HOME
*



picture info

Hopi Buttes
Hopi Buttes volcanic field is a monogenetic volcanic field located on the Colorado Plateau mostly on the Navajo Reservation around the town of Dilkon in northeastern Arizona north of Holbrook. The volcanic field covers an area of approximately and contains about 300 maars and diatremes. The erosional exposure of the deposits varies with those in the eastern portion exhibiting the shallowly eroded maar deposits and those in the western portion the more deeply eroded feeder diatremes. The maars result from explosive interaction of the hot diatreme material with the groundwater system and result in a mixture of volcanic tuff material and sediments of the Miocene–Pliocene lacustrine sediments of the Bidahochi Formation. In the western portion of the field the buttes consist of the feeder diatremes of monchiquite and nepheline syenite magmas. Most of the volcanic activity occurred between 8.5 and 6 million years ago, with the most recent dated at 4.2 million years ago.
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Hopi Buttes
Hopi Buttes volcanic field is a monogenetic volcanic field located on the Colorado Plateau mostly on the Navajo Reservation around the town of Dilkon in northeastern Arizona north of Holbrook. The volcanic field covers an area of approximately and contains about 300 maars and diatremes. The erosional exposure of the deposits varies with those in the eastern portion exhibiting the shallowly eroded maar deposits and those in the western portion the more deeply eroded feeder diatremes. The maars result from explosive interaction of the hot diatreme material with the groundwater system and result in a mixture of volcanic tuff material and sediments of the Miocene–Pliocene lacustrine sediments of the Bidahochi Formation. In the western portion of the field the buttes consist of the feeder diatremes of monchiquite and nepheline syenite magmas. Most of the volcanic activity occurred between 8.5 and 6 million years ago, with the most recent dated at 4.2 million years ago.
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Bidahochi Formation
The Pliocene to Late Neogene Bidahochi Formation lies at an elevation of about to at the southeast of the Colorado Plateau; the deposits are from Hopi Lake (also called Bidahochi Lake), and the deposits extend southwards to the region at the north perimeter of the White Mountains of central-east Arizona. Bidahochi Lake is thought to have been a single "large lake, or several shallow, and ephemeral ones." Various fossil types are found; also bird trackways. The Bidahochi Formation contains basalt flows that form an erosional protecting unit above the highly erodable Chinle Formation. The Bidahochi Formation extends approximately 112 miles north–south, or north-northwest by south-southeast, a length approximately equivalent to today's Great Salt Lake of Utah. The Bidahochi is possibly the only extensive nonvolcanic Neogene formation of the Colorado Plateau. It has been studied by geologists for clues to conditions on the plateau during this time interval and to test hypothe ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Geography Of The Navajo Nation
Geography (from Greek: , ''geographia''. Combination of Greek words ‘Geo’ (The Earth) and ‘Graphien’ (to describe), literally "earth description") is a field of science devoted to the study of the lands, features, inhabitants, and phenomena of Earth. The first recorded use of the word γεωγραφία was as a title of a book by Greek scholar Eratosthenes (276–194 BC). Geography is an all-encompassing discipline that seeks an understanding of Earth and its human and natural complexities—not merely where objects are, but also how they have changed and come to be. While geography is specific to Earth, many concepts can be applied more broadly to other celestial bodies in the field of planetary science. One such concept, the first law of geography, proposed by Waldo Tobler, is "everything is related to everything else, but near things are more related than distant things." Geography has been called "the world discipline" and "the bridge between the human and t ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Monogenetic Volcanic Fields
Monogenetic may refer to: * Monogenetic in biology, of or pertaining to monogenesis (Mendelian inheritance) * Monogenetic volcanic field in geology, a cluster of volcanoes that only erupted once * Monogenetic theory of pidgins in linguistics, a theory about the origin of creole languages See also * Monogenous (other) * Monogenic (other) Monogenic may refer to: * Monogenic signal, in the theory of analytic signals * Monogenic disorder, disease, inheritance, or trait, a single gene disorder resulting from a single mutated gene ** Monogenic diabetes, or maturity-onset diabetes of ...
{{disambiguation ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Landforms Of Apache County, Arizona
A landform is a natural or anthropogenic land feature on the solid surface of the Earth or other planetary body. Landforms together make up a given terrain, and their arrangement in the landscape is known as topography. Landforms include hills, mountains, canyons, and valleys, as well as shoreline features such as bays, peninsulas, and seas, including submerged features such as mid-ocean ridges, volcanoes, and the great ocean basins. Physical characteristics Landforms are categorized by characteristic physical attributes such as elevation, slope, orientation, stratification, rock exposure and soil type. Gross physical features or landforms include intuitive elements such as berms, mounds, hills, ridges, cliffs, valleys, rivers, peninsulas, volcanoes, and numerous other structural and size-scaled (e.g. ponds vs. lakes, hills vs. mountains) elements including various kinds of inland and oceanic waterbodies and sub-surface features. Mountains, hills, plateaux, and plains are the fo ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Volcanic Fields Of Arizona
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and most are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot volcanism, of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plates slide pa ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

