This was our first visit to the Petrified Forrest National Park and we were completely surprised and astounded by the colours within the Petrified Tree Logs, which are really fossils.
The trees grew in a climate similar to Costa Rica’s before the tectonic plates split up. Some 200 million years ago they were washed into a river system and quickly buried by massive amounts of sediment, thereby cutting them off from a water supply and greatly slowing down their decay.
The colours came from minerals that were contained in the water that penetrated the buried trees and created large crystals of clear quartz, purple amethyst, yellow citrine, and smoky quartz. These crystals were formed within the trees’ cellular structure over the millennia preserving that structure, which is easily seen today.
The petrified trees are now formed of very hard but brittle crystal structures.
We did notice that often the logs were surrounded by red crystals which appear to have been created in the bark of the original tree.
Should this be the case, some were quite thick layers of bark, something like the Sequoia trees of today.
The images showing the colours in the petrified wood were taken on the trail behind the Visitor Center and on the Crystal Forest trail.
However, on the Long Logs trail there were very few examples of the brightly coloured crystals and the logs were predominantly brown and black. Presumably a different water supply which did not contain the minerals that had created the bright colours elsewhere.
Given how long these Petrified Logs have been exposed, it came as a surprise that lichens and other flora appear to have difficulty colonizing the logs, but there are traces of this as seen below.
The crystals are very reflective of light, so these images were taken using a polarizing filter to reduce the reflective glare. The filter also tends to increase the saturation of the colours a little.
Gear: Nikon D800, Nikon GP-1, Nikon MB-D12, Nikkor 80.0-400.0mm f/4.5-5.6 VRIII, Nikon 77mm Thin Polarizing Filter, Lexar Digital Film