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Cañadón Asfalto Basin
The Cañadón Asfalto Basin ( es, Cuenca de Cañadón Asfalto) is an irregularly shaped sedimentary basin located in north-central Patagonia, Argentina. The basin stretches from and partly covers the North Patagonian Massif in the north, a high forming the boundary of the basin with the Neuquén Basin in the northwest, to the Cotricó High in the south, separating the basin from the Golfo San Jorge Basin. It is located in the southern part of Río Negro Province and northern part of Chubut Province. The eastern boundary of the basin is the North Patagonian Massif separating it from the offshore Valdés Basin and it is bound in the west by the Patagonian Andes, separating it from the small Ñirihuau Basin. The basin started forming in the Early Jurassic, with the break-up of Pangea and the creation of the South Atlantic, when extensional tectonics, including rifting, formed several basins in eastern South America and southwestern Africa. The accommodation space in the Cañadón Asf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patagonia
Patagonia () refers to a geographical region that encompasses the southern end of South America, governed by Argentina and Chile. The region comprises the southern section of the Andes Mountains with lakes, fjords, temperate rainforests, and glaciers in the west and deserts, tablelands and steppes to the east. Patagonia is bounded by the Pacific Ocean on the west, the Atlantic Ocean to the east, and many bodies of water that connect them, such as the Strait of Magellan, the Beagle Channel, and the Drake Passage to the south. The Colorado and Barrancas rivers, which run from the Andes to the Atlantic, are commonly considered the northern limit of Argentine Patagonia. The archipelago of Tierra del Fuego is sometimes included as part of Patagonia. Most geographers and historians locate the northern limit of Chilean Patagonia at Huincul Fault, in Araucanía Region.Manuel Enrique Schilling; Richard WalterCarlson; AndrésTassara; Rommulo Vieira Conceição; Gustavo Walter Bertotto; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary
The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ago to the present. The Quaternary Period is divided into two epochs: the Pleistocene (2.58 million years ago to 11.7 thousand years ago) and the Holocene (11.7 thousand years ago to today, although a third epoch, the Anthropocene, has been proposed but is not yet officially recognised by the ICS). The Quaternary Period is typically defined by the cyclic growth and decay of continental ice sheets related to the Milankovitch cycles and the associated climate and environmental changes that they caused. Research history In 1759 Giovanni Arduino proposed that the geological strata of northern Italy could be divided into four successive formations or "orders" ( it, quattro ordini). The term "quaternary" was introduced by Jules Desnoye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unconformity
An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval of time before deposition of the younger layer, but the term is used to describe any break in the sedimentary geologic record. The significance of angular unconformity (see below) was shown by James Hutton, who found examples of Hutton's Unconformity at Jedburgh in 1787 and at Siccar Point in 1788. The rocks above an unconformity are younger than the rocks beneath (unless the sequence has been overturned). An unconformity represents time during which no sediments were preserved in a region or were subsequently eroded before the next deposition. The local record for that time interval is missing and geologists must use other clues to discover that part of the geologic history of that area. The interval of geologic time not represented is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacustrine
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger oceans, they do form part of the Earth's water cycle. Lakes are distinct from lagoons, which are generally coastal parts of the ocean. Lakes are typically larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which usually flow in a channel on land. Most lakes are fed and drained by rivers and streams. Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvial
In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluvioglacial is used. Fluvial processes Fluvial processes include the motion of sediment and erosion or deposition on the river bed. The movement of water across the stream bed exerts a shear stress directly onto the bed. If the cohesive strength of the substrate is lower than the shear exerted, or the bed is composed of loose sediment which can be mobilized by such stresses, then the bed will be lowered purely by clearwater flow. In addition, if the river carries significant quantities of sediment, this material can act as tools to enhance wear of the bed ( abrasion). At the same time the fragments themselves are ground down, becoming smaller and more rounded (attrition). Sediment in rivers is transported as either bedload (the coarser fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accommodation (geology)
Accommodation is a fundamental concept in sequence stratigraphy, a subdiscipline of geology. It is defined as the space that is available for the deposition of sediments. Accommodation space can be pictured as the volume between the actual surface and the theoretical equilibrium surface where deposition and erosion are in balance at every point. In marine environments, this equilibrium level is sea level. In marine environments, changes in accommodation on long temporal scales is mainly determined by tectonics or by changes in eustatic sea level. In fluvial environments, changes in accommodation are controlled by the gradient, discharge and sediment supply. In the lower parts of river systems, the change of accommodation in the fluvial system is controlled by the changes in marine accommodation. The term is also sometimes used to described processes by which room is made for plutons to intrude country rock Country rock is a genre of music which fuses rock and country. It w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rift
