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53-484: The range is typical of the Basin and Range Province with isolated high mountains surrounded by downfaulted basins filled with sediments. The rocks of the range include Paleozoic sedimentary and metamorphic rocks intruded by Mesozoic igneous rocks and covered by Mesozoic and Cenozoic volcanic rocks . The highest peak in the range is Quinn Peak , reaching 9,085 ft (2,769 m). Other mountain peaks include: Today

106-510: A configuration which has given rise to increased shearing along the continental margin . The tectonic activity responsible for the extension in the Basin and Range is a complex and controversial issue among the geoscience community. The most accepted hypothesis suggests that crustal shearing associated with the San Andreas Fault caused spontaneous extensional faulting similar to that seen in

159-415: A given ecoregion are more similar to each other than to those of surrounding ecoregions and together form a conservation unit. Freshwater systems include rivers , streams , lakes , and wetlands . Freshwater ecoregions are distinct from terrestrial ecoregions, which identify biotic communities of the land, and marine ecoregions, which are biotic communities of the oceans. A map of Freshwater Ecoregions of

212-578: A group of related geologic features formed by crustal extension during the Cenozoic era (66.0 million years ago to present). The study of metamorphic core complexes has provided valuable insight into the extensional processes driving Basin and Range formation. Prior to the Eocene Epoch (55.8 ±0.2 to 33.9 ±0.1 Ma) the convergence rate of the Farallon and North American plates was fast, the angle of subduction

265-469: A holistic, "weight-of-evidence" approach where the importance of various factors may vary. An example of the algorithmic approach is Robert Bailey 's work for the U.S. Forest Service, which uses a hierarchical classification that first divides land areas into very large regions based on climatic factors, and subdivides these regions, based first on dominant potential vegetation, and then by geomorphology and soil characteristics. The weight-of-evidence approach

318-509: A set of ecoregions identified by WWF whose conservation would achieve the goal of saving a broad diversity of the Earth's ecosystems, includes a number of areas highlighted for their freshwater biodiversity values. The Global 200 preceded Freshwater Ecoregions of the World and incorporated information from regional freshwater ecoregional assessments that had been completed at that time. Sources related to

371-407: A web application developed by Resolve and Google Earth Engine. An ecoregion is a "recurring pattern of ecosystems associated with characteristic combinations of soil and landform that characterise that region". Omernik (2004) elaborates on this by defining ecoregions as: "areas within which there is spatial coincidence in characteristics of geographical phenomena associated with differences in

424-547: Is an ecologically and geographically defined area that is smaller than a bioregion , which in turn is smaller than a biogeographic realm . Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural communities and species . The biodiversity of flora , fauna and ecosystems that characterise an ecoregion tends to be distinct from that of other ecoregions. In theory, biodiversity or conservation ecoregions are relatively large areas of land or water where

477-426: Is analogous to that used for terrestrial ecoregions. Major habitat types are identified: polar, temperate shelves and seas, temperate upwelling, tropical upwelling, tropical coral, pelagic (trades and westerlies), abyssal, and hadal (ocean trench). These correspond to the terrestrial biomes . The Global 200 classification of marine ecoregions is not developed to the same level of detail and comprehensiveness as that of

530-596: Is exemplified by James Omernik's work for the United States Environmental Protection Agency , subsequently adopted (with modification) for North America by the Commission for Environmental Cooperation . The intended purpose of ecoregion delineation may affect the method used. For example, the WWF ecoregions were developed to aid in biodiversity conservation planning, and place a greater emphasis than

583-417: Is mostly arid and sparsely populated, although there are several major metropolitan areas, such as Reno , Las Vegas , Salt Lake City , Phoenix , Tucson , El Paso — Ciudad Juárez , Mexicali , and Hermosillo . It is generally accepted that basin and range topography is the result of extension and thinning of the lithosphere , which is composed of crust and upper mantle . Extensional environments like

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636-526: Is optimal for all taxa. Ecoregions reflect the best compromise for as many taxa as possible. Secondly, ecoregion boundaries rarely form abrupt edges; rather, ecotones and mosaic habitats bound them. Thirdly, most ecoregions contain habitats that differ from their assigned biome . Biogeographic provinces may originate due to various barriers, including physical (plate tectonics, topographic highs), climatic (latitudinal variation, seasonal range) and ocean chemical related (salinity, oxygen levels). The history of

