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Graneros Shale
The Graneros Shale is a geologic formation in the United States identified in the Great Plains as well as New Mexico that dates to the Cenomanian Age of the Cretaceous Period. It is defined as the finely sandy argillaceous or clayey ''near-shore/marginal-marine'' shale that lies above the older, ''non-marine'' Dakota sand and mud, but below the younger, chalky ''open-marine'' shale of the Greenhorn. This definition was made in Colorado by G. K. Gilbert and has been adopted in other states that use Gilbert's division of the Benton's shales into Carlile, Greenhorn, and Graneros. These states include Kansas, Texas, Oklahoma, Nebraska, and New Mexico as well as corners of Minnesota and Iowa. North Dakota, South Dakota, Wyoming, and Montana have somewhat different usages — in particular, north and west of the Black Hills, the same rock and fossil layer is named Belle Fourche Shale. Naming and Rank F.B. Meek and F.V. Hayden originated the scientific names for the series of C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
El Vado Lake . The former town of El Vado, which in 1910 had a population of 1,000, is now beneath the waters of El Vado Lake.
The eastern shore of the lake is the El Vado Lake State Park, featuring over 100 camping and picnic sites, and two improved boat ramps. The lake is a destination for salmon and trout fishing, as well as for boating. Unlike nearby < ...
El Vado Lake is a reservoir located in Rio Arriba County, in northern New Mexico in the southwestern United States. Water is impounded by the earth-filled El Vado Dam, on the Rio Chama, long and high, completed in 1935. The lake is long and over wide, and lies at an elevation of . The area was formerly part of the Tierra Amarilla Land Grant The Tierra Amarilla Land Grant in northern New Mexico and southern Colorado consists of (929 sq miles) of mountainous land. The government of New Mexico awarded it to Manuel Martinez and his offspring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado
Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas to the east, and Oklahoma to the southeast. Colorado is noted for its landscape of mountains, forests, High Plains (United States), high plains, mesas, canyons, plateaus, rivers, and desert lands. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains. Colorado is the List of U.S. states and territories by area, eighth-largest U.S. state by area and the List of U.S. states and territories by population, 21st by population. The United States Census Bureau estimated the population of Colorado to be 5,957,493 as of July 1, 2024, a 3.2% increase from the 2020 United States census. The region has been inhabited by Native Americans in the United St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oklahoma
Oklahoma ( ; Choctaw language, Choctaw: , ) is a landlocked U.S. state, state in the South Central United States, South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northeast, Arkansas to the east, New Mexico to the west, and Colorado to the northwest. Partially in the western extreme of the Upland South, it is the List of U.S. states and territories by area, 20th-most extensive and the List of U.S. states and territories by population, 28th-most populous of the 50 United States. Its residents are known as Oklahomans and its capital and largest city is Oklahoma City. The state's name is derived from the Choctaw language, Choctaw words , 'people' and , which translates as 'red'. Oklahoma is also known informally by its List of U.S. state and territory nicknames, nickname, "The Sooner State", in reference to the Sooners, American pioneer, American settlers who staked their claims in formerly American Indian-o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Texas
Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the west, and has Mexico-United States border, an international border with the Mexican states of Chihuahua (state), Chihuahua, Coahuila, Nuevo León, and Tamaulipas to the south and southwest. Texas has Texas Gulf Coast, a coastline on the Gulf of Mexico to the southeast. Covering and with over 31 million residents as of 2024, it is the second-largest state List of U.S. states and territories by area, by area and List of U.S. states and territories by population, population. Texas is nicknamed the ''Lone Star State'' for its former status as the independent Republic of Texas. Spain was the first European country to Spanish Texas, claim and control Texas. Following French colonization of Texas, a short-lived colony controlled by France, Mexico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carlile Shale
The Carlile Shale is a Turonian age Upper Cretaceous, Upper/Late Cretaceous series shale geologic Formation (geology), formation in the central-western United States, including in the Great Plains region of Colorado, Kansas, Nebraska, New Mexico, North Dakota, South Dakota, and Wyoming. History of investigation The Carlile Shale was first named by Grove Karl Gilbert for exposures at Carlile Spring, located about west of Pueblo, Colorado. He described it as a medium gray shale, capped with limestone or sandstone, and assigned it to the Benton Group. By 1931, William Walden Rubey and his coinvestigators had mapped it into Kansas and the Black Hills. Rubey also first assigned it to the Colorado Group. C.H. Dane assigned it to the Mancos Shale in New Mexico in 1948. Description The formation is composed of marine deposits of the generally retreating phase (hemi-cycle) of the Greenhorn cycle of the Western Interior Seaway, which followed the advancing phase of the same cycle that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenhorn Limestone
