Cascade Range | |
---|---|
Highest point | |
Peak | Mount Rainier |
Elevation | 14,411 ft (4,392 m) |
Dimensions | |
Length | 700 mi (1,100 km) |
Geography | |
Countries | United States and Canada |
States | British Columbia, Washington, Oregon, and California |
Sierra Nevada | |
---|---|
Highest point | |
Peak | Mount Whitney |
Elevation | 14,505 ft (4,421 m) |
Dimensions | |
Length | 400 mi (640 km)north-south from Fredonyer Pass to Tehachapi Pass |
Width | 65 mi (105 km) |
Geography | |
Country | United States |
States | California and Nevada |
The Cascade-Sierra province is a physiographic region of mountains in the western United States, east and adjacent to Pacific Border province and west and adjacent to the Basin and Range Province (in the south) and Columbia Plateau Province (in the north).
The Cascade-Sierra province stretches approximately 1,000 mi (1,609.34 km) from the high desert region of the Mojave Desert in Southern California to just north of the border between British Columbia and the state of Washington. [1] [2]
The region is extremely diverse geologically and ecologically and is commonly divided into two regions: the Cascade Mountains and the Sierra Nevada Mountains. This province is part of a larger physiographic region that extends from Alaska in the north to the southern tip of South America. Several tectonic plates meet and form this region and make it one of the most geologically active places in North America. [3]
The province is home to several national forests, including the Lassen, Modoc, and Plumas National Forests. The Modoc Plateau, an area of high elevation basalt flows between the Medicine Lake Highlands and the Warner Mountains, is also within the region. The ecology of the province is extremely diverse and contains areas of pine, aspen, and cypress forests, mixed conifer and evergreen forests, along with montane meadows, fens, mammoth granite outcroppings, vernal pools, and sagebrush flats. [4]
The Cascade Mountains form the northern portion of the Cascade-Sierra province. The Cascades were created from thousands of small, short-lived volcanoes along the Cascadia subduction zone [5] that over millions of years built a foundation of lava and volcanic debris on which the mountains rise. This range includes thirteen major volcanic centers and are part of the Pacific Ocean's Ring of Fire. The two most recent eruptions are the Mount Lassen eruptions from 1914 to 1921, [6] and the Mount St. Helens eruption in 1980. [7]
The Sierra Nevada Mountains form the southern portion of the Cascade-Sierra province. Like the Cascade Range, the Sierra Nevada Range formed from a chain of volcanoes along a subduction zone. However unlike the Cascade volcanoes, those that formed the Sierra Nevada Range are mostly extinct and buried deep within the earth forming a bed of solidified lava that is responsible for the gray granitic rocks of the Sierra. One of the best known areas in the Sierra Nevada range is Yosemite National Park. [3] [4]
The Sierra Nevada is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily in Nevada. The Sierra Nevada is part of the American Cordillera, an almost continuous chain of mountain ranges that forms the western "backbone" of the Americas.
California is a U.S. state on the western coast of North America. Covering an area of 163,696 sq mi (423,970 km2), California is among the most geographically diverse states. The Sierra Nevada, the fertile farmlands of the Central Valley, and the arid Mojave Desert of the south are some of the geographic features of this U.S. state. It is home to some of the world's most exceptional trees: the tallest, most massive, and oldest. It is also home to both the highest and lowest points in the 48 contiguous states.
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 many of those in the North Cascades, and the notable volcanoes known as the High Cascades. The small part of the range in British Columbia is referred to as the Canadian Cascades or, locally, as the Cascade Mountains. The highest peak in the range is Mount Rainier in Washington at 14,411 feet (4,392 m).
The Ring of Fire is a tectonic belt of volcanoes and earthquakes.
The Pacific Coast Ranges are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico. Although they are commonly thought to be the westernmost mountain range of the continental United States and Canada, the geologically distinct Insular Mountains of Vancouver Island lie farther west.
Lava Beds National Monument is located in northeastern California, in Siskiyou and Modoc counties. The monument lies on the northeastern flank of Medicine Lake Volcano, which is the largest volcano by area in the Cascade Range.
Lassen Volcanic National Park is a national park of the United States in northeastern California. The dominant feature of the park is Lassen Peak, the largest plug dome volcano in the world and the southernmost volcano in the Cascade Range. Lassen Volcanic National Park is one of the few areas in the world where all four types of volcanoes can be found: plug dome, shield, cinder cone, and stratovolcano.