List Of Volcanoes In The United States Of America
A list of volcanoes in the United States and its territories. Alaska American Samoa Arizona California Colorado Hawaii /[./[Https://www.sci.news/geology/puhahonu-shield-volcano-08435.html Puhahonu - - - Unknown Idaho Illinois Louisiana Michigan Mississippi Missouri Nevada New Hampshire New Jersey New Mexico Sierra Grande -. -. -. 2.41 to 2.88 million years ago Northern Mariana Islands Oregon Texas Utah Virginia Washington Wyoming See also *Geothermal energy in the United States *List of Cascade volcanoes *List of large volume volcanic eruptions in the Basin and Range Province *List of volcanoes in Canada *List of volcanoes in Mexico *List of volcanoes in Russia *List of volcanic craters in Alaska *List of volcanic craters in Arizo ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Cambridge University Press
Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press A university press is an academic publishing house specializing in monographs and scholarly journals. Most are nonprofit organizations and an integral component of a large research university. They publish work that has been reviewed by schola ... in the world. It is also the King's Printer. Cambridge University Press is a department of the University of Cambridge and is both an academic and educational publisher. It became part of Cambridge University Press & Assessment, following a merger with Cambridge Assessment in 2021. With a global sales presence, publishing hubs, and offices in more than 40 Country, countries, it publishes over 50,000 titles by authors from over 100 countries. Its publishing includes more than 380 academic journals, monographs, reference works, school and uni ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Morale Claim Maar
Morale, also known as esprit de corps (), is the capacity of a group's members to maintain belief in an institution or goal, particularly in the face of opposition or hardship. Morale is often referenced by authority figures as a generic value judgment of the willpower, obedience, and self-discipline of a group tasked with performing duties assigned by a superior. According to Alexander H. Leighton, "morale is the capacity of a group of people to pull together persistently and consistently in pursuit of a common purpose". Morale is important in the military, because it improves unit cohesion. With good morale, a force will be less likely to give up or surrender. Morale is usually assessed at a collective, rather than an individual level. In wartime, civilian morale is also important. Esprit de corps is considered to be an important part of a fighting unit. Definition Military history experts have not agreed on a precise definition of "morale". Clausewitz's comments on the s ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Geographic Coordinates
The geographic coordinate system (GCS) is a spherical or ellipsoidal coordinate system for measuring and communicating positions directly on the Earth as latitude and longitude. It is the simplest, oldest and most widely used of the various spatial reference systems that are in use, and forms the basis for most others. Although latitude and longitude form a coordinate tuple like a cartesian coordinate system, the geographic coordinate system is not cartesian because the measurements are angles and are not on a planar surface. A full GCS specification, such as those listed in the EPSG and ISO 19111 standards, also includes a choice of geodetic datum (including an Earth ellipsoid), as different datums will yield different latitude and longitude values for the same location. History The invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene, who composed his now-lost ''Geography'' at the Library of Alexandria in the 3rd century  ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Magma
Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natural satellites. Besides molten rock, magma may also contain suspended crystals and gas bubbles. Magma is produced by melting of the mantle or the crust in various tectonic settings, which on Earth include subduction zones, continental rift zones, mid-ocean ridges and hotspots. Mantle and crustal melts migrate upwards through the crust where they are thought to be stored in magma chambers or trans-crustal crystal-rich mush zones. During magma's storage in the crust, its composition may be modified by fractional crystallization, contamination with crustal melts, magma mixing, and degassing. Following its ascent through the crust, magma may feed a volcano and be extruded as lava, or it may solidify underground to form an intrusion, such as a ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Nepheline Syenite
Nepheline syenite is a holocrystalline plutonic rock that consists largely of nepheline and alkali feldspar. The rocks are mostly pale colored, grey or pink, and in general appearance they are not unlike granites, but dark green varieties are also known. Phonolite is the fine-grained extrusive equivalent. Petrology Nepheline syenites are silica-undersaturated and some are peralkaline (terms discussed in igneous rock). Nepheline is a feldspathoid, a solid-solution mineral, that does not coexist with quartz; rather, nepheline would react with quartz to produce alkali feldspar. They are distinguished from ordinary basic syenites not only by the presence of nepheline but also by the occurrence of many other minerals rich in alkalis and in rare earths and other incompatible elements. Alkali feldspar dominates, commonly represented by orthoclase and the exsolved lamellar albite, form perthite. In some rocks the potash feldspar, in others the soda feldspar predominates. Fresh clear m ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]