Permineralization is a type of fossilization involving deposits of minerals within the cells of organisms. Water rich in dissolved solids seeps into the pores of organic tissue and forms a crystal cast with deposited minerals.
Crystals begin to form in the porous cell walls. This process continues on the inner surface of the walls until the central cavity of the cell, the lumen , is completely filled. The cell walls themselves remain intact surrounding the crystals. Most dinosaur bones are permineralized. Permineralization is the first step in petrification.
In petrification, the cellulose cell walls are completely replaced by minerals. So the petrified wood you may find along Roller Coaster Ridge is an exact duplicate of a tree that lived there 3. Petrified wood can be spectacular to behold, because it generally retains the cellular structure of the original wood. So you can see that same beautiful wood grain, but it has been preserved and rendered as stone. All kinds of minerals can be involved in this transformation, so you can see a dazzling array of colors and textures in a single fossil.
Typically, it is found in deposits of sedimentary or volcanic rock. You can identify the type of wood which was fossilized in the first place. Or you can identify the minerals which have taken over the structure of the wood.
According to the National Park Service, there are nearly a dozen different types of petrified trees in the Petrified Forest in Arizona, and likely still more species of petrified trees located on the site that researchers have not yet identified. The trees found in the park include ginkgoes, tree ferns, and coniferous species. Many of these species are related to modern species of trees, but remember, these are prehistoric specimens. So if you find a piece of petrified ginkgo, it can be identified as an ancestral relative of modern ginkgo, but it will not be exactly the same.
You may also find petrified examples of trees like redwoods which have been around since prehistoric times. Modern trees can be petrified, and someday, rock hunters will probably discover fossilized examples of all the familiar trees we live among. Interestingly enough, scientists have managed to artificially induce the fossilization process in a laboratory using an acid-leaching method.
This process remarkably took only days, but in nature, the fossilization of wood takes millions of years. In short, any type of wood can be petrified. But what you find in nature while rock hunting will be prehistoric. The best way to figure out what type of petrified wood you are looking at is to examine the cell structure. Get help. Password recovery. Geology Page. Home Latest News Video. Debris Flow Dynamics. Sampling Hot Molten Lava. Incredible moment Anak Krakatau erupts, Oct Download Google Earth For Free.
Remote Sensing Downloader. Thunder Egg. Home Geology What is Petrified Wood? Click to Shop our fossils, minerals, educational materials! Subscribe to RSS. Petrified wood is a term used for fossilized wood. Basically, this means that when the tree dies, it is turned to stone due to small amount of mineral deposits filling the cells of the organism. Minerals from ground water, lakes, or oceans seep into the pores of organic tissue and leave deposits, slowly creating crystals within it.
This process continues on the inner surface of the walls until the central cavity of the cell is completely filled. This process is also referred to as petrification. Petrification usually happens underground, as the plant matter dies and is covered by sediment, volcanic ash, etc. If the ground where the trees are buried has lots of water in it the wood is protected from oxygen.
Decomposition required oxygen, so the plant matter does not decompose, allowing petrification to happen. This can happen rather quickly due to the fact that water is already underground. How convenient! It infiltrates the organic matter, and begins the petrification process.
When this occurs in highly wooded area, such as forests, its called……you guessed it, a petrified forest.
0コメント