In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben with normal faulting and rift-flank uplifts mainly on one side. Where rifts remain above sea level they form a rift valley, which may be filled by water forming a rift lake. The axis of the rift area may contain volcanic rocks, and active volcanism is a part of many, but not all, active rift systems. Major rifts occur along the central axis of most mid-ocean ridges, where new oceanic crust and lithosphere is created along a divergent boundary between two tectonic plates. ''Failed rifts'' are the result of continental rifting that failed to continue to the point of break-up. Typically the transition from rifting to spreading develops at a triple junction where three converging rifts meet over a hotspot. Two of these evolve to the poi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensional Tectonics
Extensional tectonics is concerned with the structures formed by, and the tectonic processes associated with, the stretching of a planetary body's crust or lithosphere. Deformation styles The types of structure and the geometries formed depend on the amount of stretching involved. Stretching is generally measured using the parameter ''β'', known as the ''beta factor'', where : \beta = \frac \,, ''t''0 is the initial crustal thickness and ''t''1 is the final crustal thickness. It is also the equivalent of the strain parameter ''stretch''. Low beta factor In areas of relatively low crustal stretching, the dominant structures are high to moderate angle normal faults, with associated half grabens and tilted fault blocks. High beta factor In areas of high crustal stretching, individual extensional faults may become rotated to too low a dip to remain active and a new set of faults may be generated. Large displacements may juxtapose syntectonic sediments against metamorphic roc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe and Asia from the "New World" of the Americas in the European perception of the World. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and North and South America to the west. As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). The Atlantic Ocean is divided in two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean split at about 8°N. Scientific explorations of the A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valdés Basin
Valdez or Valdés may refer to: People *Valdez (surname) *Valdés (surname) *Valdez (Brazilian footballer) (born 1943), Brazilian footballer * Valdez “Val” Demings, U.S. politician Geography *Valdés, Asturias, Spain *Valdez, Alaska, United States **Valdez oil terminal *Valdez, California, United States *Valdez, Esmeraldas, Ecuador *Valdez, Florida, United States *Valdes Island, Canada *Valdés Peninsula, Argentina Other uses * Valdez (acrobatic), a back walkover that begins in a sitting position *''Exxon Valdez ''Oriental Nicety'', formerly ''Exxon Valdez'', ''Exxon Mediterranean'', ''SeaRiver Mediterranean'', ''S/R Mediterranean'', ''Mediterranean'', and ''Dong Fang Ocean'', was an oil tanker that gained notoriety after running aground in Prince Wi ...'', oil tanker involved in an oil spill in Alaska in 1989 ** Valdez Blockade, a protest by Alaskan fishermen in 1993 {{disambig, geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golfo San Jorge Basin
The Golfo San Jorge Basin ( es, Cuenca del Golfo San Jorge) is a hydrocarbon-rich sedimentary basin located in eastern Patagonia, Argentina. The basin covers the entire San Jorge Gulf and an inland area west of it, having one half located in Santa Cruz Province, Argentina, Santa Cruz Province and the other in Chubut Province. The northern boundary of the basin is the North Patagonian Massif while the Deseado Massif forms the southern boundary of the basin. The basin has largely developed under condition of extensional tectonics, including rifting. The basin is of paleontological significance as it hosts six out of 22 defining formations for the South American land mammal age, SALMA classification, the geochronology for the Cenozoic used in South America. At the center of the basin accumulated sediments reach more than of thickness. Oil was first discovered in 1907 and over the years it has become the second most productive hydrocarbon basin in Argentina after Neuquén Basin. St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuquén Basin
Neuquén Basin ( es, Cuenca Neuquina) is a sedimentary basin covering most of Neuquén Province in Argentina. The basin originated in the Jurassic and developed through alternating continental and marine conditions well into the Tertiary. The basin bounds to the west with the Andean Volcanic Belt, to the southeast with the North Patagonian Massif and to the northeast with the San Rafael Block and to the east with the Sierra Pintada System. The basin covers an area of approximately .Howell et al., 2005 One age of the SALMA classification, the Colloncuran, is defined in the basin, based on the Collón Curá Formation, named after the Collón Curá River, a tributary of the Limay River. Description Jurassic and Cretaceous marine transgressions from the Pacific are recorded in the sediments of Neuquén Basin. These marine sediments belong to Cuyo Group, Tordillo Formation, Auquilco Formation and Vaca Muerta. In the Late Cretaceous, conditions in the neighboring Andean orogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
