Monday, November 6, 2017

The Hawthornes Travel Utah.

Sights across Utah.
At 80mph.

 This is Castle Valley.  In the 1870s, the Mormon Settlers came east across the Wasatch Plateau to the high mountain deserts of Castle Valley and the San Rafael Swell.  It was the last place Mormon colonizer Brigham Young called his people to settle.  They were seeking new grazing lands for their livestock but found little of the lush pastureland they had been accustomed to in the Sanpete Valley.  Indians warned them not to come because the water was bad and had killed their women.  Good or bad, water was so scarce, life here was harsh.  The toughest of the desert cowboys and outlaws survived because they knew where every water hole and spring was hidden in the rocks and canons.  A few built livestock ponds and made a living here.

The layers of the San Rafael Swell dip to the east.  The descent is dizzying.  The great cliff-capped hills in front are the inward side or underbelly of the huge rock flat irons that make up the jagged steps of the San Rafael Reef.  The Reef forms the steep eastern edge of the Swell anticline.  The solidly cemented, hard-to-erode Navajo Sandstone crowns the flat irons with cliffs over 200 feet high.  The underlying Kayenta Formation, made of stream channel sandstones and less solidly cemented shales and siltstones, is much easier to erode, so it forms a slope rather than a cliff.  The dark red cliffs below it mark the presence of the well-cemented Wingate Sandstone.  These layers were deposited during the Triassic Period.  This is the typical red rock of the Colorado Plateau.  The red color is due to the presence of iron oxide.  The depth of color depends on the amount of iron oxide in the sands and the extent of oxidation.  Water has sliced and sculpted stunning narrow canyons and formations in the sandstone.

They call it the San Rafael Reef, a 30-mile long stone barrier, a sawtooth ridge at the eastern edge of nowhere.  For centuries, only the most intrepid travelers found their way through its narrow slot canyons and on to the Green River crossing.  The early Spanish explorers detoured 20 miles north to avoid the forbidding wall.  In 1883, the Denver and Rio Grand Railroad also avoided breaching the Reef, laying track just east of its sheer walls, north to Salt Lake City.  In 1957, the decision was made to increase the nation's interstate highway system and I-70 was engineered to bisect the San Rafael Swell.  At Spotted Wolf Canyon, workers could stand and touch both walls of the canyon before construction began in October 1967.  Engineers and surveyors used body harnesses and ropes to work as high as 400 feet above the canyon floor.  Crews excavated 3.5 million cubic yards of rock from the area at a cost of $4.5 million for eight miles of road.  On November 5, 1970, the Utah Department of Transportation opened the 70-mile section from Fremont Junction to Green River for 2-lane traffic.  Two more lanes were added in the 1980s.

Next - Arches National Park.

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