United States Geological Survey
The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, the natural hazards that threaten it; the organization has four major science disciplines, concerning biology, geography and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility; the USGS is a bureau of the United States Department of the Interior. The USGS employs 8,670 people and is headquartered in Reston, Virginia; the USGS has major offices near Lakewood, Colorado, at the Denver Federal Center, Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world." The agency's previous slogan, adopted on the occasion of its hundredth anniversary, was "Earth Science in the Public Service." Since 2012, the USGS science focus is directed at six topical "Mission Areas", namely Climate and Land Use Change, Core Science Systems, Ecosystems and Minerals and Environmental Health, Natural Hazards, Water.
In December 2012, the USGS split the Energy and Minerals and Environmental Health Mission Area resulting in seven topical Mission Areas, with the two new areas being: Energy and Minerals and Environmental Health. Administratively, it is divided into six Regional Units. Other specific programs include: Earthquake Hazards Program monitors earthquake activity worldwide; the National Earthquake Information Center in Golden, Colorado on the campus of the Colorado School of Mines detects the location and magnitude of global earthquakes. The USGS runs or supports several regional monitoring networks in the United States under the umbrella of the Advanced National Seismic System; the USGS informs authorities, emergency responders, the media, the public, both domestic and worldwide, about significant earthquakes. It maintains long-term archives of earthquake data for scientific and engineering research, it conducts and supports research on long-term seismic hazards. USGS has released the UCERF California earthquake forecast.
As of 2005, the agency is working to create a National Volcano Early Warning System by improving the instrumentation monitoring the 169 volcanoes in U. S. territory and by establishing methods for measuring the relative threats posed at each site. The USGS National Geomagnetism Program monitors the magnetic field at magnetic observatories and distributes magnetometer data in real time; the USGS collaborates with Canadian and Mexican government scientists, along with the Commission for Environmental Cooperation, to produce the North American Environmental Atlas, used to depict and track environmental issues for a continental perspective. The USGS operates the streamgaging network for the United States, with over 7400 streamgages. Real-time streamflow data are available online. National Climate Change and Wildlife Science Center implements partner-driven science to improve understanding of past and present land use change, develops relevant climate and land use forecasts, identifies lands and communities that are most vulnerable to adverse impacts of change from the local to global scale.
Since 1962, the Astrogeology Research Program has been involved in global and planetary exploration and mapping. In collaboration with Stanford University, the USGS operates the USGS-Stanford Ion Microprobe Laboratory, a world-class analytical facility for U--Pb geochronology and trace element analyses of minerals and other earth materials. USGS operates a number of water related programs, notably the National Streamflow Information Program and National Water-Quality Assessment Program. USGS Water data is publicly available from their National Water Information System database; the USGS operates the National Wildlife Health Center, whose mission is "to serve the nation and its natural resources by providing sound science and technical support, to disseminate information to promote science-based decisions affecting wildlife and ecosystem health. The NWHC provides information, technical assistance, research and leadership on national and international wildlife health issues." It is the agency responsible for surveillance of H5N1 avian influenza outbreaks in the United States.
The USGS runs 17 biological research centers in the United States, including the Patuxent Wildlife Research Center. The USGS is investigating collaboration with the social networking site Twitter to allow for more rapid construction of ShakeMaps; the USGS produces several national series of topographic maps which vary in scale and extent, with some wide gaps in coverage, notably the complete absence of 1:50,000 scale topographic maps or their equivalent. The largest and best-known topographic series is the 7.5-minute, 1:24,000 scale, quadrangle, a non-metric scale unique to the United States. Each of these maps covers an area bounded by two lines of latitude and two lines of longitude spaced 7.5 minutes apart. Nearly 57,000 individual maps in this series cover the 48 contiguous states, Hawaii, U. S. territories, areas of Alaska near Anchorage and Prudhoe Bay. The area covered by each map varies with the latitude of its represented location due to convergence of the meridians. At lower latitudes, near 30° north, a 7.5-minute quadrangle contains an area of about 64 square miles.
