,554 m) is an approximately 8.5-mile (13.7 km) ridge along the south rim of the Lamar Valley in Yellowstone National Park. The ridge separates the Lamar Valley from Mirror Plateau. The ridge is oriented northwest to southeast from the Tower Junction area to Amethyst Mountain. The ridge is known for its abundance of amethyst, opal and petrified wood. It was referred to as Specimen Mountain by local miners and was probably named by prospectors well before 1870. The south side of the ridge is traversed by the 18.8-mile (30.3 km) Specimen Ridge Trail between Tower Junction and Soda Butte Creek. The trail passes through the Petrified Forest and over the summit of Amethyst Mountain el. 9,614 feet (2,930 m).

Escalante Petrified Forest State Park

Escalante Petrified Forest State Park is a state park of Utah, USA, located a half-mile (0.8 km) north of the town of Escalante. A visitor center was built in 1991, and features displays of plant and marine fossils, petrified wood and fossilized dinosaur bones over 150 million years old. The Petrified Forest Trail is a one-mile (1.6 km) loop, winding up the side of a mesa to the top where most of the fossil wood occurs. Logs two feet or more in diameter are seen at several places along the trail where it is eroding from the conglomerate capping the mesa. This conglomerate lies near the top of the Brushy Basin Member of the Morrison Formation. The wood is multicolored and was prized by hobbyists before the Park was established. The logs are believed to be of conifers that were transported by a river before being buried and later fossilized as agate. A 50 foot (15m) log is displayed near the trail head and is one of the most complete fossil logs known from the Morrison Formation.

Chemnitz petrified forest

The Chemnitz petrified forest is a petrified forest in Chemnitz, Germany.

<i>Tietea singularis</i> species of plant

Tietea singularis was a Marattialean tree fern from the Late Carboniferous to Permian which grew up to 12 metres (39 ft) in height. It is estimated to represent close to 90% of some fossil assemblages in Brazil.

Petrified forest, Khorixas

The Petrified forest, located 42 kilometres (26 mi) west of the Namibian town of Khorixas, on the C39 road, is a deposit of large tree trunks that have "turned to stone" through a process of diagenesis. There are at least two large tree trunks, each 45 metres (148 ft) long, exposed to view. Several hundred others are located in the vicinity.

Bosques Petrificados de Jaramillo National Park national park in Argentina

The Jaramillo Petrified Forest National Park is a protected area of petrified forest located in the Deseado Department, in the northeast of Santa Cruz Province, Argentina. Formerly part of the site was a natural monument, established in 1954 and known as the Petrified Forest Natural Monument, covering about 13,700 hectares. This area has remnants of a forest preserved in stone, that had been growing on the site before the upthrust of the Andes some 150 million years ago. In December 2012, further land was added and the protected area was reclassified as a national park with a total area of 78,543 hectares.

Puyango Petrified Forest

Puyango Petrified Forest is a fossil deposit of petrified wood located in the middle basin of the Puyango River, between the Ecuadorian provinces of El Oro and Loja. The area covers 2,658 hectares and its sediments are divided into four geological formations, dating from the late Cretaceous period. These deposits are rich in both fossilized trunks and leaves - which belonged to the typical Mesozoic flora - as well as fossils of invertebrates such as bivalves, ammonites, echinoderms, among others.

Akal Wood Fossil Park

Akal Wood Fossil Park is a National Geological Monument of India located in Jaisalmer district, Rajasthan.


Arthropitys is an extinct genus of calamitacean equisetale. The petrified fossils of Arthrophitys bistriata, the type species, can be found at Chemnitz petrified forest, Chemnitz, Germany.

Goderdzi Petrified Forest Natural Monument

The Goderdzi Petrified Forest Natural Monument is a natural monument in Georgia.


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