The Petrified Forest

(Weds. January 6, 2010)


esterday we were in Silver City and Mogollon, New Mexico. Today we're next door in Arizona, driving  through the Petrified Forest National Park. It's hard to believe that about 225 millions ago during the late Triassic this high dry tableland was once a floodplain with many streams and swamps, where crocodile-like reptiles, giant fish eating amphibians, and small dinosaurs lived among a variety of ferns, cycads, and other plants and animals became the fossils we're looking at today. The tall, stately pine-like  trees (Araucarioxylon, Woodworthia and Schilderia) that grew along the headwaters, fell and were washed by swollen streams into the floodplain. There they were covered by silt, mud, and volcanic ash, and this blanket of deposits cut off oxygen and slowed the logs' decay. Gradually silica-bearing ground waters seeped through the logs, bit by bit, encased the original wood tissues with silica deposits. Slowly the process continued, the silica crystallized into the mineral quartz, and the logs were preserved as petrified wood.

After that time, the area sank, was flooded, and was covered with freshwater sediments. Then the area was lifted far above sea level, creating stress that cracked the giant logs. During recent geological time, wind and water wore away accumulated layers of hardened sediments. The erosion exposed the petrified logs,  fossilized animals, plants and sculpted desert in its present form.


Trees that turned into beautiful jewel-like stone.

We stopped at the park's museum. Mel's hoping I'll hurry up.

Inside there are strange prehistoric critter fossils...and replicas.

This is a replica of the original at the University of California.

Out back you can hike through the petrified remains of the ancient forest. After the walk we watched a movie we later purchased along with a couple of books to share with the kids. Here's a wonderful video that gives a better view of what you see in the park.

The petrified bridge.

This petroglyphed rock is named the "newspaper."

Thousands of prehistoric petroglyph sites are scattered throughout the southwestern U.S. on cliffs, boulders and cave walls. These images are composed of petroglyphs (rock carvings) and pictographs (rock paintings). For the vast majority of sites, the meanings and functions of these drawings have been lost. Some believe that many of these sites were used as "solar calendars" to track the yearly movement of the sun across the sky through the interplay of sunlight on the petroglyph. As long as time has not altered the alignments or surfaces of the rocks involved, these solar calendars function the same today as they did when they were created almost a thousand years ago.

The boss is enjoying a snack.

Couldn't resist adding an alien visitor over the Painted Desert. Trouble is, I don't know where it'll show up later.

We'd been told that there was a good restaurant at the northern entrance where we would be would be leaving the park, so that's where we had lunch. It was a wonderful educational experience. According to scientific theory, the ancient world of the giant creatures appeared mysteriously millions of years ago, was destroyed and replaced by the entirely new world we inhabit today. What a journey through time this has been.