At 49° north latitude, 49 square miles are contained within a quadrangle of that size. As a unique non-metric map scale, the 1:24,000 scale requires a separate and specialized romer scale for pl
Mission San Gabriel Arcángel
Mission San Gabriel Arcángel is a functioning Roman Catholic mission and a historic landmark in San Gabriel, California. The settlement was founded by Spaniards of the Franciscan order on "The Feast of the Birth of Mary," September 8, 1771, as the fourth of what would become 21 Spanish missions in California. San Gabriel Arcángel, named after the Archangel Gabriel and referred to as the "Godmother of the Pueblo of Los Angeles", was designed by Antonio Cruzado, who hailed from Córdoba, Spain. Cruzado gave the building its strong Moorish architectural influence; the capped buttresses and the tall, narrow windows are unique among the missions of the California chain. Mission San Gabriel was founded on September 8, 1771, by Fray Angel Francisco de Sonera and Fray Pedro Benito Cambon; the planned site for the Mission was along the banks of the Río de Los Temblores. The priests chose an alternate site on a fertile plain located directly alongside the Rio Hondo in the Whittier Narrows; the site of the Misión Vieja is located near the intersection of San Gabriel Boulevard and Lincoln Avenue.
In 1776, a flash flood destroyed much of the crops and ruined the Mission complex, subsequently relocated five miles closer to the mountains in present-day San Gabriel. The Mission is the base. On December 9, 1812, a series of massive earthquakes shook Southern California; the 1812 Wrightwood earthquake caused the three-bell campanario, located adjacent to the chapel's east façade, to collapse. A larger, six-bell structure was subsequently constructed at the far end of the Capilla. While no pictorial record exists to document what the original structure looked like, architectural historian Rexford Newcomb deduced the design and published a depiction in his 1916 work The Franciscan Mission Architecture of Alta California. Legend has it that the founding expedition was confronted by a large group of native Tongva peoples whose intention was to drive the strangers away. One of the priests laid a painting of "Our Lady of Sorrows" on the ground for all to see, whereupon the natives, designated by the settlers as the Gabrieliños made peace with the missionaries, because they were so moved by the painting's beauty.
Today the 300-year-old work hangs in front of and to the left of the old high altar and reredos in the Mission's sanctuary. A large stone cross stands in the center of the Campo Santo, first consecrated in 1778 and again on January 29, 1939, by the Los Angeles Archbishop John Cantwell, it serves as the final resting place for some 6,000 "neophytes. Interred at the Mission are the bodies of numerous Franciscan priests who died during their time of service, as well as the remains of Reverend Raymond Catalan, C. M. F. who undertook the restoration of the Mission's gardens. Entombed at the foot of the altar are the remains of eight Franciscan priests: Miguel Sánchez, Antonio Cruzado, Francisco Dumetz, Roman Ulibarri, Joaquin P. Nunez, Gerónimo Boscana, José Bernardo Sánchez, Blas Ordaz. Buried among the priests is centenarian Eulalia Perez de Guillén Mariné, the "keeper of the keys" under Spanish rule. Well over 25,000 baptisms were conducted at San Gabriel between 1771 and 1834, making it the most prolific in the mission chain.
In its heyday, it furnished food and supplies to settlements and other missions throughout California. A majority of the Mission structures fell into ruins after it was secularized in November 1834; the once-extensive vineyards were falling to decay, with fences broken down and animals roaming through it. The Mission's chapel functioned as a parish church for the City of San Gabriel from 1862 until 1908, when the Claretian Missionaries came to San Gabriel and began the job of rebuilding and restoring the Mission. In 1874, tracks were laid for Southern Pacific Railroad near the mission. In 2012, artifacts from the mission era were found when the tracks were lowered into a trench known as the Alameda Corridor-East. On October 1, 1987 the Whittier Narrows earthquake damaged the property. A significant portion of the original complex has since been restored; the goal of the missions was to become self-sufficient in short order. Farming was the most important industry of any mission. Prior to the missions, the native-Americans had developed a self-sufficient culture.
