A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
Crater Lake National Park is an American national park located in southern Oregon. Established in 1902, Crater Lake is the fifth-oldest national park in the United States and the only national park in Oregon. The park encompasses the caldera of Crater Lake, a remnant of Mount Mazama, a destroyed volcano, and the surrounding hills and forests.
Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption. Types of volcanic cones include stratocones, spatter cones, tuff cones, and cinder cones.
A shield volcano is a type of volcano usually composed almost entirely of fluid lava flows. It is named for its low profile, resembling a warrior's shield lying on the ground. This is caused by the highly fluid lava erupted, which travels farther than lava erupted from a stratovolcano, and results in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form.
The Mono–Inyo Craters are a volcanic chain of craters, domes and lava flows in Mono County, Eastern California. The chain stretches 25 miles (40 km) from the northwest shore of Mono Lake to the south of Mammoth Mountain. The Mono Lake Volcanic Field forms the northernmost part of the chain and consists of two volcanic islands in the lake and one cinder cone volcano on its northwest shore. Most of the Mono Craters, which make up the bulk of the northern part of the Mono–Inyo chain, are phreatic volcanoes that have since been either plugged or over-topped by rhyolite domes and lava flows. The Inyo volcanic chain form much of the southern part of the chain and consist of phreatic explosion pits, and rhyolitic lava flows and domes. The southernmost part of the chain consists of fumaroles and explosion pits on Mammoth Mountain and a set of cinder cones south of the mountain; the latter are called the Red Cones.
Kīlauea is an active shield volcano in the Hawaiian Islands. Historically, it is the most active of the five volcanoes that together form the Big Island of Hawaiʻi. Located along the southeastern shore of the island, the volcano is between 210,000 and 280,000 years old and emerged above sea level about 100,000 years ago. Its most recent eruption began on December 20, 2020.
Mount Mazama is a complex volcano in the state of Oregon, United States, in a segment of the Cascade Volcanic Arc and Cascade Range. Most of the mountain collapsed following a major eruption approximately 7,700 years ago. The volcano is in Klamath County, in the southern Cascades, 60 miles (97 km) north of the Oregon-California border. Its collapse formed a caldera that holds Crater Lake. The mountain is in Crater Lake National Park. Mount Mazama originally had an elevation of 12,000 feet (3,700 m), but following its climactic eruption this was reduced to 8,157 feet (2,486 m). Crater Lake is 1,943 feet (592 m) deep, the deepest freshwater body in the US and the second deepest in North America after Great Slave Lake in Canada.
Mount Katmai is a large 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.
Belknap Crater is a shield volcano in the Cascade Range in the U.S. state of Oregon. Located in Linn County, it is associated with lava fields and numerous subfeatures including the Little Belknap and South Belknap volcanic cones. It lies north of McKenzie Pass and forms part of the Mount Washington Wilderness. Belknap is not forested and most of its lava flows are not vegetated, though there is some wildlife in the area around the volcano, as well as a number of tree molds formed by its eruptive activity.
Ambrym is a volcanic island in Malampa Province in the archipelago of Vanuatu. Volcanic activity on the island includes lava lakes in two craters near the summit.
Masaya is a caldera located in Masaya, Nicaragua, 20 km south of the capital Managua. It is Nicaragua's first and largest national park, and one of 78 protected areas of Nicaragua. The complex volcano is composed of a nested set of calderas and craters, the largest of which is Las Sierras shield volcano and caldera. Within this caldera lies a sub-vent, which is Masaya Volcano sensu stricto. The vent is a shield type composing of basaltic lavas and tephras and includes a summit crater. This hosts Masaya caldera, formed 2,500 years ago by an 8-km³ basaltic ignimbrite eruption. Inside this caldera a new basaltic complex has grown from eruptions mainly on a semi-circular set of vents that include the Masaya and Nindiri cones. The latter host the pit craters of Masaya, Santiago, Nindiri and San Pedro. Observations in the walls of the pit craters indicate that there have been several episodes of cone and pit crater formation.
Mount Kaguyak is a stratovolcano located in the northeastern part of the Katmai National Park and Preserve in the U.S. state of Alaska. The 2.5 km wide caldera is filled by a more than 180 m deep crater lake. The surface of the crater lake lies about 550 m below the rim of the caldera. Postcaldera lava domes form a prominent peninsula in the center of the lake. The volcano is 901 metres (2,956 ft) high and is topographically prominent because it rises from lowland areas near sea level in the south of the Big River. Based on radiocarbon dating the caldera-forming eruption occurred about 5800 years before present. During this eruption at least 120 km2 (46 sq mi) were covered in a dacitic ignimbrite.
Mount Okmok is the highest point on the rim of Okmok Caldera on the northeastern part of Umnak Island in the eastern Aleutian Islands of Alaska. This 9.3 kilometers (5.8 mi) wide circular caldera truncates the top of a large shield volcano. The volcano is currently rated by the Alaska Volcano Observatory as Aviation Alert Level Green and Volcanic-alert Level Normal.
Mount Longonot is a stratovolcano located southeast of Lake Naivasha in the Great Rift Valley of Kenya, Africa. It is thought to have last erupted in the 1860s. Its name is derived from the Maasai word Oloonong'ot, meaning "mountains of many spurs" or "steep ridges".
A rootless cone, also formerly called a pseudocrater, is a volcanic landform which resembles a true volcanic crater, but differs in that it is not an actual vent from which lava has erupted. They are characterised by the absence of any magma conduit which connects below the surface of a planet.
Wizard Island is a volcanic cinder cone which forms an island at the west end of Crater Lake in Crater Lake National Park, Oregon. The top of the island reaches 6,933 feet (2,113 m) above sea level, about 755 feet (230 m) above the average surface of the lake.
Lava lakes are large volumes of molten lava, usually basaltic, contained in a volcanic vent, crater, or broad depression. The term is used to describe both lava lakes that are wholly or partly molten and those that are solidified.
The Flourmill Volcanoes, also known as The Flourmills, are a small volcano range near the west boundary of Wells Gray Provincial Park in east-central British Columbia, Canada. Located north of Mahood Lake and west of the Clearwater River, they form part of the Wells Gray-Clearwater volcanic field.
Brennisteinsfjöll is a minor volcanic system, with crater rows and small shield volcanoes on the Reykjanes peninsula in Iceland.
Mount Iwate is a stratovolcano complex in the Ōu Mountains of western Iwate Prefecture, in the Tōhoku region of northern Honshū, Japan. With an elevation of 2,038 metres (6,686 ft), it is the highest in Iwate Prefecture. It is included as one of the 100 famous mountains in Japan, a book composed in 1964 by mountaineer and author Kyūya Fukada. The mountain is on the borders of the municipalities of Hachimantai, Takizawa, and Shizukuishi, west of the prefectural capital of Morioka. Much of the mountain is within the borders of the Towada-Hachimantai National Park. The mountain is also referred to as the "Nanbu Fuji" for its resemblance to Mount Fuji.
