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High Desert (Oregon)
The Oregon High Desert is located in the southeast of the U.S. state of Oregon, east of the Cascade Range and south of the Blue Mountains (Pacific Northwest), Blue Mountains. The desert covers most of five Oregon counties and averages in altitude. The northern region is part of the Columbia River drainage basin, Columbia Plateau, where higher levels of rainfall allow the largest industry on private land to be the cultivation of alfalfa and hay. The southwest region is part of the Great Basin and the southeast is the lower Owyhee River watershed. The U.S. Bureau of Land Management owns most of the region's public land and manages more than including five rivers designated as National Wild and Scenic Rivers System, Wild and Scenic. Compared to Western Oregon, the high desert is arid, averaging of annual rainfall. Contrary to its name, most of the high desert is not dry enough to truly qualify as desert, and biologically, most of the region is classified as shrubland or steppe. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frenchglen, Oregon
Frenchglen is an unincorporated community in Harney County, Oregon, United States. It is south of Burns on Oregon Route 205. Frenchglen is near Steens Mountain and Malheur National Wildlife Refuge, and is home to the historic Frenchglen Hotel, an Oregon State Heritage Site built in 1917. In addition to the hotel, which includes a restaurant, the town has a K-8 school divided into two classes, a general store with gas pumps, and a county roads department base. History The community is named after the French-Glenn Livestock Company, founded by Hugh J. Glenn and later joined by his son-in-law, Peter French. French-Glenn built its headquarters there in 1872. The post office took the name Frenchglen after it was moved there. Education The zoned K-8 school is Frenchglen Elementary School (of Frenchglen School District 16). The school began operations in 1927. An individual named Walt Riddle bought all of the school building bonds to make the existence of a school a certainty. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Wild And Scenic Rivers System
The National Wild and Scenic Rivers System was created by the Wild and Scenic Rivers Act of 1968 (Public Law 90-542), enacted by the U.S. Congress to preserve certain rivers with outstanding natural, cultural, and recreational values in a free-flowing condition for the enjoyment of present and future generations. The Act is notable for safeguarding the special character of these rivers, while also recognizing the potential for their appropriate use and development. It encourages river management that crosses political boundaries and promotes public participation in developing goals for river protection. The Act, signed into law by President Lyndon B. Johnson in the height of the United States environmental era, states:"It is hereby declared to be the policy of the United States that certain selected rivers of the Nation which, with their immediate environments, possess outstandingly remarkable scenic, recreational, geologic, fish and wildlife, historic, cultural or other similar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mule Deer
The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer. Unlike the related white-tailed deer (''Odocoileus virginianus''), which is found throughout most of North America east of the Rocky Mountains and in the valleys of the Rocky Mountains from Idaho and Wyoming northward, mule deer are found only on the western Great Plains, in the Rocky Mountains, in the southwest United States, and on the west coast of North America. Mule deer have also been introduced to Argentina and Kauai, Kauai, Hawaii. Taxonomy Mule deer can be divided into two main groups: the mule deer (''sensu stricto'') and the black-tailed deer. The first group includes all subspecies, except ''O. h. columbianus'' and ''Sitka deer, O. h. sitkensis'', which are in the black-tailed deer group. The two main groups have been treated as separate species, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coyote
The coyote (''Canis latrans''), also known as the American jackal, prairie wolf, or brush wolf, is a species of canis, canine native to North America. It is smaller than its close relative, the Wolf, gray wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecological niche as the golden jackal does in Eurasia; however, the coyote is generally larger. The coyote is listed as Least Concern, least concern by the International Union for Conservation of Nature, due to its wide distribution and abundance throughout North America. The species is versatile, able to adapt to and expand into environments modified by humans; urban coyotes are common in many cities. The coyote was sighted in eastern Panama (across the Panama Canal from their home range) for the first time in 2013. The coyote has 19 recognized subspecies. The average male weighs and the average female . Their fur color is predominantly light gray and red or fulvous int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pronghorn
The pronghorn (, ) (''Antilocapra americana'') is a species of artiodactyl (even-toed, hoofed) mammal indigenous to interior western and central North America. Though not an antelope, it is known colloquially in North America as the American antelope, prong buck, pronghorn antelope, and prairie antelope, because it closely resembles the antelopes of the Old World and fills a similar ecological niche due to parallel evolution. It is the only surviving member of the family Antilocapridae. During the Pleistocene epoch, about 11 other antilocaprid species existed in North America, many with long or spectacularly twisted horns.Smithsonian Institution. North American MammalsPronghorn ''Antilocapra americana'' Three other genera ('' Capromeryx'', '' Stockoceros'' and '' Tetrameryx'') existed when humans entered North America but are now extinct. The pronghorn's closest living relatives are the giraffe and okapi. See Fig. S10 in Supplementary Information. The antilocaprids are part of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Age