The missionaries believed the native Tongva people were inferior and in need of conversion to Christianity. The mission priests established what they thought of as a manual training school: to teach the Indians their style of agriculture, the mechanical arts, the raising and care of livestock; the missions, utilizing the labor of the neophytes, produced everything they consumed. After 1811, the mission Indians could be said to sustain the entire military and civil government of California."The names of the rancherias associated with San Gabriel Mission were: Acuragna, Awigna, Cahuenga, Chowigna, Hahaulogna, Houtgna, Isanthcogna, Nacaugna, Pasinogna, Pubugna, Sisitcanogna, Suangna, Toviscanga, Yangna."To efficiently manage its extensive lands, Mission San Gabriel established several outlying sub-missions, known as asistencias. Several of these became or were
A mountain range or hill range is a series of mountains or hills ranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form and alignment that have arisen from the same cause an orogeny. Mountain ranges are formed by a variety of geological processes, but most of the significant ones on Earth are the result of plate tectonics. Mountain ranges are found on many planetary mass objects in the Solar System and are a feature of most terrestrial planets. Mountain ranges are segmented by highlands or mountain passes and valleys. Individual mountains within the same mountain range do not have the same geologic structure or petrology, they may be a mix of different orogenic expressions and terranes, for example thrust sheets, uplifted blocks, fold mountains, volcanic landforms resulting in a variety of rock types. Most geologically young mountain ranges on the Earth's land surface are associated with either the Pacific Ring of Fire or the Alpide Belt.
The Pacific Ring of Fire includes the Andes of South America, extends through the North American Cordillera along the Pacific Coast, the Aleutian Range, on through Kamchatka, Taiwan, the Philippines, Papua New Guinea, to New Zealand. The Andes is 7,000 kilometres long and is considered the world's longest mountain system; the Alpide belt includes Indonesia and Southeast Asia, through the Himalaya, Caucasus Mountains, Balkan Mountains fold mountain range, the Alps, ends in the Spanish mountains and the Atlas Mountains. The belt includes other European and Asian mountain ranges; the Himalayas contain the highest mountains in the world, including Mount Everest, 8,848 metres high and traverses the border between China and Nepal. Mountain ranges outside these two systems include the Arctic Cordillera, the Urals, the Appalachians, the Scandinavian Mountains, the Great Dividing Range, the Altai Mountains and the Hijaz Mountains. If the definition of a mountain range is stretched to include underwater mountains the Ocean Ridges form the longest continuous mountain system on Earth, with a length of 65,000 kilometres.
The mountain systems of the earth are characterized by a tree structure, where mountain ranges can contain sub-ranges. The sub-range relationship is expressed as a parent-child relationship. For example, the White Mountains of New Hampshire and the Blue Ridge Mountains are sub-ranges of the Appalachian Mountains. Equivalently, the Appalachians are the parent of the White Mountains and Blue Ridge Mountains, the White Mountains and the Blue Ridge Mountains are children of the Appalachians; the parent-child expression extends to the sub-ranges themselves: the Sandwich Range and the Presidential Range are children of the White Mountains, while the Presidential Range is parent to the Northern Presidential Range and Southern Presidential Range. The position of mountains influences climate, such as snow; when air masses move up and over mountains, the air cools producing orographic precipitation. As the air descends on the leeward side, it warms again and is drier, having been stripped of much of its moisture.
A rain shadow will affect the leeward side of a range. Mountain ranges are subjected to erosional forces which work to tear them down; the basins adjacent to an eroding mountain range are filled with sediments which are buried and turned into sedimentary rock. Erosion is at work while the mountains are being uplifted until the mountains are reduced to low hills and plains; the early Cenozoic uplift of the Rocky Mountains of Colorado provides an example. As the uplift was occurring some 10,000 feet of Mesozoic sedimentary strata were removed by erosion over the core of the mountain range and spread as sand and clays across the Great Plains to the east; this mass of rock was removed as the range was undergoing uplift. The removal of such a mass from the core of the range most caused further uplift as the region adjusted isostatically in response to the removed weight. Rivers are traditionally believed to be the principal cause of mountain range erosion, by cutting into bedrock and transporting sediment.
