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.
