The geology of the park is the consequence of deposition, uplift and erosion. Island in the Sky is a mesa overlooking the Green River (Colorado River tributary) to the west and the Colorado River to the east, and separated from the Colorado Plateau by "the neck". From the top of the mesa to the Honaker Trail Formation at the canyon river bottom, 150 million years of geologic stratum is exposed. Upheaval Dome consists of the Chinle Formation in the center and the Navajo Sandstone along the rim. The Cedar Mesa Sandstone comprised the Needles District. Canyons comprise the Maze District. [1] [2]
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The exposed geology of the Canyonlands area is complex and diverse; 12 formations are exposed in Canyonlands National Park that range in age from Pennsylvanian to Cretaceous. The oldest and perhaps most interesting was created from evaporites deposited from evaporating seawater. Various fossil-rich limestones, sandstones, and shales were deposited by advancing and retreating warm shallow seas through much of the remaining Paleozoic.
Eroded sediment from a nearby mountain range later mixed with coastal dune and sand bar deposits. The end of the Paleozoic and the start of the Mesozoic saw the seas retreat from the region until the late Cenozoic. A subdued topography was dominated by flood plains and tidal flats. Now much further inland, the Triassic climate in the region was dry. Vast deserts covered much of that part of North America, except for one period when streams for a time fought the sand dunes. Wetter times returned in the Cretaceous as the area was flooded by the Western Interior Seaway.
The uplifting of the Rocky Mountains starting in late Cretaceous - greatly affected the Canyonlands region. Erosion rates increased and further quickened the onset of the ice ages in the Pleistocene. Modern-day erosion occurs at a slower rate.
A vast sea covered the region in early Pennsylvanian time. A basin in the area called Paradox Basin subsided and a mountain range called the Uncompahgre Mountains was uplifted to the east. Great quantities of seawater were trapped in the subsiding basin and water became increasingly saline in the hot and dry climate. Thousands of feet of evaporites (anhydrite and gypsum then halite) started to build up in the Mid Pennsylvanian and storms occasionally washed sediment from the nearby mountains. Fresh seawater periodically refilled the basin but was never able to flush out the very salty water there (the new water in fact floated on top of the brine). These beds were later lithified to become the Paradox Formation, which in turn is part of the Hermosa Group. Compressed salt beds from the Paradox started to flow plastically later in the Pennsylvanian and probably continued to move from then until the end of the Jurassic. Satellite-based measurements indicate that flow of salt and gypsum continues today to cause flexing and faulting of overlying sedimentary layers.
The Paradox is up to 5000 feet (1520 m) thick in places and in the park is exposed at the bottom of Cataract Canyon as rock gypsum inter-bedded with black shale. Upward movement of the Paradox is also a possible theory for the creation of Upheaval Dome, although none of the Paradox is exposed on the dome, the predominant theory being a meteor crater.
A warm shallow sea again flooded the region near the end of the Pennsylvanian. Limey oozes, sand, and mud were deposited on top of the salt-filled basin. These sediments became the fossil-rich limestones, sandstones, and shales of the gray-colored Honaker Trail Formation. Outcrops of the Honaker Trail can be seen near the bottom of deep canyons in the park, most notably along the Colorado River.
A period of erosion then ensued, creating a break in the geologic record called an unconformity.
Early in the Permian a transgressing (advancing) sea laid down the Halgaito Shale. Coastal lowlands returned to the area after the sea regressed (retreated), forming the Elephant Canyon Formation. These formations can now be seen in Cataract and Elephant Canyons.
The Uncompahgre Mountains (Uncompahgre Plateau) were undergoing extensive erosion during this time. Large alluvial fans filled the basin where it met the range. The resulting Cutler red beds are made of iron-rich arkose sandstone. Underwater sand bars and sand dunes on the coast inter-fingered with the red beds and later became the white-colored cliff-forming Cedar Mesa Sandstone. Today these two competing rock units are exposed in a 4 to 5 mile (6.4 to 8 km) wide belt across the park, stretching from south of the Needles through the Maze and to the Elaterite Basin.