Computer simulation has shown that as mountain belts change from tectonically active to inactive, the rate of erosion drops because there are fewer abrasive particles in the water and fewer landslides. Mountains on other planets and natural satellites of the Solar System are isolated and formed by processes such as impacts, though there are examples of mountain ranges somewhat similar to those on Earth. Saturn's moon Titan and Pluto, in particular exhibit large mountain ranges in chains composed of ices rather than rock. Examples include the Mithrim Montes and Doom Mons on Titan, Tenzing Montes and Hillary Montes on Pluto; some terrestrial planets other than Earth exhibit rocky mountain ranges, such as Maxwell Montes on Venus taller than any on Earth and Tartarus Montes on Mars, Jupiter's moon Io has mountain ranges formed from tectonic processes including Boösaule Montes, Dorian Montes, Hi'iaka Montes and Euboea Montes. Peakbagger Ranges Home Page Bivouac.com
The Huntington Library, Art Collections and Botanical Gardens, colloquially known as The Huntington, is a collections-based educational and research institution established by Henry E. Huntington and located in San Marino, United States. In addition to the library, the institution houses an extensive art collection with a focus on 18th- and 19th-century European art and 17th- to mid-20th-century American art; the property includes 120 acres of specialized botanical landscaped gardens, most notably the "Japanese Garden", the "Desert Garden", the "Chinese Garden". As a landowner, Henry Edwards Huntington played a major role in the growth of Southern California. Huntington was born in 1850, in Oneonta, New York, was the nephew and heir of Collis P. Huntington, one of the famous "Big Four" railroad tycoons of 19th century California history. In 1892, Huntington relocated to San Francisco with his first wife, Mary Alice Prentice, as well as their four children, he divorced Mary Alice Prentice in 1906.
He purchased a property of more than 500 acres, known as the "San Marino Ranch" and went on to purchase other large tracts of land in the Pasadena and Los Angeles areas of Los Angeles County for urban and suburban development. As president of the Pacific Electric Railway Company, the regional streetcar and public transit system for the Los Angeles metropolitan area and southern California and of the Los Angeles Railway Company, he spearheaded urban and regional transportation efforts to link together far-flung communities, supporting growth of those communities as well as promoting commerce and tourism, he was one of the founders of the City of San Marino, incorporated in 1913. Huntington's interest in art was influenced in large part by his second wife, Arabella Huntington, with art experts to guide him, he benefited from a post-World War I European market, "ready to sell anything". Before his death in 1927, Huntington amassed "far and away the greatest group of 18th-century British portraits assembled by any one man".
In accordance with Huntington's will, the collection worth $50 million, was opened to the public in 1928. On October 17, 1985, a fire erupted in an elevator shaft of the Huntington Art Gallery and destroyed Sir Joshua Reynolds's 1777 portrait of Mrs. Edwin Lascelles. After a year-long, $1 million refurbishing project, the Huntington Gallery reopened in 1986, with its artworks cleaned of soot and stains. Most of the funds for the cleanup and refurbishing of the Georgian mansion and its artworks came from donations from the Michael J. Connell Foundation and individuals. Both the Federal art-supporting establishment of the National Endowment for the Arts and the National Endowment for the Humanities gave emergency grants, the former of $17,500 to "support conservation and other related costs resulting from a serious fire at the Gallery of Art", the latter of $30,000 to "support the restoration of several fire-damaged works of art that depict the story of Western culture." The library building was designed in 1920, by the southern California architect Myron Hunt in the Mediterranean Revival style.
