Volcanoes
From GeoClasses
Contents |
What is a volcano?!
A volcano is a geological landform, usually a mountain, where magma (rock of the earth's interior made molten or liquid by high pressure and temperature) erupts through the surface of the planet. This phenomenon tends to occur near the boundaries of continental plates, and hotspots.
What are the different types of volcanoes?!
The three major volcanic types are: shield volcanoes, cinder cones, and composite cones. The types of volcanoes are distinguished by the material they eject, for it determines the shape of the mountain. For example, a shield volcano produces lava of low viscousity so the lava flow is less inhibited down the sides which causes a very shallow, gentle slope.
Shield volcanoes are produced by the accumulation of fluid basaltic lavas and exhibited in the shape of a broad slightly domes structure that resembles a warrior's shield.
Cinder cone volcanoes (also called scoria cones) are built from ejected lava fragments that take on the appearance of cinders or clinkers as they begin to harden while in flight.
Composite cones or stratovolcanoes, are Earth's most picturesque, yet potentially dangerous volcanoes. These volcanoes are formed of both lava flows and pyroclastic (volcanic rock ejected during an eruption, including ash, bombs, and blocks) material.
Some exciting examples of volcanoes:
Shield volcanoes: Kilauea erupting, and the world's largest volcano, Mauna Loa -Hawaii.
Cinder cone volcano: in Veniaminoff, Alaska bursting lava fragments.
Composite volcano: Picturesque but deadly Mount St. Helens
Test Question
What are the three main types of volcanoes?