Brightly colored oxidized muds were deposited on top of the Cedar Mesa and ranged in color from red to brown. These sediments eventually became the slope-forming Organ Rock Shale formation and can be seen in the Land of Standing Rocks part of the park.
Coastal sand dunes and marine sand bars once again became dominant, creating the cross-bedded cliff-forming White Rim Sandstone. It is exposed as a topographic bench 1200 feet (365 m) below the top of Island in the Sky (thus earning its name) and along the White Rim Road. A fossilized offshore sand bar made of the White Cliff Sandstone is also exposed in the Elaterite Basin. A tarry dark-brown oil called elaterite seeps out of the structure, giving the basin its name.
The Permian sea retreated, which exposed the land to a long period of erosion and thus created a second unconformity.
Clastic red beds were laid down in shallow-water on top of the eroded Paleozoic surface early in the Triassic. These sediments were deposited on flood plains by streams on an expansive lowland that was slightly sloped in the direction of an ocean to the west. Mud built up in tidal flats to become the mudstone of Moenkopi Formation. Examples of this formation, some that still show fossilized ripple marks and mudcracks, can be seen in the northern and western parts of the park.
Another period of erosion returned, creating a third unconformity. The brightly colored shales of the slope-forming Chinle Formation were laid down on top of this eroded surface. Petrified wood from the Petrified Forest Member of the Chinle is sometimes found at the base of Chinle slopes.
The Glen Canyon Group of formations includes (from oldest - lowest - to youngest) the
These formations are most prominently exposed in the western and northern sections of the park.
Triassic climates progressively became dryer, prompting the formation of sand dunes that buried dry stream beds and their flood plain. This sand became the cliff-forming several hundred feet (many tens of meters) high and red-colored Windgate Sandstone. Outcrops tend to run for hundreds of miles (hundreds of kilometers) with few breaks, creating an impediment to human travel.
For a time climatic conditions became wetter and streams cut channels through the sand dunes. Reddish-brown to lavender-colored sandstones interbedded with siltstones and shales constitute the resulting ledgy slope-forming Kayenta Formation.
The youngest and therefore topmost formation in the Glen Canyon Group was formed after arid conditions returned to the region. A vast and very dry desert, not unlike the modern Sahara, covered 150,000 square miles (388,000 km2) of western North America. Cross bedded sand dunes accumulated to great thickness, especially in the nearby Zion and Kolob canyons area (see geology of the Zion and Kolob canyons area), forming the buff to pale orange Navajo Sandstone. Navajo outcrops form cliffs, temples, and under certain conditions natural arches (such as Millard Canyon Arch) in the area.
A fourth unconformity was created by a period of erosion.
Mud flats developed on top of the eroded surface of the Glen Canyon Group, forming the Carmel Formation. The massive cliff-forming Entrada Sandstone in turn was created on top of the Carmel. A long period of erosion stripped away most of the San Rafael Group in the area along with any formations that may have been laid down in the Cretaceous period.
Starting 70 million years ago and extending well into the Cenozoic, a mountain-building event called the Laramide orogeny uplifted the Rocky Mountains and with it the Canyonlands region. Even though the strata were uplifted thousands of feet (hundreds of meters) they were left at more-or-less the same horizontally. Uplift-associated-jointing did occur and has since influenced erosional patterns.
When ground water seeped into the salt beds of the Paradox Formation it carried away the topmost and more soluble salts, leaving gypsum. This process was so pronounced in ‘’The Grabens’’ that the overlying rock collapsed into voids left by escaping salt.
Increased precipitation during the ice ages of the Pleistocene quickened the rate of canyon excavation. Canyon widening and deepening was especially rapid for the gorges of the Green and Colorado Rivers, which were in part fed by glacier-melt from the Rocky Mountains. Alluvial-fan-creation-landslides and sand dune-migration were also accelerated in the Pleistocene. These processes continue to shape the Canyonlands landscape in the Holocene (the current epoch), but at a slower rate due to a significant increase in aridity.
Canyonlands National Park is a national park of the United States located in southeastern Utah near the town of Moab. The park preserves a colorful landscape eroded into numerous canyons, mesas, and buttes by the Colorado River, the Green River, and their respective tributaries. Legislation creating the park was signed into law by President Lyndon B. Johnson on September 12, 1964.