Hunt's previous commissions for Mr. and Mrs. Huntington included the Huntington's residence in San Marino in 1909, the Huntington Hotel in 1914; the library contains a substantial collection of rare books and manuscripts, concentrated in the fields of British and American history, literature and the history of science. Spanning from the 11th century to the present, the library's holdings contain 7 million items, over 400,000 rare books, over a million photographs and other ephemera. Highlights include one of eleven vellum copies of the Gutenberg Bible known to exist, the Ellesmere manuscript of Chaucer, letters and manuscripts by George Washington, Thomas Jefferson, Benjamin Franklin, Abraham Lincoln, it is the only library in the world with the first two quartos of Hamlet. The Library's Main Exhibition Hall showcases some of the most outstanding rare books and manuscripts in the collection, while the West Hall of the Library hosts rotating exhibitions; the Dibner Hall of the History of Science is a permanent exhibition on the history of science with a focus on astronomy, natural history and light.
With the 2006 acquisition of the Burndy Library, a collection of nearly 60,000 items, the Huntington became one of the top institutions in the world for the study of the history of science and technology. Use of the collection for research is restricted to qualified scholars requiring a doctoral degree or at least candidacy for the PhD, two letters of recommendation from known scholars. Through a rigorous peer-review program, the institution awards 150 grants to scholars in the fields of history, literature and the history of science; the Huntington hosts numerous scholarly events, lectures and workshops. In September 1991, then-director William A. Moffett announced that the library's photographic archive of the Dead Sea Scrolls would
Henry E. Huntington
Henry Edwards Huntington was an American railroad magnate and collector of art and rare books. Huntington settled in Los Angeles, where he owned the Pacific Electric Railway as well as substantial real estate interests. In addition to being a businessman and art collector, Huntington was a major booster for Los Angeles in the late 19th and early 20th centuries. In the city of San Marino, many places are named after him, including a school, a road and a library. Born in Oneonta, New York, Henry Huntington was the nephew of Collis P. Huntington, one of The Big Four, instrumental in creating the Central Pacific Railroad, one of the two railroads that built the transcontinental railway in 1869. Henry Huntington held several executive positions alongside his uncle with the Southern Pacific. After Collis Huntington's death, Henry Huntington assumed Collis Huntington's leadership role with Newport News Shipbuilding and Drydock Company in Virginia, married his widow Arabella Huntington, his divorce from his first wife Mary Alice Prentice, birth sister of his Uncle Collis' adopted daughter, in 1910 and marriage to Arabella in 1913 after Mary Alice's death shocked San Francisco society.
He had none with Arabella. Arabella's son Archer, from her prior marriage from which she was widowed, had earlier been adopted by Collis Huntington. In 1898, in friendly competition with his uncle's Southern Pacific, Huntington bought the narrow gauge city-oriented Los Angeles Railway, known as the'Yellow Car' system. In 1901, Huntington formed the sprawling interurban, standard gauge Pacific Electric Railway, known as the'Red Car' system, centered at 6th and Main Streets in Los Angeles. Huntington succeeded in this competition by providing passenger friendly streetcars on 24/7 schedules, which the railroads could not match; this was facilitated by the boom in Southern California land development, where housing was built in places such as Orange County's Huntington Beach, a Huntington-sponsored development, streetcars served passenger needs that the railroads had not considered. Connectivity to Downtown Los Angeles made such suburbs feasible. By 1910, the Huntington trolley systems spanned 1,300 miles of southern California.
At its greatest extent, the system contained over 20 streetcar lines and 1,250 trolleys, most running through the core of Los Angeles and serving such nearby neighborhoods as the Crenshaw district, West Adams, Echo Park, Hancock Park, Exposition Park, Boyle Heights and Lincoln Heights. The system integrated the 1902 acquisition, the Mount Lowe Scenic Railway above Altadena, California in the San Gabriel Mountains. In 1905 Huntington, A. Kingsley Macomber, William R. Staats developed the Oak Knoll subdivision, located to the west of his San Marino estate in the oak-covered hilly terrain near Pasadena. In 1906, along with Frank Miller, owner of the Mission Inn, Charles M. Loring, formed the Huntington Park Association, with the intent to purchase Mount Rubidoux in Riverside, build a road to the summit, develop the hill as a park to benefit the city of Riverside; the road was completed in February 1907. The property was donated to the city of Riverside by the heirs of Frank Miller, today the hill is a 161-acre city park.
