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24-467: Peach Bottom Township was so named on account of peach trees growing near a river bottom . Peach Bottom Nuclear Generating Station was built in 1958. The Coulsontown Cottages Historic District , Delta Trestle Bridge, Maryland and Pennsylvania Railroad , and Scott Creek Bridge-North, Maryland and Pennsylvania Railroad are listed on the National Register of Historic Places . According to

48-473: A plain based on elevation above sea level . In studies of the ecology of freshwater rivers , habitats are classified as upland or lowland. Upland and lowland are portions of a plain that are conditionally categorized by their elevation above the sea level . Lowlands are usually no higher than 200 m (660 ft), while uplands are somewhere around 200 m (660 ft) to 500 m (1,600 ft). On unusual occasions, certain lowlands such as

72-1040: A riffle and pool structure and cooler water temperatures. Rivers with a course that drops in elevation very slowly will have slower water flow and lower force. This in turn produces the other characteristics of a lowland river—a meandering course lacking rapids , a river bed dominated by fine sediments and higher water temperatures. Lowland rivers tend to carry more suspended sediment and organic matter as well, but some lowland rivers have periods of high water clarity in seasonal low-flow periods. The generally clear, cool, fast-flowing waters and bedrock and coarse sediment beds of upland rivers encourage fish species with limited temperature tolerances, high oxygen needs, strong swimming ability and specialised reproductive strategies to prevent eggs or larvae being swept away. These characteristics also encourage invertebrate species with limited temperature tolerances, high oxygen needs and ecologies revolving around coarse sediments and interstices or "gaps" between those coarse sediments. The term "upland"

96-843: 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 , the Aleutian Range , on through Kamchatka Peninsula , Japan , Taiwan , the Philippines , Papua New Guinea , to New Zealand . The Andes

120-722: Is 7,000 kilometres (4,350 mi) long and is often considered the world's longest mountain system. The Alpide belt stretches 15,000 km across southern Eurasia , from Java in Maritime Southeast Asia to the Iberian Peninsula in Western Europe , including the ranges of the Himalayas , Karakoram , Hindu Kush , Alborz , Caucasus , and the Alps . The Himalayas contain the highest mountains in

144-476: Is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have arisen from the same cause, usually 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 also found on many planetary mass objects in

168-727: Is also used in wetland ecology , where "upland" plants indicate an area that is not a wetland. The generally more turbid , warm, slow-flowing waters and fine sediment beds of lowland rivers encourage fish species with broad temperature tolerances and greater tolerances to low oxygen levels, and life history and breeding strategies adapted to these and other traits of lowland rivers. These characteristics also encourage invertebrate species with broad temperature tolerances and greater tolerances to low oxygen levels and ecologies revolving around fine sediments or alternative habitats such as submerged woody debris ("snags") or submergent macrophytes ("water weed"). Lowland alluvial plains form when there

192-538: 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 (3,000 m) of mostly 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

216-668: Is deposition of sediment over a long period of time by one or more rivers coming from highland regions, and then are deposited in lowland regions for long periods of time. Examples include American Bottom , a flood plain of the Mississippi River in Southern Illinois, Bois Brule Bottom , and Bottomland hardwood forest a deciduous hardwood forest found in broad lowland floodplains of the United States. Mountain ranges A mountain range or hill range

240-531: Is drier, having been stripped of much of its moisture. Often, a rain shadow will affect the leeward side of a range. As a consequence, large mountain ranges, such as the Andes, compartmentalize continents into distinct climate regions . Mountain ranges are constantly subjected to erosional forces which work to tear them down. The basins adjacent to an eroding mountain range are then filled with sediments that are buried and turned into sedimentary rock . Erosion

264-453: Is frequently colored by sediment and organic matter. These classifications overlap with the geological definitions of "upland" and "lowland". In geology an "upland" is generally considered to be land that is at a higher elevation than the alluvial plain or stream terrace , which are considered to be "lowlands". The term "bottomland" refers to low-lying alluvial land near a river. Much freshwater fish and invertebrate communities around

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288-433: Is not the sole determinant of whether a river is upland or lowland. Arguably the most important determinants are those of stream power and stream gradient . Rivers with a course that drops rapidly in elevation will have faster water flow and higher stream power or "force of water". This in turn produces the other characteristics of an upland river—an incised course , a river bed dominated by bedrock and coarse sediments,