The Lassen volcanic area presents a geological record of sedimentation and volcanic activity in and around Lassen Volcanic National Park in Northern California, U.S. The park is located in the southernmost part of the Cascade Mountain Range in the Pacific Northwest region of the United States. Pacific Oceanic tectonic plates have plunged below the North American Plate in this part of North America for hundreds of millions of years. Heat and molten rock from these subducting plates has fed scores of volcanoes in California, Oregon, Washington and British Columbia over at least the past 30 million years, including these in the Lassen volcanic areas.
Lassen Peak, commonly referred to as Mount Lassen, is a 10,457 ft (3,187 m) lava dome volcano in Lassen Volcanic National Park in Northern California. Located in the Shasta Cascade region above the northern Sacramento Valley, it is the southernmost active volcano in the Cascade Range of the Western United States, and part of the Cascade Volcanic Arc stretching from southwestern British Columbia to northern California. It supports many flora and fauna among its diverse habitats, which reach high elevations and are subject to frequent snowfall.
Chaos Crags is the youngest group of lava domes in Lassen Volcanic National Park, California. They formed as six dacite domes 1,100-1,000 years ago, one dome collapsing during an explosive eruption about 70 years later. The eruptions at the Chaos Crags mark one of just three instances of Holocene activity within the Lassen volcanic center. The cluster of domes is located north of Lassen Peak and form part of the southernmost segment of the Cascade Range in Northern California. Each year, a lake forms at the base of the Crags, and typically dries by the end of the summer season.
The Shasta Cascade region of California is located in the northeastern and north-central sections of the state bordering Oregon and Nevada, including far northern parts of the Central Valley and the Sierra Nevada mountain range.
The richly textured landscape of the United States is a product of the dueling forces of plate tectonics, weathering and erosion. Over the 4.5 billion-year history of the Earth, tectonic upheavals and colliding plates have raised great mountain ranges while the forces of erosion and weathering worked to tear them down. Even after many millions of years, records of Earth's great upheavals remain imprinted as textural variations and surface patterns that define distinctive landscapes or provinces.
Lassen National Forest is a United States national forest of 1,700 square miles (4,300 km2) in northeastern California. It is named after pioneer Peter Lassen, who mined, ranched and promoted the area to emigrant parties in the 1850s.
The Pacific Ranges are the southernmost subdivision of the Coast Mountains portion of the Pacific Cordillera. Located entirely within British Columbia, Canada, they run northwest from the lower stretches of the Fraser River to Bella Coola and Burke Channel, north of which are the Kitimat Ranges. The Coast Mountains lie between the Interior Plateau and the Coast of British Columbia.
The North American Cordillera, sometimes also called the Western Cordillera of North America, the Western Cordillera, or the Pacific Cordillera, is the North American portion of the American Cordillera, the mountain chain system along the Pacific coast of the Americas. The North American Cordillera covers an extensive area of mountain ranges, intermontane basins, and plateaus in Western and Northwestern Canada, Western United States, and Mexico, including much of the territory west of the Great Plains.
The Mount Meager massif is a group of volcanic peaks in the Pacific Ranges of the Coast Mountains in southwestern British Columbia, Canada. Part of the Cascade Volcanic Arc of western North America, it is located 150 km (93 mi) north of Vancouver at the northern end of the Pemberton Valley and reaches a maximum elevation of 2,680 m (8,790 ft). The massif is capped by several eroded volcanic edifices, including lava domes, volcanic plugs and overlapping piles of lava flows; these form at least six major summits including Mount Meager which is the second highest of the massif.
The Cascade Volcanoes are a number of volcanoes in a volcanic arc in western North America, extending from southwestern British Columbia through Washington and Oregon to Northern California, a distance of well over 700 miles (1,100 km). The arc formed due to subduction along the Cascadia subduction zone. Although taking its name from the Cascade Range, this term is a geologic grouping rather than a geographic one, and the Cascade Volcanoes extend north into the Coast Mountains, past the Fraser River which is the northward limit of the Cascade Range proper.
The geology of the Pacific Northwest includes the composition, structure, physical properties and the processes that shape the Pacific Northwest region of North America. The region is part of the Ring of Fire: the subduction of the Pacific and Farallon Plates under the North American Plate is responsible for many of the area's scenic features as well as some of its hazards, such as volcanoes, earthquakes, and landslides.
The following outline is provided as an overview of and topical guide to the U.S. state of California:
The California Volcano Observatory (CalVO) is the volcano observatory that monitors the volcanic and geologic activity of California and Nevada. It is a part of the Volcano Hazards Program of the United States Geological Survey, a scientific agency of the United States government.