A volcano is a place where molten rock seeps or erupts from beneath the crust. Most volcanoes develop in the oceans, but some occur on land. When the molten rock, which is called lava, erupts with force, large, cone-shap... More »

A volcano forms when magma rises through weakened areas of the crust from a magma reservoir many miles deep within the earth, pushing itself up through a vent. This vent acts as a release valve for pressure building up b... More »

www.reference.com Science Earth Science Volcanoes

A volcano forms when a vent in the Earth's crust allows magma to well up from below. The magma fills a void underneath the surface, and when it builds up enough pressure, it bursts through to the surface. As the magma co... More »

A volcano occurs when molten rock wells up from the mantle to breach the Earth's crust. Most commonly, this occurs around the edges of tectonic plates. When two plates collide, one may slide underneath its neighbor, open... More »

A volcano that has recently erupted and may erupt again soon is categorized as an active volcano. Dormant and extinct are also categories of volcanoes. More »

www.reference.com Science Earth Science Volcanoes

According to the UCSB Geology Department, a volcanic eruption is defined as a volcanic event resulting in the emission of gases, lava, ash or other material from a volcano. These can manifest as a single eruptive pulse, ... More »

When a volcano erupts, magma from beneath the Earth is forced out of the volcano's mouth in the form of molten lava. Large amounts of gases and ash can also be released with the lava, depending on the type of eruption. More »

www.reference.com Science Earth Science Volcanoes