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30-541: This area is part of the basin and range geologic region, characterized by linear mountain ranges which are separated by broad, flat basins . The region was impacted by relatively recent volcanic activity, leaving volcanic plugs and cinder cones visible throughout the San Bernardino Valley . Earthquakes have further altered the region and helped allow the flow of many springs and seeps. All of these dynamic geological events have played major roles in shaping

60-514: A "principle of comprehensive analysis of the territory" and "Russian Chernozem ". In the latter, he introduced the geographical concept of soil, as distinct from a simple geological stratum, and thus found a new geographic area of study: pedology . Climatology also received a strong boost from the Russian school by Wladimir Köppen whose main contribution, climate classification, is still valid today. However, this great geographer also contributed to

90-406: A major development. Some of his disciples made significant contributions to various branches of physical geography such as Curtis Marbut and his invaluable legacy for Pedology, Mark Jefferson , Isaiah Bowman , among others. The compilation of Edrisi marks an era in the history of science . Not only is its historical information most interesting and valuable, but its descriptions of many parts of

120-400: 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 blocks sink down due to gravity, creating long linear valleys or basins also known as grabens , while the blocks remaining up or uplifted produce mountains or ranges, also known as horsts . Fault scarps are exposed on

150-468: Is another mountain lift and the cycle continues. Although Davis's theory is not entirely accurate, it was absolutely revolutionary and unique in its time and helped to modernize and create a geography subfield of geomorphology . Its implications prompted a myriad of research in various branches of physical geography. In the case of the Paleogeography, this theory provided a model for understanding

180-461: Is the most well known example of basin and range topography. Clarence Dutton 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 physiography of the province is the result of tectonic extension that began around 17 million years ago in the early Miocene epoch. Opinions vary regarding

210-659: The Hellenic Subduction Zone to the south, causing extensive normal faulting and the formation of horsts and grabens on the seafloor. Many of the islands are the result of peaks reaching above sea level. One of the most studied basin and range topographies is the Basin and Range Province in the western United States, located between the Sierra Nevada and the Rocky Mountains . The extension of

240-522: The Sierra Nevada microplate . Though the Aegean Sea Plate is more difficult to study because it is underwater, efforts have been made to conduct GPS surveys of the seafloor and surrounding area. Some studies show regions of extension within the plate, while others suggest a four-microplate model to represent the motion. The plate's deformation is thought to be a result of crustal collapse (beginning c. 14 Ma) combined with slab rollback on

270-428: The built environment , and technical geography , which focuses on using, studying, and creating tools to obtain, analyze, interpret, and understand spatial information. The three branches have significant overlap, however. Physical geography can be divided into several branches or related fields, as follows: Main category: Geography Journals Mental geography and earth science journals communicate and document

300-727: The Ancient Age. In more modern times, these works include the Alexander von Humboldt ( Kosmos ) in the nineteenth century, in which geography is regarded as a physical and natural science through the work Summa de Geografía of Martín Fernández de Enciso from the early sixteenth century, which indicated for the first time the New World. During the eighteenth and nineteenth centuries, a controversy exported from geology, between supporters of James Hutton (uniformitarianism thesis) and Georges Cuvier (catastrophism) strongly influenced

330-524: The Hellenic Subduction Zone. Physical geography Physical geography (also known as physiography ) is one of the three main branches of geography . Physical geography is the branch of natural science which deals with the processes and patterns in the natural environment such as the atmosphere , hydrosphere , biosphere , and geosphere . This focus is in contrast with the branch of human geography , which focuses on

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360-446: The area not only invaluable to a huge diversity of fish and wildlife, but also a center of human activity for centuries. With expanding settlement beginning in the late 19th century came farming , mining , and livestock production, all of which competed for the same precious water. While the extensive wetlands here once provided historic habitat for eight different kinds of native fish, the lowering water table led to severe changes in

390-553: The birth of geography as a science during the Greek classical period and until the late nineteenth century with the birth of anthropogeography (human geography), geography was almost exclusively a natural science: the study of location and descriptive gazetteer of all places of the known world. Several works among the best known during this long period could be cited as an example, from Strabo ( Geography ), Eratosthenes ( Geographika ) or Dionysius Periegetes ( Periegesis Oiceumene ) in

420-401: The evolution of the landscape. For hydrology, glaciology, and climatology as a boost investigated as studying geographic factors shape the landscape and affect the cycle. The bulk of the work of William Morris Davis led to the development of a new branch of physical geography: Geomorphology whose contents until then did not differ from the rest of geography. Shortly after this branch would present

450-617: The field of geography, because geography at this time was a natural science. Two historical events during the nineteenth century had a great effect on the further development of physical geography. The first was the European colonial expansion in Asia , Africa , Australia and even America in search of raw materials required by industries during the Industrial Revolution . This fostered the creation of geography departments in

