Perched high above the Colorado River, the park is part of southern Utah's extended canyon country, carved and shaped by eons of weathering and erosion. Some million years ago, inland seas covered the large basin that formed this region.
The seas refilled and evaporated—29 times in all—leaving behind salt beds thousands of feet thick. Later, sand and boulders carried down by streams from the uplands eventually buried the salt beds beneath thick layers of stone. Because the salt layer is less dense than the overlying blanket of rock, it rises up through it, forming it into domes and ridges, with valleys in between.
Most of the formations at Arches are made of soft red sandstone deposited million years ago. Much later, groundwater began to dissolve the underlying salt deposits. The sandstone domes collapsed and weathered into a maze of vertical rock slabs called "fins. The land has a timeless, indestructible look that is misleading. More than , visitors each year threaten the fragile high desert ecosystem.
One concern is a dark scale called biological soil crust composed of cyanobacteria, algae, fungi, and lichens that grow in sandy areas in the park. Footprints tracked across this living community may remain visible for years. In fact, the aridity helps preserve traces of past activity for centuries. Visitors are asked to walk only on designated trails or stay on slickrock or wash bottoms.
There are more than 2, arches in the park; to be classified as an arch, the opening must measure at least three feet across. The largest arch in the park, Landscape Arch, spans feet longer than a football field base to base. New arches are constantly forming, while old ones occasionally collapse—most recently Wall Arch, which fell in Arches National Park contains ephemeral pools, from a few inches to several feet in depth, that are essentially mini-ecosystems, home to tadpoles, fairy shrimp, and insects.
The pools form among the sandstone basins, within potholes that collect the rare rainwater and sediment. About million years ago an inland sea covered what is now Arches National Park. The sea evaporated and re-formed more than 29 times, leaving behind salt beds thousands of feet thick. One of the most famous arches in the park is Delicate Arch.
This arch has become widely recognized as a symbol of Utah, appearing on a U. Postage stamp and the state license plates. This sandstone formation stands alone, unlike most arches in the park. The largest natural arch is Landscape Arch, which is a thin ribbon of rock spanning feet in length. Other features of the park include Fiery Furnace, which is a collection of narrow rock canyons.
There are also tall sandstone fins and columns such as The Organ and the Courthouse Towers. All of these structures make up an impressive landscape on the Colorado Plateau.
The park's desert location can make it a difficult place to hike in the summer sun. It often reaches over degrees, dropping quickly into the 60s at night.
The winter is the least visited time at Arches National Park , as the temperature falls dramatically in these months. There is an occasional light dusting of snow over the area, which only adds to its unique coloring contrasts. There is a lot of plant life throughout the park such as prickly pear cacti, moss, Utah juniper, pinyon pine, and various grasses.
As the subsurface movement of salt shaped the surface, erosion stripped away the younger rock layers. Water seeped into cracks and joints, washing away loose debris and eroding the "cement" that held the sandstone together, leaving a series of free-standing fins. During colder periods, ice formed, its expansion putting pressure on the rock, breaking off bits and pieces, and sometimes creating openings.
Many damaged fins collapsed. Others, with the right degree of hardness and balance, have survived as the world famous formations of Arches National Park. We're just the latest batch of humans to be amazed by Arches.
Human history in the park goes back at least 10, years, to when hunter-gatherers came to today's Courthouse Wash to find rocks and stones suitable for working into tools and weapons.
His weathered cabin still stands there, albeit it a little worse for the wear. Things didn't really start happening for Arches as a national icon until the s, when Alexander Ringhoffer, a prospector, wrote the Rio Grande Western Railroad in in an effort to publicize the area and gain support for creating a national park. And, of course, the late Edward Abbey got his taste of Park Service life as a seasonal ranger at Arches in the s. During that stint, Abbey discovered the soul of the red-rock landscape and proceeded to warn of its downfall if development wasn't halted and more land wasn't preserved unscathed.
Skip to main content.
0コメント