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Mountain Metres Feet Location and Notes Ojos del Salado: 6,893: 22,615: Argentina/Chile – highest dormant volcano on Earth: Monte Pissis: 6,793: 22,287: Argentina Nevado Tres Cruces
The southwest peak has the highest elevation and is topped by a 200 m (656 ft) wide crater that contains a small lake. [9] The volcanic history of Mount Apo is poorly known but eruptions have produced andesitic-to-dacitic lava. A line of solfataras extend from the southeast flank at an elevation of 2,400 m (7,874 ft) to the summit.
A volcano needs a reservoir of molten magma (e.g. a magma chamber), a conduit to allow magma to rise through the crust, and a vent to allow the magma to escape above the surface as lava. The erupted volcanic material (lava and tephra) that is deposited around the vent is known as a volcanic edifice, typically a volcanic cone or mountain. [2] [22]
Twelve volcanoes in the arc are over 10,000 feet (3,000 m) in elevation, and the two highest, Mount Rainier and Mount Shasta, exceed 14,000 feet (4,300 m). By volume, the two largest Cascade volcanoes are the broad shields of Medicine Lake Volcano and Newberry Volcano, which are about 145 and 108 cubic miles (600 and 450 km 3) respectively.
There are more than 70 volcanic vents known as the Kunlun Volcanic Group in Tibet at higher elevations than Damavand's summit, the highest of which has a reported elevation of 5,808 m (19,055 ft) (35.5°N 80.2°E). Peaks in this volcanic group are not considered volcanic mountains but instead a type of pyroclastic cone. [6]
Volcanologists frequently visit volcanoes, especially active ones, to observe volcanic eruptions, collect eruptive products including tephra (such as ash or pumice), rock and lava samples. One major focus of enquiry is the prediction of eruptions; there is currently no accurate way to do this, but predicting or forecasting eruptions, like ...
Volcanoes are usually mountains (sometimes islands, lakes, plateaus, calderas, seamounts or lava domes) that are formed when magma (liquid rock) wells up from inside the Earth. There are also analogous formations away from the Earth. Many volcanoes are categorized both as volcanoes and other landforms, such as mountains (if qualified).
A’a lava has a rough, spiny surface made of clasts of lava called clinkers. [16] Block lava is another type of lava, with less jagged fragments than in a’a lava. [17] Pahoehoe lava is by far the most common lava type, both on Earth and probably the other terrestrial planets. It has a smooth surface, with mounds, hollows and folds. [3]