Long Valley Caldera is a depression in eastern California that is adjacent to Mammoth Mountain. The valley is one of the Earth's largest calderas, measuring about 20 mi (32 km) long (east-west), 11 mi (18 km) wide (north-south), and up to 3,000 ft (910 m) deep.
Crater Lake is a volcanic crater lake in south-central Oregon in the Western United States. It is the main feature of Crater Lake National Park and is famous for its deep blue color and water clarity. The lake partly fills a 2,148-foot-deep (655 m) caldera that was formed around 7,700 years ago by the collapse of the volcano Mount Mazama. No rivers flow into or out of the lake; the evaporation is compensated for by rain and snowfall at a rate such that the total amount of water is replaced every 250 years. With a depth of 1,949 feet (594 m), the lake is the deepest in the United States. In the world, it ranks tenth for maximum depth, as well as third for mean (average) depth.
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.
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.
Ngorongoro Conservation Area is a protected area and a UNESCO World Heritage Site located in Ngorongoro District, 180 km (110 mi) west of Arusha City in Arusha Region, within the Crater Highlands geological area of northeastern Tanzania. The area is named after Ngorongoro Crater, a large volcanic caldera within the area. The Ngorongoro Conservation Area Authority administers the conservation area, an arm of the Tanzanian government, and its boundaries follow the boundary of the Ngorongoro District in Arusha Region. The western portion of the park abuts the Serengeti National Park, and the area comprising the two parks and Kenya's Maasai Mara game reserve is home to Great Migration, a massive annual migration of millions of wildebeest, zebras, gazelles, and other animals. The conservation area also contains Olduvai Gorge, one of the most important paleoanthropological sites in the world.
A volcanic crater is an approximately circular depression in the ground caused by volcanic activity. It is typically a bowl-shaped feature containing one or more vents. During volcanic eruptions, molten magma and volcanic gases rise from an underground magma chamber, through a conduit, until they reach the crater's vent, from where the gases escape into the atmosphere and the magma is erupted as lava. A volcanic crater can be of large dimensions, and sometimes of great depth. During certain types of explosive eruptions, a volcano's magma chamber may empty enough for an area above it to subside, forming a type of larger depression known as a caldera.
An active volcano is a volcano that has erupted during the Holocene, is currently erupting, or has the potential to erupt in the future. A volcano that is not currently erupting but could erupt in the future is known as a dormant volcano. Volcanoes that will not erupt again are known as extinct volcanoes.
The Ijen volcano complex is a group of composite volcanoes located on the border between Banyuwangi Regency and Bondowoso Regency of East Java, Indonesia. It is known for its blue fire, acidic crater lake, and labour-intensive sulfur mining.
Arusha Region is one of Tanzania's 31 administrative regions and is located in the northeast of the country. The region's capital and largest city is the city of Arusha. The region is bordered by Kajiado County and Narok County in Kenya to the north, the Kilimanjaro Region to the east, the Manyara and Singida Regions to the south, and the Mara and Simiyu regions to the west. Arusha Region is home to Ngorongoro Conservation Area, a UNESCO World Heritage Site. The region is comparable in size to the combined land and water areas of the state of Maryland in the United States.
The Crater Highlands or Ngorongoro Volcanic Highlands are a geological region along the East African Rift in the Arusha Region and parts of northern Manyara Region in north Tanzania. The Crater Highlands are made up of several large volcanic complexes, including the 2.4-2.2 Ma Lemagarut and 2.25-2.0 Ma Ngorongoro basalt-trachybasalt-trachyandesite volcanoes and the 1.6-1.5 Ma Oldeani basalt-trachyandesite volcano.
Quilotoa is a water-filled crater lake and the most western volcano in the Ecuadorian Andes. The 3-kilometre (2 mi)-wide caldera was formed by the collapse of this dacite volcano following a catastrophic VEI-6 eruption about 800 years ago, which produced pyroclastic flows and lahars that reached the Pacific Ocean, and spread an airborne deposit of volcanic ash throughout the northern Andes. This last eruption followed a dormancy period of 14,000 years and is known as the 1280 Plinian eruption. The fourth eruptive phase was phreatomagmatic, indicating that a Crater lake was already present at that time. The caldera has since accumulated a 250-metre-deep (820 ft) crater lake, which has a greenish color as a result of dissolved minerals. Fumaroles are found on the lake floor and hot springs occur on the eastern flank of the volcano.