689-473: Is therefore thought to be unrelated to the kind of extension produced by mantle upwelling which may cause narrow rift zones, such as those of the Afar triple junction . Geologic processes that elevate heat flow are varied, however some researchers suggest that heat generated at a subduction zone is transferred to the overriding plate as subduction proceeds. Fluids along fault zones then transfer heat vertically through

742-599: The Himalayas and the Sahara . The boundaries of ecoregions are often not as decisive or well recognized, and are subject to greater disagreement. Ecoregions are classified by biome type, which are the major global plant communities determined by rainfall and climate. Forests, grasslands (including savanna and shrubland), and deserts (including xeric shrublands ) are distinguished by climate ( tropical and subtropical vs. temperate and boreal climates) and, for forests, by whether

795-832: The Wasatch Fault , the Colorado Plateau and the Rio Grande Rift . The province extends north to the Columbia Plateau and south as far as the Trans-Mexican Volcanic Belt in Mexico , though the southern boundaries of the Basin and Range are debated. In Mexico, the Basin and Range Province is dominated by and largely synonymous with the Mexican Plateau . Evidence suggests that the less-recognized southern portion of

848-450: The "ecoregion" as a unit of analysis. The " Global 200 " is the list of ecoregions identified by WWF as priorities for conservation . Terrestrial ecoregions are land ecoregions, as distinct from freshwater and marine ecoregions. In this context, terrestrial is used to mean "of land" (soil and rock), rather than the more general sense "of Earth " (which includes land and oceans). WWF (World Wildlife Fund) ecologists currently divide

901-427: The Basin and Range are characterized by listric normal faulting , or faults that level out with depth. Opposing normal faults link at depth producing a horst and graben geometry, where horst refers to the upthrown fault block and graben to the down dropped fault block. The average crustal thickness of the Basin and Range Province is approximately 30–35 km and is comparable to extended continental crust around

954-542: The Basin and Range province are controversial, and several competing hypotheses attempt to explain them. Key events preceding Basin and Range extension in the western United States include a long period of compression due to the subduction of the Farallon plate under the west coast of the North American continental plate which stimulated the thickening of the crust. Most of the pertinent tectonic plate movement associated with

1007-561: The Early Miocene with the southern portion of the province representing a greater degree of displacement than the north. Evidence exists to suggest that extension initially began in the southern Basin and Range and propagated north over time. Clarence Dutton famously compared the many narrow parallel mountain ranges that distinguish the unique topography of the Basin and Range to an "army of caterpillars crawling northward." The tectonic mechanisms responsible for lithospheric extension in

1060-558: The Earth. The use of the term ecoregion is an outgrowth of a surge of interest in ecosystems and their functioning. In particular, there is awareness of issues relating to spatial scale in the study and management of landscapes . It is widely recognized that interlinked ecosystems combine to form a whole that is "greater than the sum of its parts". There are many attempts to respond to ecosystems in an integrated way to achieve "multi-functional" landscapes, and various interest groups from agricultural researchers to conservationists are using

1113-481: The Great Basin. However, plate movement alone does not account for the high elevation of the Basin and Range region. The western United States is a region of high heat flow which lowers the density of the lithosphere and stimulates isostatic uplift as a consequence. Lithospheric regions characterized by elevated heat flow are weak and extensional deformation can occur over a broad region. Basin and Range extension

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1166-587: The Jungo Road west for 35 miles to Bottle Creek Road. The Jackson Mountain Range can also be reached by taking the Leonard Creek or Bottle Creek Roads south from State Route 140 . The two wildernesses are divided by Trout Creek Road. The South Jackson area has canyons on the west side of the mountains which provide access for dayhiking and backpacking. McGill, Bliss, and Alaska Canyons are scenic. The eastern slopes of

1219-581: The North Jackson Mountains Wilderness. Due to the ruggedness of the area; base camping and dayhiking is recommended. Basin and Range Province The Basin and Range Province is a vast physiographic region covering much of the inland Western United States and northwestern Mexico . It is defined by unique basin and range topography , characterized by abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins. The physiography of

