Alaska Range

The Alaska Range is a relatively narrow, 650-km-long (400 mi) mountain range in the southcentral region of the U.S. state of Alaska, from Lake Clark at its southwest end to the White River in Canada's Yukon Territory in the southeast. The highest mountain in North America, Mount McKinley (or Denali), is in the Alaska Range.

Appalachian Mountains

The Appalachian Mountains, often called the Appalachians, are a vast system of mountains in eastern North America. The Appalachians are believed to have been the highest mountains on earth roughly 460 million years ago during the Ordovician Period, much like (but higher than[citation needed]) the Himalayas today, when all of today's continents were joined as the supercontinent Pangaea. The Appalachian chain is a barrier to east-west travel as it forms a series of alternating ridgelines and valleys oriented in opposition to any road running east-west.

The Appalachian Mountains represent a series of Paleozoic orogenies along the eastern margin of North America. The Appalachians extend from Alabama through Maine in the United States, and continue across the southeastern provinces of Canada to Newfoundland. More than 10,000 m of Paleozoic sedimentary and volcanic strata are contained in the exposed portions of the Appalachian Mountains, about 10 times the thickness of equivalent strata in the mid-continent region. The Appalachian Mountains are divided classically into four main provinces, which are best developed from New York southward.

Piedmont -- Stretching from Alabama to New York, the Piedmont is a plateau of moderate elevation (150-300 m) that forms the eastern portion of the mountain system. It consists of varied crystalline metamorphic and igneous rocks of Paleozoic age. Many of the rocks began as marine sediments and volanic deposits--typical oceanic crust--that were deformed and metamorphosed mostly to the greenschist facies of chlorite and biotite schists and slate. Numerous granite intrusions form domes within the Piedmont, and narrow belts of serpentine are common. All Paleozoic and older rocks of the Piedmont Province are now thought to be completely allochthonous thrust masses.

Blue Ridge -- Upthrust Proterozoic basement rocks form a relatively narrow ridge separating the Piedmont from the Valley and Ridge provinces. The boundary between the Piedmont and Blue Ridge is marked by the Brevard Fault zone in the southern Appalachian. This fault zone contains remnants of unmetamorphosed sedimentary rocks derived from the deep décollement beneath the Piedmont Province. Like the Piedmont, the Blue Ridge is considered to be allochthonous.

Valley and Ridge -- Paleozoic sedimentary rocks are thrust and folded into large anticlines and synclines. This deformation took place at low temperature over shallow décollements (shale, salt) within the sedimentary sequence. Metamorphic and igneous rocks are conspicuously absent. Differential erosion of the thrust and folded structures has led to the distinctive valley-and-ridge topography for which this province is famous. Deformation diminishes westward in a transition into the Appalachian Plateau.

Appalachian Plateau -- The plateau is underlain by gently folded to little-deformed Paleozoic sedimentary strata. The amplitude of folding and thickness of strata decrease toward the continental interior. Deep stream entrenchment has created a rugged topography, which was the main geographic barrier to westward expansion of the early United States.

External link: http://academic.emporia.edu/aberjame/struc_geo/appalach/appalach.htm

Brooks Range

The Brooks Range is a mountain range in far northern North America. It stretches from west to east across northern Alaska and into Canada's Yukon Territory, a total distance of about 1100 km (700 mi). The mountains top out at over 2,700 m (9,000 ft). The range is believed to be approximately 126 million years old. These mountains are considered part of (or an extension of) the Rockies.[1][2]

The range is mostly uninhabited, but the Dalton Highway and the Trans-Alaska Pipeline System run through the Atigun Pass (1,415 m, 4,643 ft) on their way to the North Slope and the oil fields at Prudhoe Bay. The Alaska Native villages of Anaktuvuk and Arctic Village, as well as the very small communities of Coldfoot, Wiseman, Bettles, and Chandalar Lake are the only settlements in the 700-mile Brooks Range. In the far west, near the Wulik River in the De Long Mountains is the Red Dog mine, largest zinc mine in the world.

The range was named by the United States Board on Geographic Names in 1925 after Alfred Hulse Brooks, who was the chief USGS geologist for Alaska from 1903 to 1924.

Various historical records also referred to the range as the Arctic Mountains, Hooper Mountains, Meade Mountains and Meade River Mountains; the Canadian portion is still often referred to as the British Mountains. The British Mountains are part of Ivvavik National Park.