312-574: The Caspian Depression lie below sea level. Uplands areas tend to spike into valleys and mountains , forming mountain ranges while lowland areas tend to be uniformly flat, although both can vary such as the Mongolian Plateau . Upland habitats are cold, clear and rocky whose rivers are fast-flowing in mountainous areas; lowland habitats are warm with slow-flowing rivers found in relatively flat lowland areas, with water that

336-473: The Ocean Ridge forms the longest continuous mountain system on Earth, with a length of 65,000 kilometres (40,400 mi). The position of mountain ranges influences climate, such as rain or snow. When air masses move up and over mountains, the air cools, producing orographic precipitation (rain or snow). As the air descends on the leeward side, it warms again (following the adiabatic lapse rate ) and

360-519: The Solar System and are likely a feature of most terrestrial planets . Mountain ranges are usually segmented by highlands or mountain passes and valleys . Individual mountains within the same mountain range do not necessarily 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, and volcanic landforms resulting in

384-693: The United States Census Bureau , the township has a total area of 29.6 square miles (77 km), of which 29.2 square miles (76 km) is land and 0.4 square miles (1.0 km), or 1.28%, is water. The southern boundary of the township is the Maryland -Pennsylvania border (the Mason–Dixon Line ), and the eastern border is the Susquehanna River . The township surrounds on three sides the borough of Delta , located along

408-399: The average family size was 3.20. In the township the population was spread out, with 29.2% under the age of 18, 6.3% from 18 to 24, 33.7% from 25 to 44, 21.3% from 45 to 64, and 9.5% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 106.9 males. For every 100 females age 18 and over, there were 106.5 males. The median income for a household in

432-485: The east. This mass of rock was removed as the range was actively undergoing uplift. The removal of such a mass from the core of the range most likely 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,

456-408: The population. There were 1,528 households, out of which 42.0% had children under the age of 18 living with them, 67.1% were married couples living together, 6.5% had a female householder with no husband present, and 20.4% were non-families. 16.4% of all households were made up of individuals, and 6.4% had someone living alone who was 65 years of age or older. The average household size was 2.87 and

480-627: 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, including the Moon , are often isolated and formed mainly by processes such as impacts, though there are examples of mountain ranges (or "Montes") somewhat similar to those on Earth. Saturn 's moon Titan and Pluto , in particular, exhibit large mountain ranges in chains composed mainly of ices rather than rock. Examples include

504-523: The state line. As of the census of 2000, there were 4,412 people, 1,528 households, and 1,216 families living in the township. The population density was 151.0 inhabitants per square mile (58.3/km). There were 1,852 housing units at an average density of 63.4 per square mile (24.5/km). The racial makeup of the township was 96.60% White , 1.99% African American , 0.36% Native American , 0.32% Asian , 0.09% from other races , and 0.63% from two or more races. Hispanic or Latino of any race were 0.57% of

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528-556: The township was $ 42,778, and the median income for a family was $ 45,753. Males had a median income of $ 35,043 versus $ 24,468 for females. The per capita income for the township was $ 17,005. About 2.5% of families and 3.9% of the population were below the poverty line , including 2.4% of those under age 18 and 2.8% of those age 65 or over. 39°44′00″N 76°17′59″W  /  39.73333°N 76.29972°W  / 39.73333; -76.29972 Bottomland (freshwater ecology) Upland and lowland are conditional descriptions of

552-531: The world show a pattern of specialization into upland or lowland river habitats. Classifying rivers and streams as upland or lowland is important in freshwater ecology , as the two types of river habitat are very different, and usually support very different populations of fish and invertebrate species. In freshwater ecology, upland rivers and streams are the fast-flowing rivers and streams that drain elevated or mountainous country, often onto broad alluvial plains (where they become lowland rivers). However, elevation

576-543: The world, including Mount Everest , which is 8,848 metres (29,029 ft) high. Mountain ranges outside these two systems include the Arctic Cordillera , Appalachians , Great Dividing Range , East Siberians , Altais , Scandinavians , Qinling , Western Ghats , Vindhyas , Byrrangas , and the Annamite Range . If the definition of a mountain range is stretched to include underwater mountains, then

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