Petrified Forest National Park Favorite Tips by toonsarah Top 5 Page for this destination

Some geology

Favorite thing: The trees that created the now petrified logs grew in an ancient period in geologic history, called the Triassic, and were of the species named Araucariaxylon arizonicum. Around 200 million years ago, volcanic activity caused many trees to fall, and the fallen logs were washed into a river and buried quickly (faster than they could decompose) and deeply by sediment. This sealed them from oxygen and slowed their decay. The levels of volcanic ash in the sediment created silica, and over time this replaced the logs’ fibrous organic material and crystallized, forming a core of quartz. Other elements are present in smaller quantities, such as magnesium, copper, iron and zinc, and also semi-precious gems such as amethyst and citrine.

The upper layers of sediment have been eroded away over time, exposing the now petrified trees. Some of them are as large as 100 feet by 6 feet in diameter. They are multi-coloured and, because of the quartz in particular, glitter in the sun. The different colours are caused by different minerals – for instance, iron gives many their orange and red tones, which magnesium has turned other blue or purple.

Wildlife

Favorite thing: As you would expect in this desert environment, the park is home to a number of reptiles, both snakes and lizards. The former include rattlesnakes, so be careful – keep to the paths and make a noise if you do walk through any undergrowth. We heard the distinctive rattle a couple of times but saw no snakes at all. We did however spot this beauty of a lizard, which I think from checking a few websites must be a collared lizard. These are native to much of the central and south western United States, as well as to northern Mexico. They like rocky areas with sparse vegetation, so the Petrified Forest must be a perfect home for them. It gets its name from the black bands behind its head, clearly visible on my photo.