Canadian Shield

The Canadian Shield, also called the Laurentian Plateau, or Bouclier canadien (French), is a vast geological shield covered by a thin layer of soil that forms the nucleus of the North American or Laurentia craton. It is an area mostly composed of igneous rock which relates to its long volcanic history. It has a deep, common, joined bedrock region in eastern and central Canada and stretches North from the Great Lakes to the Arctic Ocean, covering over half of Canada; it also extends south into the northern reaches of the United States. Human population is scarce, and industrial development is minimal, while mining is very prevalent.

Cascades

The Cascade Range (or Cascades) is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades. The small part of the range in British Columbia is locally called the "Coastal Mountains" but is also known as the Canadian Cascades or Cascade Mountains; the latter term is also sometimes used by Washington residents to refer to the Washington section of the Cascades in addition to North Cascades, the more usual American term, as in North Cascades National Park.

The Cascades are part of the Pacific Ring of Fire, the ring of volcanoes and associated mountains around the Pacific Ocean. All of the known historic eruptions in the contiguous United States have been from Cascade volcanoes. The two most recent were Lassen Peak in 1914 to 1921 and a major eruption of Mount St. Helens in 1980. Minor eruptions of Mount St. Helens have also occurred since, most recently in 2006.

Coast Range

The Coast Mountains are a major mountain range, in the Pacific Coast Ranges, of western North America, extending from southwestern Yukon through the Alaska Panhandle and virtually all of the Coast of British Columbia. They are so-named because of their proximity to the sea coast, and are often referred to as the Coast Range. It includes volcanic and non-volcanic mountains and the huge icefields of the Pacific and Boundary Ranges, and the northern end of the notable volcanic system known as the Cascade Volcanoes. The Coast Mountains are part of a larger mountain system called the Pacific Coast Ranges or the Pacific Mountain System, which includes the Cascade Range, the Insular Mountains, the Oregon and California Coast Ranges and the Saint Elias and Chugach Mountains.

The Coast Mountains are approximately 1,600 kilometres (990 mi) long and average 300 kilometres (190 mi) in width. Its southern and southeastern boundaries are surrounded by the Fraser River and the Interior Plateau while its far northwestern edge is delimited by the Kelsall and Tatshenshini Rivers at the north end of the Alaska Panhandle, beyond which are the Saint Elias Mountains, and by Champagne Pass in the Yukon Territory. Covered in dense temperate rainforest on its western exposures, the range rises to heavily glaciated peaks, including the largest temperate-latitude icefields in the world. It then tapers to the dry Interior Plateau on its eastern flanks, or to the subarctic boreal forest of the Skeena Mountains and Stikine Plateau.

The Coast Mountains are part of the Pacific Ring of Fire, the ring of volcanoes and associated mountains around the Pacific Ocean. It contains some of British Columbia's highest mountains. Mount Waddington, northeast of the head of Knight Inlet with an elevation of 4,019 metres (13,186 ft), is the highest mountain of the Coast Mountains and the highest that lies entirely within British Columbia.

Coastal Plain

A coastal plain is an area of flat, low-lying land adjacent to a seacoast and separated from the interior by other features. One of the world's longest coastal plains is located in eastern South America. The southwestern coastal plain of North America is notable for its species diversity. The Gulf Coastal Plain of North America extends northwards from the Gulf of Mexico along the Lower Mississippi River to the Ohio River, which is a distance of about 500 miles (about 800 km). During the Cretaceous age, the central area of the United States was covered by a shallow sea, which disappeared as the land rose. Large fossilized aquatic birds called Hesperornis and Ichthyornis, found in western Kansas, indicate that the shallow sea was rife with fish. The coastal plain lying alongside the lower Mississippi River may be associated with a shallow sea which had existed 6 thousand years ago.

Great Plains

The Great Plains are a broad expanse of flat land, much of it covered in prairie, steppe and grassland, which lies west of the Mississippi River and east of the Rocky Mountains in the United States and Canada. This area covers parts of the U.S. states of Colorado, Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, South Dakota, Texas, and Wyoming, and the Canadian provinces of Alberta, Manitoba and Saskatchewan. The Canadian portion of the Plains is known as the Prairies. Some geographers include some territory of Mexico in the Plains, but many stop at the Rio Grande.

