Petrified wood

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"Petrified forest" redirects here. For the 1936 film, see The Petrified Forest.
The image shows the center of a polished slice of a petrified tree from the late Triassic period (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
Petrified log at the Petrified Forest National Park
Polished petrified wood
Polished slice of petrified wood
Petrified logs
The outline of cells visible in a segment of petrified wood
Petrified stump exposed at low tide on Ynyslas beach, Wales
Petrified Acacia wood
Puyango petrified forest

Petrified wood (from the Greek 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. 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; as the plant's lignin and cellulose decay, a stone mould forms in its place. The organic matter needs to become petrified before it decomposes completely.[1] A forest where such material has petrified becomes known as a petrified forest.

Elements[edit]

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:

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Petrified wood is a fossil in which the organic remains have been replaced by minerals in the slow process of being replaced with stone.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 flowing through the tissues, replacing the organic plant structure with inorganic stone. The end result is petrified wood, a plant, with its original basic structure in place, replaced by stone. This process could occur in less than one thousand years.[citation needed] Exotic minerals allow the rare red and green hues that can be seen in more rare specimens.

Locations[edit]

Areas with a large number of petrified trees include:

Artificial petrified wood[edit]

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.[11][12]

See also[edit]

References[edit]

External links[edit]