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Navajo Section
The Navajo Section is a physiographic section of the larger Colorado Plateaus Province, which in turn is part of the larger Intermontane Plateaus physiographic Division. Geography The Navajo Section is located in northeastern Arizona and northwestern New Mexico. It is named for the Navajo Nation, with about half of the area of the section on the Navajo Reservation. The section is characterized by broad rolling plains on easily eroded and carved rocks, with cuestas (ridges) and tablelands capped by gently dipping resistant sandstone beds. One of the most prominent landform features of the Navajo Section is Shiprock, a monadnock formation near the town of Shiprock, New Mexico. Elevations The lowest point in the Navajo Section is about , near the Four Corners area. The boundary between this section and the Canyon Lands Section is nearby, in the San Juan River basin. The highest point of the Navajo Section is at Chromo Mountain on the Continental Divide near Chama, New Mexic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navajo Section
The Navajo Section is a physiographic section of the larger Colorado Plateaus Province, which in turn is part of the larger Intermontane Plateaus physiographic Division. Geography The Navajo Section is located in northeastern Arizona and northwestern New Mexico. It is named for the Navajo Nation, with about half of the area of the section on the Navajo Reservation. The section is characterized by broad rolling plains on easily eroded and carved rocks, with cuestas (ridges) and tablelands capped by gently dipping resistant sandstone beds. One of the most prominent landform features of the Navajo Section is Shiprock, a monadnock formation near the town of Shiprock, New Mexico. Elevations The lowest point in the Navajo Section is about , near the Four Corners area. The boundary between this section and the Canyon Lands Section is nearby, in the San Juan River basin. The highest point of the Navajo Section is at Chromo Mountain on the Continental Divide near Chama, New Mexic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chama, New Mexico
Chama is a village in Rio Arriba County, New Mexico, United States. The population was 1,022 at the 2010 census. The village is located in the Rocky Mountains about south of the Colorado-New Mexico border. Geography Chama is located at (36.894777, -106.584406), on the Rio Chama, south of the Colorado border. According to the United States Census Bureau, the village has a total area of , all of it land. History Chama is the western terminus of the Cumbres and Toltec Scenic Railroad, a steam-driven, narrow gauge heritage railway which carries visitors to and from Osier, Colorado, and Antonito, Colorado, during the summer months. It is the remaining 64 mile portion of the Denver & Rio Grande Railroad's San Juan Extension built in the 1880s between Alamosa, Colorado, and Durango, Colorado. The route was abandoned in the late 1960s and the tracks from Chama westward to Durango were torn up soon afterwards. File:C&TS Chama Depot 2012-10-24.JPG, The Chama train depot File:DRGW 483 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fruitland Formation
The Fruitland Formation is a geologic formation found in the San Juan Basin in the states of New Mexico and Colorado, in the United States of America. It contains fossils dating it to the Campanian age of the late Cretaceous.Fruitland Formation at .org The Fruitland Formation shares its name with . That city is on what was the western shore of the |
San Juan Basin
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 N-S and E-W. The San Juan Basin is an asymmetric structural depression in the Colorado Plateau province, with varying elevation and nearly in topographic relief. Its most striking features include Chaco Canyon (northwestern New Mexico, between Farmington and Santa Fe) and Chacra Mesa. The basin lies west of the Continental Divide, and its main drainage is the southwest- to west-flowing San Juan River, which eventually joins the Colorado River in Utah. Climate of the basin is arid to semiarid, with an annual precipitation of and an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocline
A monocline (or, rarely, a monoform) is a step-like fold in rock strata consisting of a zone of steeper dip within an otherwise horizontal or gently-dipping sequence. Formation Monoclines may be formed in several different ways (see diagram) * By differential compaction over an underlying structure, particularly a large fault at the edge of a basin due to the greater compactibility of the basin fill, the amplitude of the fold will die out gradually upwards. * By mild reactivation of an earlier extensional fault during a phase of inversion causing folding in the overlying sequence. * As a form of fault propagation fold during upward propagation of an extensional fault in basement into an overlying cover sequence. * As a form of fault propagation fold during upward propagation of a reverse fault in basement into an overlying cover sequence. Examples * Waterpocket Fold in Capitol Reef National Park, Utah *Comb Ridge in southern Utah * Grandview-Phantom Monocline in Grand Can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Badlands
