Petrified Wood By: Jen Osburn & Hannah Pugh
Some Questions to Answer… • What is petrified wood? • How is it formed? • Why are there multiple colors? • Where can this wood be found? • What has petrified wood been used for? • What are some interesting properties of petrified wood? • Are there any interesting stories associated with it?
What is Petrified Wood? • A fossil in which all of the • organic components • of wood have been replaced • by minerals • The original structure of the • wood is normally preserved • Sometimes the individual • structure of cells can be • distinguished • Tree rings can be observed on many pieces • At the microscopic level, many tissues of the wood • can be identified
The Petrification Process STEP 1: Wood gets buried in sediment. This usually occurs due to volcanic eruptions, mudslides, or other natural disasters.
STEP 2: Water rich in minerals flows through the sediment. STEP 3: The minerals replace the wood’s cells and organic materials with stone over the course of many years.
What is Involved? • Preservation of the “wood” can be attributed to a lack of oxygen. • Most of the minerals involved in the process are silicates. • The structure of the cells of the wood can be preserved so well by that the features can be observed in detail at a microscopic level. • The minerals take the place of the wood’s lignin and cellulose as they decay.
Colors Different elements in the minerals yield different colors in the new fossilized wood. Carbon: Black Cobalt: Green/Blue Chromium: Green/Blue Copper: Green/Blue Iron Oxides: Red, Brown, Yellow Manganese: Pink/Orange Manganese Oxides: Black
Locations The world is constantly changing, most of the land mass at one time was covered in tropical forests, so petrified wood can be found almost anywhere.
The Best Locations… • Argentina • Canadian Badlands • Czech Republic • Greece • Libya • USA • Australia • India
What Can It Be Used For? Paper weight anyone?
Interesting Properties • On the Mohs Hardness Scale, petrified wood is rated with a 7, the same as quartz. • Petrified wood is the state gem of Washington. • Petrified wood generally makes a better pet rock than regular rocks. • Petrified wood is the official state fossil of Arizona. • Petrified wood can weigh thousands of pounds.
Folklore • Many myths and fairy tales have some mention of the petrification process. • The story of Medusa • Basilisks • Children’s games • Various fairy tales
Can It Be Made in a Lab? A lab in the state of Washington has successfully created artificial petrified wood.
References • http://en.wikipedia.org/wiki/Petrified_wood • http://www.scienceviews.com/parks/treestostone.html • http://www.desertusa.com/mag00/jan/papr/rock.html • http://en.wikipedia.org/wiki/Petrifaction