WHAT IS PETRIFIED WOOD ?...

The Word, to petrify, literally means, "turns to stone"Petrified Wood, then, is wood that has turned to stone. The English word is similar to the Greek (piedra) and Latin (pietra) words for stone.Petrified wood is a fossil of a woody plant preserved by permineralization through time by chemical and physical processes. In some cases, fossilized wood is readily identifiable. Generally, the species can be determined by examining thin slices of the fossil under a microscope. The microscopic structure of the fossilized wood is then compared to the cellular structure of living species.

 

 

HOW DOES PETRIFIED WOOD FORM ?...

The process of petrification is not completely understood because researchers have not been able to duplicate the process in the laboratory, where it can be observed and measured. But, certain conditions that must have existed for petrification to accure are known. Oxygen, which causes oxidation or rotting of all types of materials, would have to have been kept away from the dead plant material to prevent it from decaying before it was preserved. Most likely, the dead plant material was deprived of oxygen by being buried by sediments settling in water covering the plants. Much of the fossil wood found today is a product of ancient river and flood plain environment.

 

WHAT HAPPEN AFTER RAPID BURIAL?...

The tree reacts to percolating water. Three things may happen. The log may disintegrate and not be fossilized. The log may be reduced by compression to a coal or it may become petrified. If petrification takes place, minerals from percolating water are deposited in fluid-filled openings in the wood. This process is called permineralization and it preserves the tissues of the wood!In some situations minerals may also substitute for the woody tissues of the log. This process is called replacement. Most petrified woods are permineralized.The entire process is not fully understood but is being actively studied.The final condition, necessary for petrification, is time. The mineral replacement process is very slow, probably taking millions of years.

 

WHAT MINERALS ARE IN PETRIFIED WOOD ?...

The mineral content of petrified wood is easily identified using a mass spectrometer or X-ray diffraction technology. Silica, in the form of silicon dioxide (SiO2), commonly known as quartz, is the most common replacement mineral. Often traces of other minerals give petrified wood its unique color and characteristics. Iron oxide will cause reds, browns, yellows and earth tones. Copper and chrome oxide create greens, silicates of aluminium produce whites, and manganese dioxide makes black.

 

at 03/05/2009 by admin credo

« close news detail