Question

Describe one type of volcanic formation.

Answer 1

Supervolcanoes

A supervolcano is a large volcano that usually has a large caldera and can potentially produce devastation on an enormous, sometimes continental, scale. Such eruptions would be able to cause severe cooling of global temperatures for many years afterwards because of the huge volumes of sulfur and ash erupted. They are the most dangerous type of volcano. Examples include Yellowstone Caldera in Yellowstone National Park and Valles Caldera in New Mexico (both western United States), Lake Taupo in New Zealand, Lake Toba in Sumatra, Indonesia and Ngorogoro Crater in Tanzania, Krakatoa near Java and Sumatra, Indonesia. Supervolcanoes are hard to identify centuries later, given the enormous areas they cover. Large igneous provinces are also considered supervolcanoes because of the vast amount of basalt lava erupted, but are non-explosive

Answer 2

Volcanoes form when hot material from below rises and leaks into the crust. This hot material, called magma, comes either from a melt of subducted crustal material, and which is light and buoyant after melting, or it may come from deeper in the interior of a planet and is light and buoyant because it is *very* hot.

Magma, rising from lower reaches, gathers in a reservoir, in a weak portion of the overlying rock called the magma chamber. Eventually, but not always, the magma erupts onto the surface. Strong earthquakes accompany rising magma, and the volcanic cone may swell in appearance, just before an eruption, as illustrated in this picture. White arrows in the picture show the volcano getting bigger as magma rises inside. Scientist often monitor the changing shape of a volcano, especially prior to an eruption. The different reasons why a volcano forms are

via plumes or hot spots in the lithosphere
as a result of subduction of the nearby lithosphere

Answer 3

Shield Volcanoes
Shield volcanoes can grow to be very big. In fact, the oldest continental regions of Earth may be the remains of ancient shield volcanoes.

Unlike the composite volcanoes which are tall and thin, shield volcanoes are tall and broad, with flat, rounded shapes. The Hawaiian volcanoes exemplify the common type of shield volcano. They are built by countless outpourings of lava that advance great distances from a central summit vent or group of vents. The outpourings of lava are typically not accompanied by pyroclastic material, which make the shield volcanoes relatively safe, as shown in this picture of scientists monitoring the eruption.

Mauna Loa, the largest of the shield volcanoes, is 13,677 feet above sea level, which means it rises over 28,000 feet above the deep ocean floor, and would be the worlds tallest mountain if much of it were not underwater.

Famous shield volcanoes include Mauna Loa, Kilauea, (two of the world's most active volcanoes), andOlympus Mons of Mars.