Volcanoes: The Earth’s Geographical Sculptors
By Amita Vadlamudi A volcano is a crack or fissure in the crust of the Earth or another celestial body through which lava, volcanic ash and gases escape. Volcanoes are a display of the Earth’s magnitude and power. They can be fascinating to watch, despite holding immense destructive power. Volcanoes may be active, dormant, or extinct. What Causes Volcanic Eruption? These conical structures are a composition of eruptive elements. Volcanoes ignite when magma rises to the Earth’s surface as ‘lava’. This is usually spurred by the activity of the tectonic plates. When tectonic plates converge, pieces of the Earth’s crust nestle deep into the interior. When the crust melts due to high heat and pressure, it rises up as magma. When tectonic plates diverge, magma rises up to fill these gaps, usually resulting in the formation of underwater volcanoes. Types of Volcanoes Volcanoes are generally categorized into four groups. Cinder Cones
Cinder Cones, also known as Scoria Cones, are heralded the most common category of volcanoes. With a height of merely 300 feet, they are also the smallest. They comprise tiny fragments of hardened lava usually from a single eruption. Shield Volcanoes Shield Volcanoes exhibit a large base with a width 20 times its height. The low viscosity of lava lends these volcanoes its broad shape. The eruptions of these volcanoes are usually not explosive and mimic the overflow of liquid around the boundaries of a container. Composite Volcanoes Also known as Stratovolcanoes, Composite Volcanoes result in highly explosive eruptions. Some of the Earth’s grandest mountains are Composite Volcanoes. The most violent type, they are likely to cause massive destruction. Lava Domes When lava is too viscous to flow to a distance, it heaps up around the vent, resulting in Lava Domes. They usually form on the flanks of Composite Volcanoes. Destructive Powers Research reveals volcanic eruptions spew an average of $1 billion yearly on property damage. They can cause floods, earthquakes, and rock falls, simultaneously destroying everything
in its path. The amalgamation of hot gas and ash can cause suffocation among humans and animals. The Permian Mass Extinction is remembered as one of the deadliest eruptions in history, wiping out massive hoards of marine life and land dwellers. Distinct Landforms Apart from the renowned volcanoes, Mount Fuji and Kilimanjaro, Volcanic eruptions have gifted the Earth with an array of distinctive landforms like calderas, domes, plateaus, and craters, some of which serve as major tourist attractions. About the Author: Amita Vadlamudi, a retired computer professional is an avid reader and blogger. Following are two of Amita Vadlamudi’s other blog sites. Amitavadlamudi.com Amitavadlamudi.org