Huntington was a Life Member of the Sons of the Revolution in the State of California. Huntington retired from business in 1916. In 1927 Henry E. Huntington died in Philadelphia, he and Arabella are buried, with a large monument, in the Gardens of the Huntington Library in San Marino, California. The Huntington Hotel was named Hotel Wentworth when it opened on February 1, 1907. Financial problems and a disappointing first season forced it to close indefinitely. Henry Huntington purchased the Wentworth in 1911, it reopened in 1914, transformed into a winter resort. The 1920s were prosperous for the hotel, as Midwestern and Eastern entrepreneurs discovered California's warm winter climate; the hotel's reputation for fine service began with long-time general manager and owner Stephen W. Royce. By 1926, the hotel's success prompted Royce to open the property year-round; the "golden years" ended with the stock market crash and the Great Depression of the late 1920s and early 1930s. By the end of the 1930s the hotel was vibrant again.
When World War II began, all reservations were cancelled and the hotel was rented to the Army for $3,000 a month. Following the war, the Huntington's fortunes improved again. In 1954 Stephen Royce sold the hotel to the Sheraton Corporation, serving as general manager until his retirement in 1969; the hotel operated until 1985. The structure was built of un-reinforced concrete in 1906. After a two-and-a-half year major renovation, the hotel reopened in March 1991 as the Ritz Carlton Huntington Hotel and Spa; the hotel completed a $19 million renovation in January 2006. Huntington left a prominent legacy with the Huntington Library, Art Collections and Botanical Gardens on his former estate in San Marino near Pasadena. Other legacies in California include the cities of Huntington Beach and Huntington Park, as well as Huntington Lake. In greater Los Angeles are the Huntington Hospital in Pasadena, Henry E. Huntington Middle School in San Marino, the grand boulevard, Huntington Drive, running eastbound from downtown Los Angeles.
Its landscaped central parkway was the right-of-way for the Norther
Los Angeles Basin
The Los Angeles Basin is a sedimentary basin located in southern California, in a region known as the Peninsular Ranges. The basin is connected to an anomalous group of east-west trending chains of mountains collectively known as the California Transverse Ranges; the present basin is a coastal lowland area, whose floor is marked by elongate low ridges and groups of hills, located on the edge of the Pacific plate. The Los Angeles Basin, along with the Santa Barbara Channel, the Ventura Basin, the San Fernando Valley, the San Gabriel Basin, lies within the greater southern California region. On the north and east, the lowland basin is bound by the Santa Monica Mountains and Puente, Repetto hills. To the southeast, the basin is bordered by the San Joaquin Hills; the western boundary of the basin is marked by the Continental Borderland and is part of the onshore portion. The California borderland is characterized by north-west trending offshore basins; the Los Angeles Basin is notable for its great structural relief and complexity in relation to its geologic youth and small size for its prolific oil production.
Yerkes et al. identify 5 major stages of the basin's evolution that begins in the Upper Cretaceous and ends in the Pleistocene. This basin can be classified as an irregular pull-apart basin accompanied by rotational tectonics during the post-early Miocene. Before the formation of the basin, the area that encompasses the Los Angeles basin began above ground. A rapid transgression and regression of the shoreline moved the area to a shallow marine environment. Tectonic instability coupled with volcanic activity in subsiding areas during the Middle Miocene set the stage for the modern basin; the basin formed in a submarine environment and was brought back above sea level when the rate of subsidence slowed. There is much discussion in the literature about the geologic time boundaries when each basin forming event took place. While exact ages may not be clear, Yerkes et al. provided a general timeline to categorize the sequence of depositional events in the LA Basin's evolution and they are as follows: During pre-Turonian, metamorphosed sedimentary and volcanic rocks are present that serve as the two major basement rock units for the LA Basin.
