The Yellowstone Caldera, located in Yellowstone National Park in the U.S. state of Wyoming, is the result of the Yellowstone Supervolcano. This enormous volcano complex last erupted about 640,000 years ago. The Yellowstone Caldera is more than 72 kilometers (45 miles) long.
Composite volcanoes, sometimes known as stratovolcanoes, are steep-sided cones formed from layers of ash and acidic lava flows. Most composite volcanoes contain complex internal networks of lava flows which contain intrusive (below ground) igneous features such as sills and dykes. The eruptions from these volcanoes may be a pyroclastic flow rather than a flow of lava.
Template:Simp Vulcanicity (also known as volcanic activity or igneous activity) is one of the endogenetic processes. Magma under the crust is under very great pressure. When folding and faulting occur, cracks or fractures which are lines of weakness are created.
Basic lava: this is a form of fluid poor in silica content flows for a very distance before it solidifies, it builds up gently sloping cones, lava plateau and plains. Pyroclasts (Heated lava): when lava is heated, it breaks down into small fragments or pieces (pyroclasts) ,which usually falls to the ground and form layers of Ash/cinder.
Phreatomagmatic eruptions are a type of explosive eruption that results from the magma erupting through water. The second phase of the Ejyafjallajökull eruption in 2010 was phreatomagmatic as a result of magma erupting under the ice. Some submarine volcanoes are phreatomagmatic, if the magma is gas-rich. For example Surtsey in Iceland.
Shield volcano/basaltic lava volcano/basic lava cone - A shield volcano is a wide volcano with shal-lowly-sloping sides. A shield volcano have a broad profile is built up over time by flow after flow of relatively fluid basaltic lava issuing from vents or fissures on the surface of the volcano. Many of the largest volcanoes on Earth are shield volcanoes.
•Volcanoes of explosive type or central eruption type are associated with the accumulated volcanic materials in the form of cones which are called as volcanic cone. •There is a vent or opening ,of circular or nearly circular shape, almost in the centre of the summital part of the cone.
Plinian eruptions or Vesuvian eruptions are volcanic eruptions marked by their similarity to the eruption of Mount Vesuvius in 79 AD, which destroyed the ancient Roman cities of Herculaneum and Pompeii. The eruption was described in a letter written by Pliny the Younger, after the death of his uncle Pliny the Elder.
Vulcanian eruption. The term Vulcanian was first used by Giuseppe Mercalli, witnessing the 1888-1890 eruptions on the island of Vulcano. His description of the eruption style is now used all over the world for eruptions characterised by a dense cloud of ash-laden gas exploding from the crater and rising high above the peak.