Once a tree falls in a forest- regardless if anyone is around to hear it- it has a chance to undergo a unique preservation process- Petrification. If the circumstances are just right, petrification occurs when the plant material is slowly replaced with minerals, usually a form of Silica like Chalcedony, Opal, or Quartz. Unlike other plant fossils, petrified wood is a three dimensional representation of organic vegetation in the fossil record. The organic cells are slowly, one by one, replaced with minerals- the slow process can allow the petrified wood to retain its tree rings, woodgrain, and bark pattern. In order to petrify, it needs a zero oxygen environment so the wood doesn’t rot away before it can fossilize.