Photography Now & Then #80
March 21st – and trees are still largely bare of leaves. I expect that two weeks from now, most trees and shrubs will be well along their way on leafing out for the year.
Now: First full day of spring, by astronomical reckoning, west-central Arkansas, March 21, 2018 (Apple iPhone 6s)
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Petrified Forest National Park’s Long Logs trail has one of largest concentrations of petrified wood in the park.
Then: Long Logs trail through ancient trees of stone, Petrified Forest National Park, Arizona, October 9, 2011 (Pentax K-r)
The Long Logs Trail (Protrails.com) circles one of the greatest concentrations of intact petrified logs in the Park. Trees over 100′ long were stripped of their branches by ancient rivers and eventually came together within this vicinity.
225 million years ago, Petrified Forest National Park lay within a heavily wooded, tropical floodplain. Large coniferous trees – felled by age, wind, disease or insects – were swept downstream, eventually settling in and around riverbeds that once rushed through the Park.
Period flooding and erosion interspersed with volcanic activity from the south and west carried sediments and ash downstream, settling over fallen trees in the area. In some cases trees were buried quickly and deeply enough to deprive them of oxygen, thus significantly slowing the natural decomposition process.Over time, ground water dissolved silica from volcanic ash into the porous body of fallen, buried trees. This solution formed quartz crystals that filled hollows and cracks in the logs, eventually ‘petrifying’ them by encasing and replacing the trees’ organic material with minerals.
The wood’s brilliant colors come from impurities in the quartz, such as iron, carbon, and manganese.
Photography Now & Then Notes:
- Series Photos
- The Now photo is one that is almost always taken the day of the blog post. In some instances, posts may be backdated if internet access is not available on the day of the photo or other reasons prevent posting Photography Now and Then.
- The Then photo is usually a randomly selected older photograph from a batch of photos specifically “curated” for Photography Now and Then.
- Each photo in this series is an “original work” – a copyright term – of Michael Goad.
- Reference links were accessed on the date the blog post was published, unless otherwise stated.
- The title convention for Photography Now & Then blog posts evolved early on from one word related to each photo separated by “&” to usually being the first word in the caption description for each photo.
