In the last post, we were stuck in a wayward time machine, emerging in a nightmarish swamp and river floodplain populated by strange and frightening reptiles and other creatures. I asked for help in explaining where and when we were, and the readers responded quickly and accurately (strangely enough, a bunch of readers share the same name: Anonymous!). We had landed in the Triassic Period, about 225 million years ago, in Petrified Forest National Park, Arizona.
Amiel Whipple and geologist Jules Marcou, during explorations in the early 1850s (discovered by Europeans, anyway; there are ruins in the park made hundreds of years ago out of petrified wood!).
Once the railroad was constructed, travelers began to visit the area, and many removed huge amounts of petrified wood. There was even a business at one time that was prepared to ground up the "wood" for use as an abrasive. Local people began to fear that the precious mineral would disappear, and they began efforts to establish a national park to protect the resource. The first effort failed in 1895, but the passage of the National Antiquities Act in 1906 led to the proclamation of Petrified Forest National Monument the same year (Congress can establish parks, but the President can proclaim national monuments). It wasn't until 1962 that Congress established the area as a national park. In 2004, the size of the park was more than doubled, to 341 square miles (884 square kilometers). Despite the legal protection, it is estimated that tons of petrified wood are stolen every year. This, despite hefty fines and the easy availability of petrified wood outside the park boundaries.
Araucarioxylon arizonicum is the most common, and as such has been designated as Arizona's state fossil.
Chindesaurus bryansmalli, a small carnivorous dinosaur found for the first time at Petrified Forest.
The protection of the park has revealed another important resource. The explorations of the 1850s were hardly the first incursion of humans into the region. The presence of a secure source of water (the Puerco River) and a prairie environment populated by numerous grazing animals meant that people have lived in the region since the end of the last ice age 13,000 years ago. The park preserves hundreds of archaeological sites, including the ruins of entire villages.