1272-547: The Omernik or Bailey systems on floral and faunal differences between regions. The WWF classification defines an ecoregion as: A large area of land or water that contains a geographically distinct assemblage of natural communities that: According to WWF, the boundaries of an ecoregion approximate the original extent of the natural communities prior to any major recent disruptions or changes. WWF has identified 867 terrestrial ecoregions, and approximately 450 freshwater ecoregions across

1325-593: The Pacific-Farallon Ridge was subducted beneath North America ending subduction along this part of the Pacific margin; however, the Farallon plate continued to subduct into the mantle . The movement at this boundary divided the Pacific-Farallon Ridge and spawned the San Andreas transform fault , generating an oblique strike-slip component. Today, the Pacific plate moves north-westward relative to North America,

1378-525: The South Jackson are gentler in terrain and more suitable for horse travel. Photography, wildlife and wild horse viewing opportunities exists throughout the wilderness area. Hunting for mule deer, California bighorn sheep, antelope and game birds is popular in the area. The North Jackson area provides for camping, dayhiking, photography, wildlife and wild horse viewing opportunities. Deer Creek, Mary Sloan, Happy Creek, and Jackson Creek are scenic streams in

1431-560: The WWF concept prioritizes biogeography, that is, the distribution of distinct species assemblages. In 2017, an updated terrestrial ecoregions dataset was released in the paper "An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm" led by E. Dinerstein with 48 co-authors. Using recent advances in satellite imagery the ecoregion perimeters were refined and the total number reduced to 846 (and later 844), which can be explored on

1484-519: The World (TEOW), led by D. Olsen, E. Dinerstein, E. Wikramanayake, and N. Burgess. While the two approaches are related, the Bailey ecoregions (nested in four levels) give more importance to ecological criteria and climate zones, while the WWF ecoregions give more importance to biogeography, that is, the distribution of distinct species assemblages. The TEOW framework originally delineated 867 terrestrial ecoregions nested into 14 major biomes, contained with

1537-783: The World, released in 2008, has 426 ecoregions covering virtually the entire non-marine surface of the earth. World Wildlife Fund (WWF) identifies twelve major habitat types of freshwater ecoregions: Large lakes, large river deltas, polar freshwaters, montane freshwaters, temperate coastal rivers, temperate floodplain rivers and wetlands, temperate upland rivers, tropical and subtropical coastal rivers, tropical and subtropical floodplain rivers and wetlands, tropical and subtropical upland rivers, xeric freshwaters and endorheic basins, and oceanic islands. The freshwater major habitat types reflect groupings of ecoregions with similar biological, chemical, and physical characteristics and are roughly equivalent to biomes for terrestrial systems. The Global 200 ,

1590-480: The authors was to support global biodiversity conservation by providing a "fourfold increase in resolution over that of the 198 biotic provinces of Dasmann (1974) and the 193 units of Udvardy (1975)." In 2007, a comparable set of Marine Ecoregions of the World (MEOW) was published, led by M. Spalding, and in 2008 a set of Freshwater Ecoregions of the World (FEOW) was published, led by R. Abell. Bailey's ecoregion concept prioritizes ecological criteria and climate, while

1643-677: The broad latitudinal divisions of polar, temperate, and tropical seas, with subdivisions based on ocean basins (except for the southern hemisphere temperate oceans, which are based on continents). Major marine biogeographic realms, analogous to the eight terrestrial biogeographic realms , represent large regions of the ocean basins: Arctic , Temperate Northern Atlantic , Temperate Northern Pacific , Tropical Atlantic , Western Indo-Pacific , Central Indo-Pacific , Eastern Indo-Pacific , Tropical Eastern Pacific , Temperate South America , Temperate Southern Africa , Temperate Australasia , and Southern Ocean . A similar system of identifying areas of

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1696-416: The crust. This model has led to increasing interest in geothermal systems in the Basin and Range, and requires consideration of the continued influence of the fully subducted Farallon plate in the extension responsible for the Basin and Range Province. In some localities in the Basin and Range, metamorphic basement is visible at the surface. Some of these are metamorphic core complexes (MCC), an idea that

