In this project we will explore how volcanoes affect the people who live near them; and how people effect the volcanoes. Along with describing the topic.
Before we go any further we must understand what a volcano is and what it does. The exact definition in the dictionary says it is a mountain with a hole through which lava, ashes, smoke, etc., are discharged. More specifically a volcano is a vent in the Earth from which molten rock (magma) and gas erupt. The molten rock that erupts from the volcano forms a hill or mountain around the vent. All the eruptions differ from one another. Gases from within the earth's interior mix with huge quantities of dust and ash and rise into the air as great dark clouds that can be seen from many kilometers away. Explosive eruptions are caused when lava in the vents hardens into rock. Steam and lava build up under the rocks. When the pressure of the steam and new lave becomes great, a violent explosion occurs.
In order to indicate the relative activity of volcanoes, scientists classify them as active, dominant, or extinct. An active volcano is one that erupts either continually or periodically. A volcano that has been known to erupt within modern times but is now inactive is classified as a dormant or sleeping volcano. A volcano not known to have erupted within modern history is classified as an extinct volcano. .
There are many different types of volcanoes, and each of them work in different ways. The form of a volcano is determined by the ingredients of the erupting magma. Their shapes are determined by the explosivity of the eruptions and the amount of water in the magma. .
Shield Volcanoes: are large forms with broad summit areas and low, sloping sides. This type is caused by slow, basaltic lava flows. An example of a shield volcano is the island of Hawaii.
Cinder Cones: are mounds that are formed by streaming gases that carry lava splotches and ribbons into the atmosphere to form lava fountains.