The Aleutian Range is a major mountain range located in southwest Alaska. It extends from Chakachamna Lake to Unimak Island, which is at the tip of the Alaska Peninsula. It includes all of the mountains of the Peninsula. The Aleutian Range is special because of its large number of active volcanoes, which are also part of the larger Aleutian Arc. The mainland part of the range is about 600 miles (1000 km) long. The Aleutian Islands are (geologically) a partially submerged western extension of the range that stretches for another 1,600 km (1000 mi). However the official designation "Aleutian Range" includes only the mainland peaks and the peaks on Unimak Island. The range is almost entirely roadless wilderness. Katmai National Park and Preserve, a large national park within the range, must be reached by boat or plane.
Novarupta is a volcano that was formed in 1912, located on the Alaska Peninsula on a slope of Trident Volcano in Katmai National Park and Preserve, about 290 miles (470 km) southwest of Anchorage. Formed during the largest volcanic eruption of the 20th century, Novarupta released 30 times the volume of magma of the 1980 eruption of Mount St. Helens.
Mount Columbia is a mountain located in the Winston Churchill Range of the Rocky Mountains. It is the highest point in Alberta, Canada, and is second only to Mount Robson for height and topographical prominence in the Canadian Rockies. It is located on the border between Alberta and British Columbia on the northern edge of the Columbia Icefield. Its highest point, however, lies within Jasper National Park in Alberta.
Katmai National Park and Preserve is a United States national park and preserve in southwest Alaska, notable for the Valley of Ten Thousand Smokes and for its brown bears. The park and preserve encompass 4,093,077 acres, which is between the sizes of Connecticut and New Jersey. Most of the national park is a designated wilderness area. The park is named after Mount Katmai, its centerpiece stratovolcano. The park is located on the Alaska Peninsula, across from Kodiak Island, with headquarters in nearby King Salmon, about 290 miles (470 km) southwest of Anchorage. The area was first designated a national monument in 1918 to protect the area around the major 1912 volcanic eruption of Novarupta, which formed the Valley of Ten Thousand Smokes, a 40-square-mile (100 km2), 100-to-700-foot-deep pyroclastic flow. The park includes as many as 18 individual volcanoes, seven of which have been active since 1900.
Mount Katmai is a large active stratovolcano on the Alaska Peninsula in southern Alaska, located within Katmai National Park and Preserve. It is about 6.3 miles (10 km) in diameter with a central lake-filled caldera about two by three miles in size, formed during the Novarupta eruption of 1912. The caldera rim reaches a maximum elevation of 6,716 feet (2,047 m). In 1975 the surface of the crater lake was at an elevation of about 4,220 feet (1,286 m), and the estimated elevation of the caldera floor is about 3,400 ft (1,040 m). The mountain is located in Kodiak Island Borough, very close to its border with Lake and Peninsula Borough. The volcano has caused ten known fatalities due to gas exposure.
Mount Hubbard is one of the major mountains of the Saint Elias Range. It is located on the Alaska/Yukon border; the Canadian side is within Kluane National Park and Reserve, and the American side is part of Wrangell–St. Elias National Park. The mountain was named in 1890 by U.S. Geological Survey geologist Israel Russell after Gardiner Greene Hubbard, first president of the National Geographic Society, which had co-sponsored Russell's expedition.
Mount Gibbs is located in the Sierra Nevada of the U.S. state of California, 2.6 miles (4 km) south of Mount Dana. The mountain was named in honor of Oliver Gibbs, a professor at Harvard University and friend of Josiah Whitney. The summit marks the boundary between Yosemite National Park and the Ansel Adams Wilderness, and Mount Gibbs is the sixth-highest mountain, of Yosemite.
Mount Nirvana, at 2,773 m (9,098 ft) is the unofficial name of the highest mountain in the Northwest Territories, Canada. The mountain is a part of Nahanni National Park Reserve, the largest national park in the Northwest Territories.
Mount Sanford is a shield volcano in the Wrangell Volcanic Field, in eastern Alaska near the Copper River. It is the sixth highest mountain in the United States and the third highest volcano behind Mount Bona and Mount Blackburn. The south face of the volcano, at the head of the Sanford Glacier, rises 8,000 feet (2,400 m) in 1 mile (1,600 m) resulting in one of the steepest gradients in North America.
