![]() Cellulose is composed of long chains of polymerized glucose arranged into microfibrils that reinforce the cell walls in the wood. Almost half of this is cellulose, which gives wood much of its strength. Together, these substances make up 95% of the dry composition of wood. Wood is composed mostly of holocellulose ( cellulose and hemicellulose) and lignin. The lack of oxygen slows decay of the wood, allowing minerals to replace cell walls and to fill void spaces in the wood. Petrified wood forms when woody stems of plants are buried in wet sediments saturated with dissolved minerals. The blue-green stains are from oxidation of the chalcocite to azurite and malachite. The black wood at left shows unusual mineralization with chalcocite and other sulfide minerals. ![]() The brown wood at right shows conventional silica mineralization. Petrified wood from the Shinarump Formation at the Nacimiento Mine, Cuba, New Mexico. A forest where such material has petrified becomes known as a petrified forest. However, petrified wood is most commonly associated with trees that were buried in fine grained sediments of deltas and floodplains or volcanic lahars and ash beds. Silica in the form of opal-A, can encrust and permeate wood relatively quickly in hot spring environments. ![]() Most of the organic matter often decomposes, however some of the lignin may remain. There needs to be a balance between the decay of cellulose and lignin and mineral templating for cellular detail to be preserved with fidelity. During replacement, the plant's cell walls act as a template for mineralization. Mineral-laden water flowing through the sediments may lead to permineralization, which occurs when minerals precipitate out of solution filling the interiors of cells and other empty spaces. ![]() The presence of water reduces the availability of oxygen which inhibits aerobic decomposition by bacteria and fungi. The petrifaction process occurs underground, when wood becomes buried in water or volcanic ash. Unlike other plant fossils, which are typically impressions or compressions, petrified wood is a three-dimensional representation of the original organic material. In some instances, the original structure of the stem tissue may be partially retained. The organic materials making up cell walls have been replicated with minerals (mostly silica in the form of opal, chalcedony, or quartz). Petrifaction is the result of a tree or tree-like plants having been replaced by stone via a mineralization process that often includes permineralization and replacement. Petrified wood, also known as petrified tree (from Ancient Greek πέτρα meaning 'rock' or 'stone' literally 'wood turned into stone'), is the name given to a special type of fossilized wood, the fossilized remains of terrestrial vegetation. Send us feedback about these examples.Petrified log at the Petrified Forest National Park These examples are programmatically compiled from various online sources to illustrate current usage of the word 'petrified.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Patricia Doherty, Travel + Leisure, 9 June 2022 Namibia, South Africa: The contrasting landscapes of Namibia are epic the deep orange sand dunes that climb 1,000 feet (about the height of the Empire State Building) in height, petrified forests that rise from the middle of the desert and a coastline that appears like a mirage. Peter Debruge, Variety, 12 June 2022 For cooler weather and fascinating places to explore, Teide National Park's volcanic landscape, petrified lava, and panoramic views are the perfect escape from the beach. Casey Mcquiston, Bon Appétit, 22 June 2022 Blaze stands petrified around the corner as the violent scene escalates, involuntarily sharing in the trauma of this brutal, fatal assault. 2022 In the gift shop your brother chases you around a rack of oven mitts with a petrified alligator head until your table is called. 2023 Kamoya Kimeu, the son of a goat herder whose preternatural gift for spotting and identifying petrified tibias, skull fragments and other ancient human remains among the arid, rocky badlands of East Africa won him acclaim as the world’s greatest fossil hunter, died on July 20 in Nairobi, Kenya. Hanya Yanagihara, New York Times, 21 Mar. 2023 Then there were my parents’ collections of books and Japanese and German prints, American quilts and vintage fabrics, petrified stones and hunks of coral. 2021 Kenan's character is petrified that his wife (Brunson) will experience a terrible accident which will force him to give up his dreams to nurse her. Recent Examples on the Web Taken together, these films constitute a loose trilogy, making a virtue of the star’s weathering-and, by now, practically petrified-screen image, while riffing on the very legacy of that image.
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