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A cinder cone (or scoria cone [1]) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent. [2] [3] The pyroclastic fragments are formed by explosive eruptions or lava fountains from a single, typically cylindrical, vent.
Strombolian eruptions are a type of volcanic eruption named after the volcano Stromboli, which has been erupting nearly continuously for centuries. [13] Strombolian eruptions are driven by the bursting of gas bubbles within the magma. These gas bubbles within the magma accumulate and coalesce into large bubbles, called gas slugs.
Ultra-Plinian eruptions are the largest of all volcanic eruptions are more intense, have a higher eruption rate than Plinian ones, form higher eruption columns and may form large calderas. These eruptions produce rhyolitic lava, tephra, pumice and thick pyroclastic flows that cover vast areas and may produce widespread ash-fall deposits.
A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers of hardened lava and tephra. [1] Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and explosive eruptions. [2] Some have collapsed summit craters called calderas. [3]
Sector collapse can result from internal volcanic processes. Volcanic eruption can damage originally stable magma chambers, causing a portion of the volcano to collapse. [1] While eruption is one cause, sector collapse can occur without any eruption. Magmatic intrusions can also lead to sector collapse. Dikes fracture and deform rock, leaving ...
An eruption column or eruption plume is a cloud of super-heated ash and tephra suspended in gases emitted during an explosive volcanic eruption. The volcanic materials form a vertical column or plume that may rise many kilometers into the air above the vent of the volcano. In the most explosive eruptions, the eruption column may rise over 40 km ...
A.D. 79: Mount Vesuvius, Italy. Mount Vesuvius has erupted eight times in the last 17,000 years, most recently in 1944, but the big one was in A.D. 17. One of the most violent eruptions in history ...
A volcanic dam is a type of natural dam ... internal structure, ... The lava may flow during numerous successive or repetitive eruptions and may emanate from single ...