Mount Griggs, formerly known as Knife Peak Volcano, is a stratovolcano, which lies 10 km behind the volcanic arc defined by other Katmai group volcanoes. Although no historic eruptions have been reported from Mount Griggs, vigorously active fumaroles persist in a summit crater and along the upper southwest flank. The fumaroles on the southwest flank are the hottest, and some of the flank fumaroles can roar so loudly that they can be heard from the valley floor. The slopes of Mount Griggs are heavily mantled by fallout from the 1912 eruption of Novarupta volcano. The summit consists of three concentric craters, the lowest and largest of which contains a recent summit cone topped by two craters. The volume of the volcanic edifice is estimated at 25 cubic kilometers (6.0 cu mi). Isotopic analysis indicates that the source of Griggs' magma is distinct from the other Katmai volcanoes.
Mount Martin is a stratovolcano, located on the Alaska Peninsula, United States, in Katmai National Park and Preserve. It is one of the volcanoes in the vicinity of the Valley of Ten Thousand Smokes. Mount Martin's cone stands only about 500 metres (1,600 ft) higher than the surrounding ridge. Although an eruption in 1953 is now considered questionable and no other confirmed eruptive activity has taken place at Mount Martin, there is intense fumarolic activity within its summit crater. The summit crater is also breached to the southeast. The 300 m (984 ft)-wide summit crater is often ice-free due to the geothermal heat and contains an intermittent acidic crater lake. The fumaroles in the summit crater produce extensive sulfur deposits.
Robert Fiske Griggs, was a botanist who led a 1915 National Geographic Society (NGS) expedition to observe the aftermath of the Katmai volcanic eruption.
Mount Bona is one of the major mountains of the Saint Elias Mountains in eastern Alaska, and is the fifth-highest independent peak in the United States. It is either the tenth- or eleventh-highest peak in North America. Mount Bona and its adjacent neighbor Mount Churchill are both large ice-covered stratovolcanoes. Bona has the distinction of being the highest volcano in the United States and the fourth-highest in North America, outranked only by the three highest Mexican volcanoes, Pico de Orizaba, Popocatépetl, and Iztaccíhuatl. Its summit is a small stratovolcano on top of a high platform of sedimentary rocks.
Mount Jefferson is the highest mountain in both the Toquima Range and Nye County in Nevada, United States. It is the sixth highest mountain in the state. As the high point of a range which is well separated from other ranges by low basins, Mount Jefferson has a high topographic prominence of 5,861 feet (1,786 m). This makes it the most prominent peak in Nye County and the third most prominent peak in Nevada. For similar reasons, it is also the highest mountain for over 90 miles in all directions. It is located about 50 miles (80 km) northeast of the county seat of Tonopah within the Alta Toquima Wilderness of the Humboldt-Toiyabe National Forest, near the smaller towns of Carvers and Round Mountain. Three distinct summits are located on a broad area of subalpine tundra: North Summit rises to 11,820 feet (3,603 m), Middle Summit to 11,692 feet (3,564 m), and South Summit to 11,949 feet (3,642 m). During the Pleistocene, alpine glaciers eroded several cirques east of the summit plateau.
The Alaska Volcano Observatory (AVO) is a joint program of the United States Geological Survey (USGS), the Geophysical Institute of the University of Alaska Fairbanks (UAFGI), and the State of Alaska Division of Geological and Geophysical Surveys (ADGGS). AVO was formed in 1988, and uses federal, state, and university resources to monitor and study Alaska's volcanology, hazardous volcanoes, to predict and record eruptive activity, and to mitigate volcanic hazards to life and property. The Observatory website allows users to monitor active volcanoes, with seismographs and webcameras that update regularly. AVO now monitors more than 20 volcanoes in Cook Inlet, which is close to Alaskan population centers, and the Aleutian Arc due to the hazard that plumes of ash pose to aviation.
Mount Isto is the highest peak in the Brooks Range, Alaska, USA. Located in the eastern Brooks Range, in what are known as the Romanzof Mountains, Mount Isto is 5 miles (8.0 km) south of Mount Hubley, the second tallest peak in the Brooks Range. Mount Isto is within the Arctic National Wildlife Refuge and was named in 1966 for Reynold E. (Pete) Isto, a civil engineer for the U.S. Geological Survey. In 2014, new measurement technology established that Mount Isto is the highest peak in the Brooks Range. Previously, Mount Chamberlin was believed to be the tallest, but it is now ranked third.