Blue Lake Crater is a maar, or a broad, low-relief volcanic crater, in the U.S. state of Oregon. Located in Jefferson County, it consists of three overlapping craters, which hold Blue Lake. The drainage basin for Blue Lake has very steep, forested slopes and is mostly part of the explosion crater left by the volcano's eruption. The volcano lies within the Metolius River basin, which supports a wide array of plant life, large and small mammals, and more than 80 bird species. A 2009 Oregon law designated the Metolius River basin as an area of critical concern, preventing large-scale development and protecting wildlife.
Halemaʻumaʻu is a pit crater within the much larger Kīlauea Caldera at the summit of Kīlauea volcano on island of Hawaiʻi. The roughly circular crater was 770 meters (2,530 ft) x 900 m (2,950 ft) before collapses that roughly doubled the size of the crater after May 3, 2018. Following the collapses of 2018, the bottom of Halemaʻumaʻu was roughly 600 m (2,000 ft) below the caldera floor. Halemaʻumaʻu is home to Pele, goddess of fire and volcanoes, according to the traditions of Hawaiian religion. Halemaʻumaʻu means "house of the ʻāmaʻu fern".
Ceraunius Tholus is a volcano on Mars located in the Tharsis quadrangle at 24.25° north latitude and 262.75° east longitude, part of the Uranius group of volcanoes. It is 130 kilometres (81 mi) across, approximately 8,500 metres (27,887 ft) high and is named after a classical albedo feature name.
The Gregory Rift is the eastern branch of the East African Rift fracture system. The rift is being caused by the separation of the Somali plate from the Nubian plate, driven by a thermal plume. Although the term is sometimes used in the narrow sense of the Kenyan Rift, the larger definition of the Gregory Rift is the set of faults and grabens extending southward from the Gulf of Aden through Ethiopia and Kenya into Northern Tanzania, passing over the local uplifts of the Ethiopian and Kenyan domes. Ancient fossils of early hominins, the ancestors of humans, have been found in the southern part of the Gregory Rift.
Satonda is a volcanic island off the northern coast of Sumbawa, in West Nusa Tenggara province of Indonesia; It main feature is a lake that has helped gain some insight in the formation of organisms.
A volcanic crater lake is a lake in a crater that was formed by explosive activity or a collapse during a volcanic eruption.
The Olmoti Crater is located at an elevation of 3,088 meters. Olmoti, which means "Cooking Pot" in Maasai, is an extinct volcano. The crater is located in Nainokanoka ward of Ngorongoro District in Arusha Region of Tanzania. Olmoti's highest peak is 3,080m, and the crater is approximately 6.5km in diameter.
Saidman volcano, also known as Sadiman or Satiman, is 2,879-meter-high stratovolcano located in Ngorongoro District of Arusha Region in Tanzania. The volcano is located in the geographic area known as the Crater Highlands and is a volcano that last erupted in the Pleistocene. The age of Sadiman volcano is unknown, with one source claiming a Pleistocene age and another claiming a K-Ar age of 4.5 million. Sadiman lava clasts have been discovered in layers dating back 1.7 to 2.0 million years. This volcano is part of the Serengeti-Ngorongoro UNESCO Biosphere Reserve in partnership with the Ngorongoro Conservation Area.
Kamoamoa is a set of volcanic fissures born on March 5, 2011, on the flanks of Kīlauea, Hawaii, US. Their opening between Puʻu ʻŌʻō to the east and Nāpau to the west follows a sudden drop in the level of lava lakes in the Puʻu ʻŌʻō and Halemaʻumaʻu craters, as well as an increase in nearby seismic activity, particularly tremors. Lava erupted for five days, forming a flow that advanced by around two kilometers. Following the eruption, a fire broke out in the forest.
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