Sunday, October 22, 2017

The Hawthornes Visit The Petrified Forest National Park And The Painted Desert.

The Hawthornes are merrily on their way
to the Petrified Forest National Park,
located near the southern edge of the Colorado Plateau,
between I40 (Route 66 sorta) and Hwy 180,
2-3 hours southeast of the Grand Canyon.
We're running along at a 70 mph clip
so keep up with the pics.

And here's my first view of the Painted Desert.
The Painted Desert encompasses over 93,500 acres
and stretches over 160 miles from the southeastern rim
 of the Grand Canyon to the Petrified Forest.

Its name derives from its multitude of colors
ranging from lavenders, grays, reds, oranges, and pinks.
The Painted Desert is a landscape of rainbow colors.
The Painted Desert is just the start of our 28 mile drive
throughout the Petrified Forest.
At this particular lookout, we're seeing only a small potion of the Painted Desert.  It extends over 7500 square miles across northeastern Arizona and the Petrified Forest National Park lies at its heart.  The entire park contains the colorful rocks of the Painted Desert.

These particular mudstone and sandstone rocks are called the Chinle Formation and were deposited from 227 to 205 million years ago during the Late Triassic Period.  During that time, the supercontinent Pangaea broke apart, eventually forming our present continents.  Over the next 10 million years, the rocks of the Chinle Formation were deeply buried, uplifted, and eroded into the badland topography you see today.  Approximately 20 million years of Late Triassic rock and fossil history are recorded in this geologic kaleidoscope.
The Painted Desert is about 120 miles long by 60 miles wide and includes all of Petrified Forest National Park.
Ancient Arizona.  Hot.  Humid.  Lush.  Green.  During the Triassic Period, 1225 million years ago, this was a tropical landscape with abundant vegetation - ferns, horsetails, and cycads.  Early dinosaurs and reptiles roamed; fish, clams, snails, and crayfish moved through rivers; and giant 180-foot conifers reached to the skies.

Over the past 200 million years continents moved, regions uplifted, climate changed, and the river system, along with its plants and animals, was buried by layers of sediment.  Wind and water have continually molded, sculpted, and peeled back these layers, giving us a glimpse of the once tropical land we know today as Arizona.
The Chinle Formation consists mainly of sandstone and mudstone layers which were deposited by a vast river in a forest ecosystem.  Geologists group these layers into members, which together make up the formation.  Older members are at the bottom..., with youngest at the top.

All the colors you see are caused by the iron in the sediments.  During deposition, drier climates allow the minerals to be exposed to oxygen, rusting the iron and creating red, brown, and orange colors.  Wetter climates can drown the sediments, allowing little or no contact with oxygen, causing the layers to be blue, gray, and purple.

Below lies a black basalt which forms the rim of the plateau on which I'm standing.  This hard basalt, called the Bidahochi Formation, was deposited by local volcanoes between 16 and 5 million years ago, and forms a protective cap over the soft, red rocks of the much older Chinle Formation.  The Bidahochi basalt shelters this area from the effects of weather like an umbrella, while the rest of the desert is left exposed and vulnerable to erosion, carving the badland topography you see today.

Pilot Rock is in the background.
Elevation: 6234 ft.
Distance: 6.6 miles

Right center is the Lithodendren Wash
at a distance of 1 mile.

Pilot Rock.

Another view of Pilot Rock.

The Petrified Forest is part of a natural travel corridor that has been used for over 10,000 years.  It offers a rich story of travelers, traders, and migrants passing near this location through the centuries.  This natural corridor skirts the Rocky Mountains and other adverse terrain providing a direct route between the eastern and western United States.  For over 13,000 years, people, including Ice Age hunters, Spanish explorers, military and railroad expeditions, and automobile drivers, favored this path of least resistance.

Petrified Forest is the only National Park in the country with a portion of Historic Route 66 within its boundaries. ...  This stretch of Route 66 was open from 1926 until 1958 and it was the primary way millions of travelers initially experienced Petrified Forest and the Painted Desert.

During the Triassic Era all the continents were joined together as one landmass called Pangea.  Since that time they have scattered across the globe.  Now our continents are joined together again by our intricate trade routes.  Humans are spreading plants, animals, and diseases from one continent to another at a rate unobserved for millions of years.  

Though trade routes are vital for our economic well-being, they are influence the health of native species even in remote places like Petrified Forest National Park.  Roads, rails, and flight routes accelerate the spread of exotic species while at the same time they hinder the movement of native animals trying to migrate and adapt to changing climate.

The village on the Rio Puerco (Puerco Pueblo) is a prehistoric settlement built of shaped sandstone blocks by ancestral Puebloan people.  It was inhabited between AD 1250 and 1380.  At its peak, the pueblo had over 100 rooms, with a possible population of 200 people.  During the village's occupation, fields of corn, beans, and squash sustained by the summer rains would have filled the river's floodplain.

Puerco Pueblo was not isolated in space or time.  The river provided a travel corridor across the grasslands of the Colorado Plateau.  Large and small communities existed up and downt he Rio Puerco and Little Colorado River.  Puerco Pueblo would have been visited by travelers and traders from far outside the ancestral Puebloan cultural area who brought different types of pottery and goods, as well as new ideas to the residents of Puerco.

Archeologists have excavated only about a third of the site, some of which has been backfilled to preserve the fragile remnants of walls and floor features.

Over 100 rooms formed a one-story apartment complex surrounding a central plaza in the village.  The building materials for the pueblo were blocks of native sandstone, shaped by hand, and mortared together with mud.  The exterior and interior walls were finished with plaster.

The structures above ground served as living quarters and storage rooms.  There were also several subterranean rooms, or kivas.  Kivas are ceremonial and religious structures.  These likely had flat roofs with a square entrance above a hearth.  As the smoke rose through the entrance, fresh air was drawn through a small ventilation shaft.

Jasper Forest contains one of the largest accumulations of petrified wood in the world.  By the late 1800s, interest in petrified wood was threatening this landscape.  In 1895, the Arizona Territorial legislature petitioned Congress to protect this valuable scientific and cultural treasure.  In 1906, President Theodore Roosevelt signed legislation creating Petrified Forest National Monument.  The monument became a national park in 1962.

End of a petrified log.

Next stop -  The Grand Canyon.

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