petrifikaation

Petrification, sometimes rendered as petrifikasjon in some languages, is the natural process by which organic material is preserved as stone through mineralization. In geology and paleontology, petrification refers to the conversion of formerly living tissue into rock by the infiltration and replacement of organic material with minerals carried by water, most commonly silica (as quartz) or calcium carbonate. The result is a fossil that retains fine cellular structure and morphology of the original specimen.

The principal mechanisms are permineralization, whereby mineral-rich fluids fill pore spaces and cavities without destroying the original framework; and replacement, where original tissue completely dissolves and is replaced molecule by molecule with mineral material. Recrystallization can modify mineralogy after initial formation. The minerals often preserve delicate textures, enabling study of ancient organisms and environments.

Petrification requires rapid burial to protect remains from decay, and groundwater rich in dissolved minerals. It typically occurs in sedimentary settings such as river and floodplain deposits, volcanic ash beds, or areas with long hydrothermal activity. Time scales span millions of years. A well-known example is petrified wood, and the Petrified Forest is a notable locality.

Petrification is one form of fossilization; other processes include carbonization, molds and casts, and preservation in amber. In culture, petrification is also used metaphorically to describe something that seems to be turned to stone, often in myths and folklore.