Volcanoes

Volcanoes

Volcanoes are natural phenomena which are on the Earth’s surface through which molten rock and gases escape from below the surface (Tarbuck, 139). These volcanoes are very interesting to observe and to study because of their amazing occurrences and majestic lava eruptions. Volcanoes have been studied ever since the beginning of mankind and the word “volcano” is thought to be derived from Vulcano, a volcanic island in the Aeolian Islands of Italy whose name in turn originates from Vulcan, the name of a god of fire in Roman mythology. Consisting of several types, volcanoes can extrude several forms of magma and can also release multiple gases. These extruded materials can affect the Earth’s structure and atmosphere.

There are three types of volcanoes existent on the Earth. The most common type of volcano is a cinder cone. A cinder volcano is built from ejected lava fragments that take on the appearance of cinders as they begin to harden while in flight. (Tarbuck, 152) The structure of this volcano is determined by the shape and slope that the pyroclastic material forms as it hardens. Usually, these volcanoes are symmetrical in shape, with elongated flanks and can have large craters caused by volcanic activity (Tarbuck, 153). Examples of cinder cone volcanoes are Holocene in Utah and Capulin in New Mexico. In addition to the cinder cone volcano, the shield volcano is also another type of volcano that is common on the Earth. The shield volcano is produced by the accumulation of fluid basaltic lava and exhibits the shape of a broad slightly domed structure (Pillai). Younger aged shields tend to emit fluid lava from a central vent and have sides that vary from 1 to 5 degrees (Pillai). On the other hand, older shield volcano...

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