Petrified Wood Formation
Name: Lucas H.
Date: January 22, 2004
How is petrified wood formed?
A tree or log becomes buried in mud and water. Gradually over time the dissolved minerals in the
water replace the minerals in the wood and the wood becomes silicified (turns to stone).
When a tree falls down, sometimes it is covered by dirt and sand (sediment) that contains minerals.
When it rains, some of the minerals can dissolve and go down into the fallen tree. If the minerals
dry out in the log (become solid minerals again) and the wood pulp disappears, then that part of the
log becomes rock. If lots of wood pores get replaced by minerals, petrified wood
forms. If you look closely at some pieces, you can see pores and rings preserved from the original
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Update: June 2012