The inside of a volcano has one or more vents through which gas and lava flow during eruptions. Below the vent is the magma, which is the molten rock that flows upward due to the divergence or convergence of tectonic plates in the Earth's crust. The number of vents and shape of the buildup of magma inside the magma chamber depends upon the type of volcano.
Cinder cone volcanoes have single vents. Their bowl-shaped craters form from particles of cooling lava. Lava does not always flow from the tops, but the discharge of particles may cause lava fountains. Stratovolcanoes, or composite volcanoes, may have one or a cluster of vents. These volcanoes consist of cones formed from multiple layers of lava flows. Magma flows upward from a deep magma reservoir and flows out through breaks in the wall of the crater and cracks and fissures on the sides.
Shield volcanoes may have one or a group of vents through which lava flows. They usually have broad slopes spread out over a large area. The fluid lava flows not only through the vents but from rift zones that open on the flanks. Lava domes are formed by the accumulation of highly viscous lava within a vent chamber. These buildups can cause explosive eruptions or collapse to cause deadly pyroclastic currents of swift-flowing lava.Learn More
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-shaped mountains form, which are also called volcanoes.Full Answer >
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.Full Answer >
Various factors trigger a volcanic eruption. The three predominant factors are the magma's buoyancy, the pressure from the gases that separate in the magma and the merger of a new batch of magma with a chamber already filled with magma.Full Answer >
Volcanic eruptions mainly produce steam (H2 0 ), sulfur dioxide (SO 2 ) and carbon dioxide (CO 2 ). They do release other gases in lesser amounts, such as carbon monoxide (CO), helium (He), hydrogen (H 2 ), hydrogen chloride (HCL), hydrogen fluoride (HF) and hydrogen sulfide (H 2 S).Full Answer >