Not Arches
This photograph was one of those that come when you remember to turn around and look the other way.
These formations may have been arches that have collapsed due to sculpting by wind and water for centuries. These are in the Windows Section of Arches National Park. It is in the Windows Section of Arches National Park.The LaSal Mountains are visible in the distance between the formations.
Arches National park lies above an underground salt bed, which is the main cause of the formation of the arches, spires, balanced rocks, sandstone fins, and eroded monoliths in the area. This salt bed is thousands of feet thick in places, and was deposited in the Paradox Basin of the Colorado Plateau some 300 million years ago when a sea flowed into the region and eventually evaporated. Over millions of years, the salt bed was covered with debris eroded from the Uncompahgre Uplift to the northeast. During the Early Jurassic (about 210 Ma) desert conditions prevailed in the region and the vast Navajo Sandstone was deposited. An additional sequence of stream laid and windblown sediments, the Entrada Sandstone (about 140 Ma), was deposited on top of the Navajo. Over 5000 feet (1500 m) of younger sediments were deposited and have been mostly eroded away. Remnants of the cover exist in the area including exposures of the Cretaceous Mancos Shale.
the major formations visible in the park today are the salmon-colored Entrada Sandstone, in which most of the arches form, and the buff-colored Navajo Sandstone. These are visible in layer cake fashion throughout most of the park. Over time water seeped into the superficial cracks, joints and folds of these layers. Ice formed in the fissures, expanding and putting pressure on surrounding rock, breaking off bits and pieces.
Not Arches
This photograph was one of those that come when you remember to turn around and look the other way.
These formations may have been arches that have collapsed due to sculpting by wind and water for centuries. These are in the Windows Section of Arches National Park. It is in the Windows Section of Arches National Park.The LaSal Mountains are visible in the distance between the formations.
Arches National park lies above an underground salt bed, which is the main cause of the formation of the arches, spires, balanced rocks, sandstone fins, and eroded monoliths in the area. This salt bed is thousands of feet thick in places, and was deposited in the Paradox Basin of the Colorado Plateau some 300 million years ago when a sea flowed into the region and eventually evaporated. Over millions of years, the salt bed was covered with debris eroded from the Uncompahgre Uplift to the northeast. During the Early Jurassic (about 210 Ma) desert conditions prevailed in the region and the vast Navajo Sandstone was deposited. An additional sequence of stream laid and windblown sediments, the Entrada Sandstone (about 140 Ma), was deposited on top of the Navajo. Over 5000 feet (1500 m) of younger sediments were deposited and have been mostly eroded away. Remnants of the cover exist in the area including exposures of the Cretaceous Mancos Shale.
the major formations visible in the park today are the salmon-colored Entrada Sandstone, in which most of the arches form, and the buff-colored Navajo Sandstone. These are visible in layer cake fashion throughout most of the park. Over time water seeped into the superficial cracks, joints and folds of these layers. Ice formed in the fissures, expanding and putting pressure on surrounding rock, breaking off bits and pieces.