Learn about Petrified Wood

There are two principal ways that trees become fossilized into petrified wood. 

Volcanic activity can quickly kill and bury entire forests with silica ash. As well, trees that are killed by flooding or drowning and become submerged in the sediments can over millions of years and under the right conditions of pH and temperature transform into fossils. This happens through the processes of permineralization and petrifaction (mineral replacement).

Water, saturated in minerals such as silica and iron oxides, soaks and permeates into the porous tissues of wood and the minerals in solution precipitate using the cell walls as a template. Later after longer time periods, the minerals fill in the cells and connecting areas.

The striking array of colours of petrified wood are due to the kinds of minerals that are deposited from the surround mud and water. White coloured petrified wood is due to a high level of silicon dioxide. Green and blue colours are created by copper and manganese. The bright red colours of the petrified forests of Arizona are due to high levels of iron.