1749-401: The delineation of ecoregions an imperfect science. Another complication is that environmental conditions across an ecoregion boundary may change very gradually, e.g. the prairie-forest transition in the midwestern United States, making it difficult to identify an exact dividing boundary. Such transition zones are called ecotones . Ecoregions can be categorized using an algorithmic approach or

1802-405: The early 1970s, the term 'ecoregion' was introduced (short for ecological region), and R.G. Bailey published the first comprehensive map of U.S. ecoregions in 1976. The term was used widely in scholarly literature in the 1980s and 1990s, and in 2001 scientists at the U.S. conservation organization World Wildlife Fund (WWF) codified and published the first global-scale map of Terrestrial Ecoregions of

1855-616: The greater Basin and Range physiographic region. Nor should it be confused with the Basin and Range National Monument , located in Southern Nevada, which is one small part of the much larger province. The Basin and Range Province includes much of western North America . In the United States, it is bordered on the west by the eastern fault scarp of the Sierra Nevada and spans over 500 miles (800 km) to its eastern border marked by

1908-501: The land surface of the Earth into eight biogeographical realms containing 867 smaller terrestrial ecoregions (see list ). The WWF effort is a synthesis of many previous efforts to define and classify ecoregions. The eight realms follow the major floral and faunal boundaries, identified by botanists and zoologists, that separate the world's major plant and animal communities. Realm boundaries generally follow continental boundaries, or major barriers to plant and animal distribution, like

1961-648: The majority of the range is divided into two federally protected wilderness area, the North Jackson Mountains Wilderness and the South Jackson Mountains Wilderness . The South Jackson Wilderness offers a panoramic view including the Black Rock Desert , from the top of King Lear Peak at 8,442 feet. Topography of the wilderness is characterized by steep-sided and sharp-crested ridges spotted with juniper and are considered to be

2014-874: The most rugged of the Bureau of Land Management 's Winnemucca District. Remnants of the historic Red Butte copper mining district can still be found nearby. The North Jackson Mountains Wilderness' topography is characterized by steep-sided, sharp-crested ridges spotted with juniper, and V-shaped rocky valleys. Elevations in the Wilderness range from 4,000 feet to the high point of Parrot Peak at 8,400 feet. Deep rugged canyons are laden with aspen, willow, and cottonwood groves. Several riparian streams support small populations of introduced rainbow trout. The Jackson Mountains are located in Humboldt County , 56 miles west of Winnemucca, Nevada . Access can be reached from Winnemucca by taking

2067-463: The oceans for conservation purposes is the system of large marine ecosystems (LMEs), developed by the US National Oceanic and Atmospheric Administration (NOAA). A freshwater ecoregion is a large area encompassing one or more freshwater systems that contains a distinct assemblage of natural freshwater communities and species. The freshwater species, dynamics, and environmental conditions within

2120-430: The probability of encountering different species and communities at any given point remains relatively constant, within an acceptable range of variation (largely undefined at this point). Ecoregions are also known as "ecozones" ("ecological zones"), although that term may also refer to biogeographic realms . Three caveats are appropriate for all bio-geographic mapping approaches. Firstly, no single bio-geographic framework

2173-702: The province is White Mountain Peak in California , while the lowest point is the Badwater Basin in Death Valley at −282 feet (−86 m). The province's climate is arid, with numerous ecoregions . Most North American deserts are located within it. The Basin and Range Province should not be confused with the Great Basin , a region defined by its unique hydrological characteristics (internal drainage) that overlaps much of

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2226-701: The province is bounded on the east by the Laramide Thrust Front of the Sierra Madre Oriental and on the west by the Gulf of California and Baja Peninsula with notably less faulting apparent in the Sierra Madre Occidental in the center of the southernmost Basin and Range Province. Common geographic features include numerous endorheic basins , ephemeral lakes, plateaus, and bolson valleys alternating with mountains (as described below). The area

2279-710: The province is the result of tectonic extension that began around 17 million years ago in the early Miocene epoch. The numerous ranges within the province in the United States are collectively referred to as the "Great Basin Ranges", although many are not actually in the Great Basin . Major ranges include the Snake Range , the Panamint Range , the White Mountains , and the Sandia Mountains . The highest point fully within