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages, and greenhouse periods during which there are no glaciers on the planet. Earth is currently in the ice age called Quaternary glaciation. Individual pulses of cold climate within an ice age are termed '' glacial periods'' (''glacials, glaciations, glacial stages, stadials, stades'', or colloquially, ''ice ages''), and intermittent warm periods within an ice age are called '' interglacials'' or ''interstadials''. In glaciology, the term ''ice age'' is defined by the presence of extensive ice sheets in the northern and southern hemispheres. By this definition, the current Holocene epoch is an interglacial period of an ice age. The accumulation of anthropogenic greenhouse gases is projected to delay the next glacial period. History of research ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene followed the Oligocene and preceded the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by distinct global events but by regionally defined transitions from the warmer Oligocene to the cooler Pliocene Epoch. During the Early Miocene, Afro-Arabia collided with Eurasia, severing the connection between the Mediterranean and Indian Oceans, and allowing the interchange of fauna between Eurasia and Africa, including the dispersal of proboscideans and Ape, hominoids into Eurasia. During the late Miocene, the conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plate Tectonics
Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by Earth science, geoscientists after seafloor spreading was validated in the mid-to-late 1960s. The processes that result in plates and shape Earth's crust are called ''tectonics''. Tectonic plates also occur in other planets and moons. Earth's lithosphere, the rigid outer shell of the planet including the crust (geology), crust and upper mantle, is fractured into seven or eight major plates (depending on how they are defined) and many minor plates or "platelets". Where the plates meet, their relative motion determines the type of plate boundary (or fault (geology), fault): , , or . The relative movement of the plates typically ranges from zero to 10 cm annu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basin And Range Topography
Basin and range topography is characterized by alternating parallel mountain ranges and valleys. It is a result of crustal extension due to mantle upwelling, gravitational collapse, crustal thickening, or relaxation of confining stresses. The extension results in the thinning and deformation of the upper crust, causing it to fracture and create a series of long parallel normal faults. This results in block faulting, where the blocks of rock between the normal faults either subside, uplift, or tilt. The movement of these blocks results in the alternating valleys and mountains. As the crust thins, it also allows heat from the mantle to more easily melt rock and form magma, resulting in increased volcanic activity. Types of faulting Symmetrical faulting: horst and graben With crustal extension, a series of normal faults which occur in groups, form in close proximity and dipping in opposite directions. As the crust extends it fractures in series of fault planes, some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault-block Mountain
Fault blocks are very large blocks of rock, sometimes hundreds of kilometres in extent, created by Tectonics, tectonic and localized stresses in Crust (geology), Earth's crust. Large areas of bedrock are broken up into blocks by Fault (geology), faults. Blocks are characterized by relatively uniform lithology. The largest of these fault blocks are called crustal blocks. Large crustal blocks broken off from tectonic plates are called terranes. Those terranes which are the full thickness of the lithosphere are called microplates. Continent-sized blocks are called variously ''microcontinents, continental ribbons, H-blocks, extensional allochthons and outer highs.'' Because most stresses relate to the tectonic activity of moving Plate tectonics, plates, most motion between blocks is horizontal, that is parallel to the Earth's crust by Fault (geology)#Strike-slip faults, strike-slip faults. However vertical movement of blocks produces much more dramatic results. Landforms (mounta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steens Mountain
Steens Mountain is a large fault-block mountain in the northwest United States, located in Harney County, Oregon. Stretching some north to south, on its east side it rises from the Alvord Desert at an elevation of about to at the summit. Steens Mountain is not part of a mountain range but is properly a single mountain, the largest of Oregon's fault-block mountains.Conkling, C., Jackman, E. R., & Scharff, J. (1967)Steens Mountain in Oregon's high desert country Caxton Press. Retrieved April 25, 2022 The Steens Mountain Wilderness encompasses of Steens Mountain. of the Wilderness are protected from grazing and free of cattle. Geology Steens Mountain is the remnant of a long shield volcano. The east face of Steens Mountain is composed mainly of basalts stacked one upon another. Lava flows several hundreds of feet thick inundated the region between 17 and 14 million years ago. Chemical data from magma deposits from the area reveal three distinct stages of volcanism. Layers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steppe
In physical geography, a steppe () is an ecoregion characterized by grassland plains without closed forests except near rivers and lakes. Steppe biomes may include: * the montane grasslands and shrublands biome * the tropical and subtropical grasslands, savannas, and shrublands biome * the temperate grasslands, savannas, and shrublands biome A steppe is usually covered with grass and shrubs, depending on the season and latitude. The term ''steppe climate'' denotes a semi-arid climate, which is encountered in regions too dry to support a forest, but not dry enough to be a desert. Steppes are usually characterized by a semi-arid or continental climate. Temperature extremes can be recorded in the summer of up to and in winter of down to . Besides this major seasonal difference, fluctuations between day and night are also significant: in both the highlands of Mongolia and northern Nevada, can be reached during the day with sub-freezing readings at night. Steppes ave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