480-491: The field to develop cycle of erosion theory which he proposed as a paradigm for geography in general, although in actually served as a paradigm for physical geography. His theory explained that mountains and other landforms are shaped by factors that are manifested cyclically. He explained that the cycle begins with the lifting of the relief by geological processes (faults, volcanism, tectonic upheaval, etc.). Factors such as rivers and runoff begin to create V-shaped valleys between

510-585: The habitat and the eventual local extinctions of many species. [REDACTED]  This article incorporates public domain material from websites or documents of the United States Fish and Wildlife Service . Basin and range 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

540-521: The horst block and expose the footwall of the normal fault. This is a type of block faulting known as grabens and horsts . This basin and range topography is symmetrical having equal slopes on both sides of the valleys and mountain ranges. Tilted block faulting , also known as half-graben or rotational block faulting, can also occur during extension. Large gently dipping normal faults, also known as detachment faults , act as platforms in which normal faulted blocks tilt or slide along. However, instead of

570-451: The mountains (the stage called "youth"). During this first stage, the terrain is steeper and more irregular. Over time, the currents can carve wider valleys ("maturity") and then start to wind, towering hills only ("senescence"). Finally, everything comes to what is a plain flat plain at the lowest elevation possible (called "baseline") This plain was called by Davis' " peneplain " meaning "almost plain" Then river rejuvenation occurs and there

600-406: The paleogeography through his work "The climates of the geological past" which is considered the father of paleoclimatology . Russian geographers who made great contributions to the discipline in this period were: NM Sibirtsev , Pyotr Semyonov , K.D. Glinka , Neustrayev , among others. The second important process is the theory of evolution by Darwin in mid-century (which decisively influenced

630-530: The patriarch of Russian geography, Mikhail Lomonosov . In the mid-1750s Lomonosov began working in the Department of Geography, Academy of Sciences to conduct research in Siberia. They showed the organic origin of soil and developed a comprehensive law on the movement of the ice, thereby founding a new branch of geography: glaciology . In 1755 on his initiative was founded Moscow University where he promoted

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660-490: The province was believed to have begun in the late Cenozoic Era, roughly 20 Ma . Between 1992 and 1998 scientists conducted GPS surveys to map the deformation of the Basin and Range province. In the study, Thatcher et al. discovered that most deformation was happening in the west, adjacent to the Sierra Nevada block, while less deformation was happening in the east. This coincides with the northwestward movement of

690-611: The results of research carried out in universities and various other research institutions. Most journals cover a specific publish the research within that field, however unlike human geographers, physical geographers tend to publish in inter-disciplinary journals rather than predominantly geography journal; the research is normally expressed in the form of a scientific paper . Additionally, textbooks, books, and communicate research to laypeople, although these tend to focus on environmental issues or cultural dilemmas. Examples of journals that publish articles from physical geographers are: From

720-567: The study of geography and the training of geographers. In 1758 he was appointed director of the Department of Geography, Academy of Sciences, a post from which would develop a working methodology for geographical survey guided by the most important long expeditions and geographical studies in Russia. The contributions of the Russian school became more frequent through his disciples, and in the nineteenth century we have great geographers such as Vasily Dokuchaev who performed works of great importance as

750-496: 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. With crustal extension ,

780-443: The total extension of the region; however, the median estimate is about 100% total lateral extension. The tectonic mechanisms responsible for lithospheric extension in the Basin and Range province are controversial, and several competing hypotheses attempt to explain them. The Aegean Sea Plate consists of thinned continental crust. The northern part of the plate is currently a region of crustal extension caused by slab rollback on

810-409: The universities of the colonial powers and the birth and development of national geographical societies, thus giving rise to the process identified by Horacio Capel as the institutionalization of geography. The exploration of Siberia is an example. In the mid-eighteenth century, many geographers were sent to perform geographical surveys in the area of Arctic Siberia . Among these is who is considered

840-401: The valley, catching and storing crucial water, helping determine the variety of plants and animals present. The San Bernardino Valley once supported permanently flowing creeks, springs, and marshy wetlands. In addition, the giant sacaton grassland in the valley was once described as "a luxuriant meadow some eight or ten miles long and a mile wide." The dependable source of water and grass made

870-408: The whole block subsiding only one side, the block may slip along the detachment fault, tilting toward the fault plane, again creating mountains (ranges) and valleys (basins), many tilted slightly in one direction at their tops due to the motion of their bottoms along the main detachment fault. This basin and range topography has one steep side and the other is more gradual. The Basin and Range Province

900-481: The work of Friedrich Ratzel , who had academic training as a zoologist and was a follower of Darwin's ideas) which meant an important impetus in the development of Biogeography. Another major event in the late nineteenth and early twentieth centuries took place in the United States . William Morris Davis not only made important contributions to the establishment of discipline in his country but revolutionized

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