Large-scale movement along the Newport–Inglewood zone juxtaposed the two bedrock units along the east and west margins. During this phase, the basin was above sea level; the hallmarks of this phase were successive shoreline regression cycles. Deposition of older marine and non-marine sediments began to fill the basin. Towards the end of this phase, the shoreline began to retreat and deposition continued. After the deposition of the pre-Turonian units, there was a large emergence and erosion that can be observed as a major unconformity at the base of the middle Miocene units. Emergence did not occur in all sections of the basin. During this time, the basin was covered by a marine embayment. Rivers sourced in the highlands brought large amounts of detritus to the northeastern edge of the basin. During this period, the Topanga formation was being deposited; the present form and structural relief of the basin was established during this phase of accelerated subsidence and deposition which occurred during the late Miocene and continued through the early Pleistocene.
Clastic sedimentary rocks from the highland areas moved down the submarine slopes and infilled the basin floor. Subsidence and sedimentation most began in the southern portion basin. Subsidence and Deposition occurred without interruption, until the late Pliocene; until the rate of deposition overtook the rate of subsidence, the sea level began to fall. Towards the end of this phase, the margins of the basin began to rise above sea level. During the early Pleistocene, deposition began to outpace subsidence in the depressed parts of the basin and the shoreline began to move southward; this phase had movement along the Newport–Inglewood fault zone that resulted in the initiation of the modern basin. This movement caused the southwestern block to be uplifted relative to the central basin block; the central part of the basin continued to experience sediment deposition through the Pleistocene from flooding and erosional debris from the surrounding mountains and Puente Hills. This infill was responsible for the final retreat of the shoreline from the basin.
Deposition in the Holocene is characterized by non marine gravel and silt. This phase includes the late stage compressional deformation responsible for the formation of the hydrocarbon traps. Four major faults are present in the region and divide the basin in the central, northwest and northeast structural blocks; these blocks not only denote their geographic location, but they indicate the strata present and major structural features. The southwestern block was uplifted prior to the middle Miocene and is composed of marine strata and contains two major anticlines; this block contains the steeply-dipping Palos Verdes Hills fault zone. The middle Miocene volcanics can be seen locally within the southwest block; the northwestern block consists of clastic marine sediments of Late Cretaceous to Pleistocene age. Middle Miocene volcanics are present; this block has a broad anticline, truncated by the Santa Monica fault zone. The central block contains both marine and non-marine clastic rock units interbedded with volcanic rocks that are late Cretaceous to Pliocene in age.
Pliocene and Quaternary strata are most visible within the central block. Structurally, there is a synclinal trough; the northeastern block contains fine to coarse grained clastic marine rocks of Cenozoic age. Locally, middle Mi
A summit is a point on a surface, higher in elevation than all points adjacent to it. The topographic terms acme, apex and zenith are synonymous; the term top is used only for a mountain peak, located at some distance from the nearest point of higher elevation. For example, a big massive rock next to the main summit of a mountain is not considered a summit. Summits near a higher peak, with some prominence or isolation, but not reaching a certain cutoff value for the quantities, are considered subsummits of the higher peak, are considered part of the same mountain. A pyramidal peak is an exaggerated form produced by ice erosion of a mountain top. Summit may refer to the highest point along a line, trail, or route; the highest summit in the world is Everest with height of 8844.43 m above sea level. The first official ascent was made by Sir Edmund Hillary, they reached the mountain`s peak in 1953. Whether a highest point is classified as a summit, a sub peak or a separate mountain is subjective; the UIAA definition of a peak is.
Otherwise, it's a subpeak. In many parts of the western United States, the term summit refers to the highest point along a road, highway, or railroad. For example, the highest point along Interstate 80 in California is referred to as Donner Summit and the highest point on Interstate 5 is Siskiyou Mountain Summit. A summit climbing differs from the common mountaineering. Summit expedition requires: 1+ year of training, a good physical shape, a special gear. Although a huge part of climber’s stuff can be left and taken at the base camps or given to porters, there is a long list of personal equipment. In addition to common mountaineers’ gear, Summit climbers need to take Diamox and bottles of oxygen. There are special requirements for crampons, ice axe, rappel device, etc. Geoid Hill – Landform that extends above the surrounding terrain Nadir Summit accordance Peak finder Summit Climbing Gear List