Badlands are a type of dry terrain where softer sedimentary rocks and clay-rich soils have been extensively eroded."Badlands" in ''Chambers's Encyclopædia''. London: George Newnes, 1961, Vol. 2, p. 47. They are characterized by steep slopes, minimal vegetation, lack of a substantial regolith, and high drainage density.A.J. Parsons and A.D. Abrahams, Editors (2009) ''Geomorphology of Desert Environments'' (2nd ed.) Springer Science & Business Media Ravines, gullies, buttes, hoodoos and other such geologic forms are common in badlands. Badlands are found on every continent except Antarctica, being most common where there are unconsolidated sediments. They are often difficult to navigate by foot, and are unsuitable for agriculture. Most are a result of natural processes, but destruction of vegetation by overgrazing or pollution can produce anthropogenic badlands. Badlands topography Badlands are characterized by a distinctive badlands topography. This is terrain in which w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesas
A mesa is an isolated, flat-topped elevation, ridge or hill, which is bounded from all sides by steep escarpments and stands distinctly above a surrounding plain. Mesas characteristically consist of flat-lying soft sedimentary rocks capped by a more resistant layer or layers of harder rock, e.g. shales overlain by sandstones. The resistant layer acts as a caprock that forms the flat summit of a mesa. The caprock can consist of either sedimentary rocks such as sandstone and limestone; dissected lava flows; or a deeply eroded duricrust. Unlike ''plateau'', whose usage does not imply horizontal layers of bedrock, e.g. Tibetan Plateau, the term ''mesa'' applies exclusively to the landforms built of flat-lying strata. Instead, flat-topped plateaus are specifically known as '' tablelands''.Duszyński, F., Migoń, P. and Strzelecki, M.C., 2019. ''Escarpment retreat in sedimentary tablelands and cuesta landscapes–Landforms, mechanisms and patterns.'' ''Earth-Science Reviews, no. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buttes
__NOTOC__ In geomorphology, a butte () is an isolated hill with steep, often vertical sides and a small, relatively flat top; buttes are smaller landforms than mesas, plateaus, and tablelands. The word ''butte'' comes from a French word meaning knoll (but of any size); its use is prevalent in the Western United States, including the southwest where ''mesa'' (Spanish for "table") is used for the larger landform. Due to their distinctive shapes, buttes are frequently landmarks in plains and mountainous areas. To differentiate the two landforms, geographers use the rule of thumb that a mesa has a top that is wider than its height, while a butte has a top that is narrower than its height. Formation Buttes form by weathering and erosion when hard caprock overlies a layer of less resistant rock that is eventually worn away. The harder rock on top of the butte resists erosion. The caprock provides protection for the less resistant rock below from wind abrasion which leaves it stan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenozoic
The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configuration of continents. It is the latest of three geological eras since complex life evolved, preceded by the Mesozoic and Paleozoic. It started with the Cretaceous–Paleogene extinction event, when many species, including the non-avian dinosaurs, became extinct in an event attributed by most experts to the impact of a large asteroid or other celestial body, the Chicxulub impactor. The Cenozoic is also known as the Age of Mammals because the terrestrial animals that dominated both hemispheres were mammalsthe eutherians (placentals) in the northern hemisphere and the metatherians (marsupials, now mainly restricted to Australia) in the southern hemisphere. The extinction of many groups allowed mammals and birds to greatly diversify so that l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.Blatt, Harvey and Robert J. Tracy (1996) ''Petrology: Igneous, Sedimentary and Metamorphic'', 2nd ed., Freeman, pp. 281–292 Shale is characterized by its tendency to split into thin layers ( laminae) less than one centimeter in thickness. This property is called '' fissility''. Shale is the most common sedimentary rock. The term ''shale'' is sometimes applied more broadly, as essentially a synonym for mudrock, rather than in the more narrow sense of clay-rich fissile mudrock. Texture Shale typically exhibits varying degrees of fissility. Because of the parallel orientation of clay mineral flakes in shale, it breaks into thin layers, often splintery and usually parallel to the otherwise indistinguishable beddin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grand Canyon
The Grand Canyon (, yuf-x-yav, Wi:kaʼi:la, , Southern Paiute language: Paxa’uipi, ) is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is long, up to wide and attains a depth of over a mile (). The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, Grand Canyon–Parashant National Monument, the Hualapai Indian Reservation, the Havasupai Indian Reservation and the Navajo Nation. President Theodore Roosevelt was a major proponent of the preservation of the Grand Canyon area and visited it on numerous occasions to hunt and enjoy the scenery. Nearly two billion years of Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