The geology of the Grand Canyon area includes one of the most complete and studied sequences of rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old. Most were deposited in warm, shallow seas and near ancient, long-gone sea shores in western North America. Both marine and terrestrial sediments are represented, including lithified sand dunes from an extinct desert. There are at least 14 known unconformities in the geologic record found in the Grand Canyon.
The geology of the Zion and Kolob canyons area includes nine known exposed formations, all visible in Zion National Park in the U.S. state of Utah. Together, these formations represent about 150 million years of mostly Mesozoic-aged sedimentation in that part of North America. Part of a super-sequence of rock units called the Grand Staircase, the formations exposed in the Zion and Kolob area were deposited in several different environments that range from the warm shallow seas of the Kaibab and Moenkopi formations, streams and lakes of the Chinle, Moenave, and Kayenta formations to the large deserts of the Navajo and Temple Cap formations and dry near shore environments of the Carmel Formation.
The exposed geology of the Bryce Canyon area in Utah shows a record of deposition that covers the last part of the Cretaceous Period and the first half of the Cenozoic era in that part of North America. The ancient depositional environment of the region around what is now Bryce Canyon National Park varied from the warm shallow sea in which the Dakota Sandstone and the Tropic Shale were deposited to the cool streams and lakes that contributed sediment to the colorful Claron Formation that dominates the park's amphitheaters.
The Colorado Plateau is a physiographic and desert region of the Intermontane Plateaus, roughly centered on the Four Corners region of the southwestern United States. This plateau covers an area of 336,700 km2 (130,000 mi2) within western Colorado, northwestern New Mexico, southern and eastern Utah, northern Arizona, and a tiny fraction in the extreme southeast of Nevada. About 90% of the area is drained by the Colorado River and its main tributaries: the Green, San Juan, and Little Colorado. Most of the remainder of the plateau is drained by the Rio Grande and its tributaries.
The geology of the Grand Teton area consists of some of the oldest rocks and one of the youngest mountain ranges in North America. The Teton Range, partly located in Grand Teton National Park, started to grow some 9 million years ago. An older feature, Jackson Hole, is a basin that sits aside the range.
The exposed geology of the Capitol Reef area presents a record of mostly Mesozoic-aged sedimentation in an area of North America in and around Capitol Reef National Park, on the Colorado Plateau in southeastern Utah.
The Delaware Basin is a geologic depositional and structural basin in West Texas and southern New Mexico, famous for holding large oil fields and for a fossilized reef exposed at the surface. Guadalupe Mountains National Park and Carlsbad Caverns National Park protect part of the basin. It is part of the larger Permian Basin, itself contained within the Mid-Continent oil province.
The Cutler Formation or Cutler Group is a rock unit that is exposed across the U.S. states of Arizona, northwest New Mexico, southeast Utah and southwest Colorado. It was laid down in the Early Permian during the Wolfcampian epoch.
The Moenkopi Formation is a geological formation that is spread across the U.S. states of New Mexico, northern Arizona, Nevada, southeastern California, eastern Utah and western Colorado. This unit is considered to be a group in Arizona. Part of the Colorado Plateau and Basin and Range, this red sandstone was laid down in the Lower Triassic and possibly part of the Middle Triassic, around 240 million years ago.
The San Juan Basin is a geologic structural basin located near the Four Corners region of the Southwestern United States. The basin covers 7,500 square miles and resides in northwestern New Mexico, southwestern Colorado, and parts of Utah and Arizona. Specifically, the basin occupies space in the San Juan, Rio Arriba, Sandoval, and McKinley counties in New Mexico, and La Plata and Archuleta counties in Colorado. The basin extends roughly 100 miles (160 km) N-S and 90 miles (140 km) E-W.
The geology of Kansas encompasses the geologic history and the presently exposed rock and soil. Rock that crops out in the US state of Kansas was formed during the Phanerozoic eon, which consists of three geologic eras: the Paleozoic, Mesozoic and Cenozoic. Paleozoic rocks at the surface in Kansas are primarily from the Mississippian, Pennsylvanian, and Permian periods.