2332-578: The province occurred in the Neogene period (23.03-2.58 million years ago) and continues to the present. By the Early Miocene sub-epoch (23.03-15.97 million years ago), much of the Farallon plate had been consumed, and the seafloor spreading ridge that separated the Farallon plate from the Pacific plate ( Pacific-Farallon Ridge ) approached North America. In the Middle Miocene (15.97-11.63 million years ago),

2385-415: The quality, health, and integrity of ecosystems ". "Characteristics of geographical phenomena" may include geology , physiography , vegetation, climate, hydrology , terrestrial and aquatic fauna , and soils, and may or may not include the impacts of human activity (e.g. land use patterns, vegetation changes). There is significant, but not absolute, spatial correlation among these characteristics, making

2438-408: The term is somewhat vague. It has been used in many contexts: forest classifications (Loucks, 1962), biome classifications (Bailey, 1976, 2014), biogeographic classifications ( WWF / Global 200 scheme of Olson & Dinerstein, 1998), etc. The phrase "ecological region" was widely used throughout the 20th century by biologists and zoologists to define specific geographic areas in research. In

2491-454: The terrestrial ecoregions; only the priority conservation areas are listed. See Global 200 Marine ecoregions for a full list of marine ecoregions. In 2007, TNC and WWF refined and expanded this scheme to provide a system of comprehensive near shore (to 200 meters depth) Marine Ecoregions of the World (MEOW). The 232 individual marine ecoregions are grouped into 62 marine provinces , which in turn group into 12 marine realms , which represent

2544-913: The trees are predominantly conifers ( gymnosperms ), or whether they are predominantly broadleaf ( Angiosperms ) and mixed (broadleaf and conifer). Biome types like Mediterranean forests, woodlands, and scrub ; tundra ; and mangroves host very distinct ecological communities, and are recognized as distinct biome types as well. Marine ecoregions are: "Areas of relatively homogeneous species composition , clearly distinct from adjacent systems….In ecological terms, these are strongly cohesive units, sufficiently large to encompass ecological or life history processes for most sedentary species." They have been defined by The Nature Conservancy (TNC) and World Wildlife Fund (WWF) to aid in conservation activities for marine ecosystems . Forty-three priority marine ecoregions were delineated as part of WWF's Global 200 efforts. The scheme used to designate and classify marine ecoregions

2597-486: The world's 8 major biogeographical realms. Subsequent regional papers by the co-authors covering Africa, Indo-Pacific, and Latin America differentiate between ecoregions and bioregions, referring to the latter as "geographic clusters of ecoregions that may span several habitat types, but have strong biogeographic affinities, particularly at taxonomic levels higher than the species level (genus, family)". The specific goal of

2650-424: The world. The crust in conjunction with the upper mantle comprises the lithosphere . The base of the lithosphere beneath the Basin and Range is estimated to be about 60–70 km. Opinions vary regarding the total extension of the region; however, the median estimate is about 100% total lateral extension. Total lateral displacement in the Basin and Range varies from 60 to 300 km since the onset of extension in

2703-410: Was completely consumed and volcanic activity ceased, in part. Olivine basalt from the oceanic ridge erupted around 17 Ma and extension began. In addition to small amounts of Nevada petroleum , the Basin and Range Province supplies nearly all the copper and most of the gold , silver , and barite mined in the United States. Ecoregions An ecoregion ( ecological region )

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2756-451: Was first developed based on studies in this province. A metamorphic core complex occurs when lower crust is brought to the surface as a result of extension. MCCs in the Basin and Range were not interpreted as being related to crustal extension until after the 1960s. Since then, similar deformational patterns have been identified in MCCs in the Basin and Range and has led geologists to examine them as

2809-557: Was shallow, and the slab width was huge. During the Eocene the Farallon plate subduction -associated compressive forces of the Laramide , Sevier and Nevada orogenies ended, plate interactions changed from orthogonal compression to oblique strike-slip , and volcanism in the Basin and Range Province flared up ( Mid-Tertiary ignimbrite flare-up ). It is suggested that this plate continued to be underthrust until about 19 Ma, at which time it

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