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Pah Rah Range
The Pah Rah Range is a mountain range located in western Nevada in Washoe County just to the northeast of Reno. It is a hook shaped range with the main eastern portion oriented northwest–southeast, approximately long. The northwest flowing Cottonwood Creek in Warm Springs Valley is bounded on three sides by the range. To the south and east the Truckee River forms the boundary and Pyramid Lake is at the northeast. Spanish Springs Valley north of Reno forms the southwest margin. To the north the narrow Mullen Pass separates the Pah Rah Range from the Virginia Mountains. The highest peaks (in order from south to north) are Pond Peak (elevation ), Virginia Peak (elevation ) and Pah Rah Peak (elevation ). In the southwest portion Spanish Springs Peak (elevation ) is the highest. Both Pond Peak and Virginia Peak host several radio towers. Virginia Peak is also the site of a doppler radar station. Interstate 80 follows the Truckee River basin to the south of the range. Nevada ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washoe County, Nevada
Washoe County () is a county in the U.S. state of Nevada. As of the 2020 census, the population was 486,492, making it Nevada's second-most populous county. Its county seat is Reno. Washoe County is included in the Reno, NV Metropolitan Statistical Area. History Washoe County was created on November 25, 1861, as one of the original nine counties of the Nevada Territory. It is named after the Washoe people who originally inhabited the area. It was consolidated with Roop County in 1864. Washoe City was the first county seat in 1861 and was replaced by Reno in 1871. In 1911, a small band of Shoshone and Bannock led by Mike Daggett killed four stockmen in Washoe County. A posse was formed, and on February 26, 1911, at the Battle of Kelley Creek, eight of Daggett's band were killed, along with one member of the posse, Ed Hogle. Three children and a woman who survived the battle were captured. The remains of some of the members of the band were repatriated from the Smithsonian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surveyor (surveying)
Surveying or land surveying is the technique, profession, art, and science of determining the terrestrial two-dimensional or three-dimensional positions of points and the distances and angles between them. A land surveying professional is called a land surveyor. These points are usually on the surface of the Earth, and they are often used to establish maps and boundaries for ownership, locations, such as the designed positions of structural components for construction or the surface location of subsurface features, or other purposes required by government or civil law, such as property sales. Surveyors work with elements of geodesy, geometry, trigonometry, regression analysis, physics, engineering, metrology, programming languages, and the law. They use equipment, such as total stations, robotic total stations, theodolites, GNSS receivers, retroreflectors, 3D scanners, LiDAR sensors, radios, inclinometer, handheld tablets, optical and digital levels, subsurface locato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bighorn Sheep
The bighorn sheep (''Ovis canadensis'') is a species of sheep native to North America. It is named for its large horns. A pair of horns might weigh up to ; the sheep typically weigh up to . Recent genetic testing indicates three distinct subspecies of ''Ovis canadensis'', one of which is endangered: ''O. c. sierrae''. Sheep originally crossed to North America over the Bering Land Bridge from Siberia; the population in North America peaked in the millions, and the bighorn sheep entered into the mythology of Native Americans. By 1900, the population had crashed to several thousand, due to diseases introduced through European livestock and overhunting. Taxonomy and genetics ''Ovis canadensis'' is one of two species of mountain sheep in North America; the other species being ''O. dalli'', the Dall sheep. Wild sheep crossed the Bering land bridge from Siberia into Alaska during the Pleistocene (about 750,000 years ago) and subsequently spread through western North America as far s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pronghorn Antelope
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.Smithsonian Institution. North American MammalsPronghorn ''Antilocapra americana''/ref> Three other genera (''Capromeryx'', ''Stockoceros'' and ''Tetrameryx'') existed when humans entered North America but are now extinct. As a member of the superfamily Giraffoidea, the pronghorn's closest living relatives are the giraffe and okapi. See Fig. S10 in Supplementary Information. The Giraffoidea are in turn membe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desert Magazine
''Desert Magazine'' was a monthly regional publication based in the Colorado Desert published between 1937 and 1985. A print version bearing the same name has been revived in the Coachella Valley town of Palm Desert near Palm Springs, California. History Editors ''Desert Magazine'' was founded, edited and published from 1937 to 1958 by Randall Henderson (1888–1970). New editors followed until the magazine closed print publication in 1985. It was revived as an on-line magazine in 2006.Desert Magazine: History Retrieved July 7, 2010 Publication The magazine focused on the desert country of the Southwestern United States ...[...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 is preceded by the Oligocene and is followed by 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 a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch. During the Early Miocene, the Arabian Peninsula collided with Eurasia, severing the connection between the Mediterranean and Indian Ocean, and allowing a faunal interchange to occur between Eurasia and Africa, including the dispersal of proboscideans into Eurasia. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andesite
Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende. Andesite is the extrusive equivalent of plutonic diorite. Characteristic of subduction zones, andesite represents the dominant rock type in island arcs. The average composition of the continental crust is andesitic. Along with basalts, andesites are a component of the Martian crust. The name ''andesite'' is derived from the Andes mountain range, where this rock type is found in abundance. It was first applied by Christian Leopold von Buch in 1826. Description Andesite is an aphanitic (fine-grained) igneous rock that is intermediate in its content of silica and low in alkali metals. It has less than 20% quartz and 10% feldspathoid by volume, with at least 65% of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of Venus, which cover ~80% of the surface, are basaltic; the lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flows that can spread over great areas before cooling and solidifying. Flood basalts are t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dike (geology)
A dike or dyke, in geological usage, is a sheet of rock that is formed in a fracture of a pre-existing rock body. Dikes can be either magmatic or sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock. Clastic dikes are formed when sediment fills a pre-existing crack.Essentials of Geology, 3rd Ed, Stephen Marshak Magmatic dikes A magmatic dike is a sheet of igneous rock that cuts across older rock beds. It is formed when magma fills a fracture in the older beds and then cools and solidifies. The dike rock is usually more resistant to weathering than the surrounding rock, so that erosion exposes the dike as a natural wall or ridge. It is from these natural walls that dikes get their name. Dikes preserve a record of the fissures through which most mafic magma (fluid magma low in silica) reaches the surface. They are studied by geologists for the clues ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porphyry (geology)
Porphyry ( ) is a textural term for an igneous rock consisting of coarse-grained crystals such as feldspar or quartz dispersed in a fine-grained silicate-rich, generally aphanitic matrix or groundmass. The larger crystals are called phenocrysts. In its non-geologic, traditional use, the term ''porphyry'' refers to the purple-red form of this stone, valued for its appearance. The term ''porphyry'' is from the Ancient Greek (), meaning "purple". Purple was the color of royalty, and the "imperial porphyry" was a deep purple igneous rock with large crystals of plagioclase. Some authors claimed the rock was the hardest known in antiquity. Thus, "imperial"-grade porphyry was prized for monuments and building projects in Imperial Rome and thereafter. Subsequently, the name was given to any igneous rocks with large crystals. The adjective ''porphyritic'' now refers to a certain texture of igneous rock regardless of its chemical and mineralogical composition. Its chief characteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granite
Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers. Granite is typical of a larger family of ''granitic rocks'', or '' granitoids'', that are composed mostly of coarse-grained quartz and feldspars in varying proportions. These rocks are classified by the relative percentages of quartz, alkali feldspar, and plagioclase (the QAPF classification), with true granite representing granitic rocks rich in quartz and alkali feldspar. Most granitic rocks also contain mica or amphibole minerals, though a few (known as leucogranites) contain almost no dark minerals. Granite is near ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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