Cedar Mesa Sandstone is a sandstone member of the Cutler Formation, found in southeast Utah, southwest Colorado, northwest New Mexico, and northeast Arizona.
In geology, the Paradox Formation Is a Pennsylvanian age formation which consists of abundant evaporites with lesser interbedded shale, sandstone, and limestone. The evaporites are largely composed of gypsum, anhydrite, and halite. The formation is found mostly in the subsurface, but there are scattered exposures in anticlines in eastern Utah and western Colorado. These surface exposures occur in the Black Mesa, San Juan and Paradox Basins and the formation is found in the subsurface in southwestern Colorado, southeastern Utah, northeastern Arizona and northeastern New Mexico.
The Unkar Group is a sequence of strata of Proterozoic age that are subdivided into five geologic formations and exposed within the Grand Canyon, Arizona, Southwestern United States. The Unkar Group is the basal formation of the Grand Canyon Supergroup. The Unkar is about 1,600 to 2,200 m thick and composed, in ascending order, of the Bass Formation, Hakatai Shale, Shinumo Quartzite, Dox Formation, and Cardenas Basalt. The Cardenas Basalt and Dox Formation are found mostly in the eastern region of Grand Canyon. The Shinumo Quartzite, Hakatai Shale, and Bass Formation are found in central Grand Canyon. The Unkar Group accumulated approximately between 1250 and 1104 Ma. In ascending order, the Unkar Group is overlain by the Nankoweap Formation, about 113 to 150 m thick; the Chuar Group, about 1,900 m (6,200 ft) thick; and the Sixtymile Formation, about 60 m (200 ft) thick. These are all of the units of the Grand Canyon Supergroup. The Unkar Group makes up approximately half of the thickness of the Grand Canyon Supergroup.
The Supai Group is a slope-forming section of red bed deposits found in the Colorado Plateau. The group was laid down during the Pennsylvanian to Lower Permian. Cliff-forming interbeds of sandstone are noticeable throughout the group. The Supai Group is especially exposed throughout the Grand Canyon in northwest Arizona, as well as local regions of southwest Utah, such as the Virgin River valley region. It occurs in Arizona at Chino Point, Sycamore Canyon, and famously at Sedona as parts of Oak Creek Canyon. In the Sedona region, it is overlain by the Hermit Formation, and the colorful Schnebly Hill Formation.
The Shinarump Conglomerate is a geologic formation found in the Four Corners region of the United States. It was deposited in the early part of the Late Triassic period.
The geology of Ohio formed beginning more than one billion years ago in the Proterozoic eon of the Precambrian. The igneous and metamorphic crystalline basement rock is poorly understood except through deep boreholes and does not outcrop at the surface. The basement rock is divided between the Grenville Province and Superior Province. When the Grenville Province crust collided with Proto-North America, it launched the Grenville orogeny, a major mountain building event. The Grenville mountains eroded, filling in rift basins and Ohio was flooded and periodically exposed as dry land throughout the Paleozoic. In addition to marine carbonates such as limestone and dolomite, large deposits of shale and sandstone formed as subsequent mountain building events such as the Taconic orogeny and Acadian orogeny led to additional sediment deposition. Ohio transitioned to dryland conditions in the Pennsylvanian, forming large coal swamps and the region has been dryland ever since. Until the Pleistocene glaciations erased these features, the landscape was cut with deep stream valleys, which scoured away hundreds of meters of rock leaving little trace of geologic history in the Mesozoic and Cenozoic.
The geology of Utah, in the western United States, includes rocks formed at the edge of the proto-North American continent during the Precambrian. A shallow marine sedimentary environment covered the region for much of the Paleozoic and Mesozoic, followed by dryland conditions, volcanism, and the formation of the basin and range terrain in the Cenozoic.
The (Upper) Late Pennsylvanian Manakacha Formation is a cliff-forming, sandstone, red-orange geologic unit, formed from an addition of eolian sand, added to marine transgression deposits,, and found throughout sections of the Grand Canyon. It is one of the lower members of the Supai Group, with the Supai Group found in other sections of Arizona, especially in the Verde Valley region, or as a basement unit below the Mogollon Rim, just eastwards or part of the basement Supai Group of the southwest & south Colorado Plateau.