How old is petrified forest national park
With their distinctive elegant fluting, the projectile points of these ancient people help define the Clovis and Folsom Cultures. Folsom and Clovis camps have been found within Petrified Forest National Park as well as fluted projectile points made of petrified wood. By B. The area became warmer and the monsoon pattern of precipitation evolved.
The megafauna of the past were extinct. People had to broaden their source of food, including many different species of plants and animals. Farming and sedentism began during this period, particularly as corn was brought into the region from the south in the Late Archaic Period. Indicative of this period were one-handed manos, basin metates, flaked tools, and no pottery.
Routes continued to be explored after the Southwest became part of U. Army Lt. Amiel Whipple, surveying for a route along the 35th Parallel passed down a broad sandy wash in the red badlands of the Painted Desert. Much of the Petrified Forest formed from tall trees called conifers. They grew over million years ago near waterways.
During floods, water forced the trees to be pulled up from the ground. Over time, the wood from the trees became petrified. It sits within the Painted Desert. Brilliantly colored mudstones and clays cover the land as far as the eye can see. They contain bentonite, a clay that is the product of changed volcanic ash. The oldest geological formations in the park are about million years old. Differently colored formations show different time periods.
The Blue Mesa formations, for example, have thick bands of grey, purple, blue and green mudstones. They are about million years old. People first came here after the last Ice Age. Early Paleoindian groups used the petrified wood to create different kinds of stone tools. They used them to hunt large animals. The climate warmed over several thousand years. Humans began building villages here and growing food, such as corn, squash and beans. In the s, people in the area began building above-ground houses, called pueblos.
They also made pottery for cooking and other uses. The park consists of two main sections, and recent legislation has authorized doubling the land area to , acres. Located in the south are the major concentrations of the famous colorful petrified wood; in the north rise the colorful banded badlands of the Painted Desert. Giant fossilized logs, many of them fractured into cord-wood-size segments, lie scattered throughout, like headstones bearing a deceased's likeness. Much of the quartz that replaced the wood tissue million years ago is tinted in rainbow hues.
Many visitors cannot resist taking rocks, despite strict regulations and stiff fines against removing any material. To see if the petrified wood was actually disappearing at an alarming rate, resource managers established survey plots with a specific number of pieces of wood; some were nearly barren in less than a week. The problem is not new. Military survey parties passing through the region in the s filled their saddlebags with the petrified wood.
As word of these remarkable deposits spread, fossil logs were hauled off by the wagonload for tabletops, lamps, and mantels. In the s gem collectors began dynamiting logs searching for amethyst and quartz crystals. To prevent further destruction of its unique bounty, the area was designated a national monument in and a national park more than a half century later.
If you are traveling west on I, exit into park. When leaving the south end of park, the road joins US Follow US for 19 miles to Holbrook and back to I If you are traveling east on I, take the US exit in Holbrook. The south entrance is 19 miles farther. After driving through the park, leave via I Airport: Flagstaff. Nature produced the mineralized wood under very special circumstances.
The trees were uprooted by great floods or perhaps flows of lava, then washed down from the highlands and buried by silt and volcanic ash. Water seeping through the wood replaced decaying organic material cell by cell with multicolored silica. Eventually, the land where the great logs were buried was lifted up by geological upheaval, and wind and rain began to wear away the overlying sediments, finally exposing the long-buried, now petrified wood. Each piece of wood is unique, burning with the colors of the Painted Desert, of which Petrified Forest National Park is a part.
Some of the great trunks still bear the annual rings that reveal their life histories in prehistoric times. The Paiute believed that the petrified logs were the great arrow shafts of their thunder god, Shinauv.
The Navajo said they were the bones of a mythological giant, called Yietso.
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