Happy birthday to Petrified Forest National Park!
The park was originally established as Petrified Forest National Monument in 1906, and was upgraded to a National Park on this day in 1962.
Home to one of the largest and most colorful concentrations of petrified wood in the world, this park is like no other in the American Southwest. The photo above shows hunks of petrified wood from my visit to the park in October 2016.
I’m sure many of you are wondering, how do we get petrified wood? Say no more!
The trees that became petrified here lived about 225 million years ago during the Late Triassic period. During that time period, the climate here was much wetter and the elevation much lower — a similar ecosystem to the present day Mississippi River Delta.
Similar, except for the volcanoes. Volcanic ash blanketed the forest, and explosive eruptions knocked over trees, which fell into the mud of swamps, marshes, and rivers. The ash coating prevented the trees from decaying, and over time, minerals like silica seeped into the wood, replacing the organic matter of the wood with quartz tinted with trace amounts of minerals.
These trace minerals, like iron and manganese also seeped in from surrounding sediment, and create the striking patterns and hues seen in petrified wood.
So petrified wood is not actually wood, but rock that used to be wood — with the original patterns of the wood preserved in stone.
The layers of mud surrounding the trees also solidified into rock, obviously named mudstone. Of course, mudstone is a very soft rock, whereas the quartz-based petrified wood is very hard.
This is important because between 70 and 40 million years ago, the mudstone containing the petrified wood — known as the Chinle Formation — was lifted 5,000 vertical feet when the Colorado Plateau was formed.
The now high elevation and isolated location far oceans now makes the region a harsh, semi-arid environment. And over time, erosion slowly eats away at the rocks of the Plateau. As the wind and rain carved through the Chinle Formation, the forces ate away the soft mudstone much faster than the hard petrified wood, leaving the specimens to appear strewn about the high desert.
And such is how we see the Petrified Forest today — which, in my opinion — is one of our most underrated National Parks. If you decide to visit, be sure to triple check the weather forecast. Its sometimes scorching, other times frigid, and if you’re lucky somewhere in between. But its almost always dry and windy so be sure to bring your Chap Stick.
That’s it for today’s Daily Dose. I hope your day is as colorful as a piece of petrified wood.
-Jake
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