The Greenhorn Limestone or Greenhorn Formation is a geologic formation in the Great Plains Region of the United States, dating to the Cenomanian and Turonian ages of the Late Cretaceous period. The formation gives its name to the Greenhorn cycle of the Western Interior Seaway. Description The formation was named for the Greenhorn Station on Greenhorn Creek in Colorado in 1896 by Grove Karl Gilbert; and it is the namesake of the Greenhorn Marine Cycle of the Cretaceous Western Interior Seaway. With the underlying Graneros Shale and Dakota Formation, it records the progressive stage of Greenhorn Marine Cycle while the overlying Carlile Shale records the regressive stage. The Greenhorn unit name is recognized in the Great Plains Region from Minnesota and Iowa to New Mexico to Montana and the Dakotas. In much of Alberta and Saskatchewan, the "Second White-Specked Shale" contains limy equivalents of the Greenhorn. In Kansas, the Greenhorn Formation is divided into the (lowest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argillite
Argillite () is a fine-grained sedimentary rock composed predominantly of Friability, indurated clay particles. Argillaceous rocks are basically lithified muds and Pelagic sediment, oozes. They contain variable amounts of silt-sized particles. The argillites grade into shale when the Fissility (geology), fissile layering typical of shale is developed. Another name for poorly lithified argillites is ''mudstone''. These rocks, although variable in composition, are typically high in aluminium and silica with variable alkali and alkaline earth cations. The term pelite, ''pelitic'' or ''pelite'' is often applied to these sediments and rocks. Metamorphism of argillites produces slate, phyllite, and pelitic schist. Belt Supergroup The Belt Supergroup, an assemblage of rocks of late Precambrian (Mesoproterozoic) age, includes thick sequences of argillite, as well as other metamorphosed or semi-metamorphosed mudstones.Schieber, J. 1990. Significance of styles of epicontinental shale sedi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenomanian
The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretaceous series (stratigraphy), Series. An age is a unit of geochronology; it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding age. Both age and stage bear the same name. As a unit of geologic time measure, the Cenomanian Age spans the time between 100.5 and 93.9 million years ago (Mya). In the geologic timescale, it is preceded by the Albian and is followed by the Turonian. The Upper Cenomanian starts around at 95 Mya. The Cenomanian is coeval with the Woodbinian of the regional timescale of the Gulf of Mexico and the early part of the Eaglefordian of the regional timescale of the East Coast of the United States. At the end of the Cenomanian, an anoxic event took place, called the Cenomani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Plains
The Great Plains is a broad expanse of plain, flatland in North America. The region stretches east of the Rocky Mountains, much of it covered in prairie, steppe, and grassland. They are the western part of the Interior Plains, which include the mixed grass prairie, the tallgrass prairie between the Great Lakes and Appalachian Plateau, and the Taiga Plains Ecozone, Taiga Plains and Boreal Plains Ecozone, Boreal Plains ecozones in Northern Canada. "Great Plains", or Western Plains, is also the ecoregion of the Great Plains or the western portion of the Great Plains, some of which in the farthest west is known as the High Plains. The Great Plains lie across both the Central United States and Western Canada, encompassing: *Most or all of the U.S. states of Kansas, Nebraska, and North Dakota, North and South Dakota; *Eastern parts of the U.S. states of Colorado, Montana, and Wyoming; *Parts of the U.S. states of New Mexico, Oklahoma, Texas; *Sometimes western parts of Iowa, Minnesot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (geology)
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by Abraham Gottlob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dakota Formation
The Dakota is a sedimentary rock, sedimentary geologic unit name of Formation (stratigraphy), formation and Group (stratigraphy), group rank in Midwestern North America. The Dakota units are generally composed of sandstones, mudstones, clays, and shales deposited in the Mid-Cretaceous opening of the Western Interior Seaway.Monroe, James S. and Wicander, Reed (1997) ''The Changing Earth: Exploring Geology and Evolution'' (2nd edition) Wadsworth Publishing Company, Belmont, California, page 610, The usage of the name Dakota for this particular Albian-Cenomanian strata is exceptionally widespread; from British Columbia and Alberta to Montana and Wisconsin to Colorado and Kansas to Utah and Arizona. It is famous for producing massive colorful rock formations in the Rocky Mountains and the Great Plains of the United States, and for preserving both Fossil track, dinosaur footprints and early deciduous tree leaves. Owing to extensive weathering of older rocks during the Jurassic and Tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenhorn Formation
The Greenhorn Limestone or Greenhorn Formation is a geologic formation in the Great Plains Region of the United States, dating to the Cenomanian and Turonian ages of the Late Cretaceous period. The formation gives its name to the Greenhorn cycle of the Western Interior Seaway. Description The formation was named for the Greenhorn Station on Greenhorn Creek in Colorado in 1896 by Grove Karl Gilbert; and it is the namesake of the Greenhorn Marine Cycle of the Cretaceous Western Interior Seaway. With the underlying Graneros Shale and Dakota Formation, it records the progressive stage of Greenhorn Marine Cycle while the overlying Carlile Shale records the regressive stage. The Greenhorn unit name is recognized in the Great Plains Region from Minnesota and Iowa to New Mexico to Montana and the Dakotas. In much of Alberta and Saskatchewan, the "Second White-Specked Shale" contains limy equivalents of the Greenhorn. In Kansas, the Greenhorn Formation is divided into the (lowest) L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