Rocky Mountains

The Rocky Mountains (or the Rockies) are a major mountain range in western North America. The Rocky Mountains stretch more than 3,000 miles (4,830 km) from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States. The range's highest peak is Mount Elbert located in Colorado at 14,440 feet (4,401 m) above sea level. Within the North American Cordillera, the Rockies are somewhat distinct from the Pacific Coast Ranges and the Cascade Range and Sierra Nevada which all lie further to the west.

The Rocky Mountains were formed from 80 million to 55 million years ago by the Laramide orogeny. Since then, erosion by water and glaciers has sculpted the mountain range into dramatic valleys and peaks. At the end of the last ice age, humans started to inhabit the mountain range. After Europeans, such as Sir Alexander MacKenzie and the Lewis and Clark expedition, started to explore the range, minerals and furs drove the initial economic exploitation of the mountains, although the range itself never became densely populated.

Currently, much of the mountain range is protected by public parks and forest lands, and is a popular tourist destination, especially for hiking, camping, mountaineering, fishing, hunting, skiing, and snowboarding.

Sierra Nevada

The Sierra Nevada (Spanish: [ˈsjera neˈβaða], snowy mountain range) is a mountain range in the U.S. states of California and Nevada, between the California Central Valley and the Basin and Range Province. The Sierra runs 400 miles (640 km) north-to-south, and is approximately 70 miles (110 km) across east-to-west. Notable Sierra features include Lake Tahoe, the largest alpine lake in North America; Mount Whitney at 14,505 feet (4,421 m), the highest point in the contiguous United States; and Yosemite Valley sculpted by glaciers out of 100-million-year-old granite. The Sierra is home to three national parks, 20 wilderness areas, and two national monuments. These areas include Yosemite, Sequoia and Kings Canyon National Parks.

The character of the range is shaped by its geology and ecology. More than 100 million years ago, granite formed deep underground. The range started to uplift 4 million years ago, and erosion by glaciers exposed the granite and formed the light-colored mountains and cliffs that make up the range. The uplift caused a wide range of elevations and climates in the Sierra, which are reflected by the presence of five life zones.

The Sierra Nevada was home to several Native American tribes. The range was first sighted by Pedro Fages in 1772, and then explored between 1844 and 1912.

Sierra Madres

The Sierra Madre Mountains are a mountain range in northern Santa Barbara County, California, USA. They are a portion of the Inner South Coast Ranges, representing the southernmost part, which are themselves part of the Pacific Coast Ranges of western North America. The Sierra Madre Mountains trend from northwest to southeast, and are approximately 25 mi (40 km) long. High peaks in the range include MacPherson Peak (5,747 feet (1,752 m)), and the highest point in the range, Peak Mountain (5,843 feet (1,781 m)). To the southeast, the range merges with the San Rafael Mountains in a complex topography of unnamed ranges, the highest point of which is Big Pine Mountain (6,820 ft (2,079 m)), the highest point in Santa Barbara County. Snow falls on the highest peaks during the winter months.

The Sierra Madre Mountains are almost entirely within the Los Padres National Forest, and mark the northern boundary of the San Rafael Wilderness. The southeastern extent of the range is about 25 mi (40 km) north of the city of Santa Barbara, and the northwestern extent of the range is about 50 mi (80 km) north by northwest of the city.

Las Coches Mountain in the Sierra Madre Mountains, from SR166. The predominant vegetation type on the mountains is chaparral; however oak woodlands occur in some areas, and some of the higher slopes support small areas of coniferous forest. The mountains are one of the most important habitat areas of the endangered California Condor.

Geologically, the mountains are almost entirely composed of sedimentary rocks of Tertiary age. Most of the rocks are Eocene marine sandstones and other sediments, and one region in the eastern portion of the range is made up of middle and early Miocene sediments. The mountain range is delineated on the south by the Nacimiento Fault, and on the north, by the South Cuyama and Ozena Faults. The Sierra Madre Mountains rise abruptly just south of the Cuyama Valley, which defines the northern boundary of Santa Barbara County.

The mountain range is almost entirely uninhabited, except for portions of the lower slopes to the north, which is developed for oil and gas production at the South Cuyama Oil Field. One difficult, single-lane dirt road follows the mountain crest; it often is closed after storms, and is normally only passable by four-wheel-drive vehicles or motorcycles.