Presentation on theme: "My PowerPoint on Volcanoes'"— Presentation transcript:
1 My PowerPoint on Volcanoes' Written By Ethan Cassar
2 What is a Volcano?.A volcano is a opening in the earths crust through which molten lava, ash and gases are ejected from. There are 3 types of volcano formsShielded volcano, Strato volcano and Cinder-Cone volcano-Shielded volcano=Hawaiian eruptions, the calmest of them all, these volcanoes have a steady flow of lava that helps to build up and make these volcanoes so massiveStrato volcano= Highly explosive eruptions, these volcanoes are the most dangerous and are associated with causing massive destruction.Cinder-Cone volcano=Associated with a strombolian eruption, short-lived, explosive outbursts of pasty lava that is ejected into the air.
3 How long have volcanoes been on our earth? The oldest volcano on earth is approximately 350,000 years old but volcanoes have been around ever since the earth was formed. When the earth was formed it was a rocky, hot planet and everywhere had volcanos on it.But when the moon was formed by a colliding planet it destroyed earths volcanos and formed mountains from the destroyed rubble.
4 What are the parts of a volcano? .Crater: The top of the volcano where lava, ashes and gases eject from. Flank: The side or rear of a volcano where magma flows through. Throat: A throat of a volcano is where the width of the hole of the conduit pipe increases. The throat of a volcano gives the magma more space to flow out/gush out of the mountain as lava Conduit pipe: The conduit in a volcano is the 'vent' or 'pipe' through which lava passes through. Summit: The highest point of a volcano. Vent: An opening in Earth's surface through which volcanic materials escape. Parasitic Cone: A small cone-shaped volcano formed by an accumulation of volcanic debris. Sill: A flat piece of rock formed when magma hardens in a crack in a volcano. Ash: Fragments of lava or rock smaller than 2 mm in size that are blasted into the air by volcanic explosions. Credit to Resource Woodland for information
5 How is a volcano formed?Deep inside Earth, between the molten iron core and the thin crust at the surface, there is a solid body of rock called the mantle. When rock from the mantle melts, moves to the surface through the crust, and releases pent-up gases, volcanoes erupt Extremely high temperature and pressure cause the rock to melt and become liquid rock or magma. When a large body of magma has formed, it rises through the denser rock layers toward Earth's surface. Magma that has reached the surface is called lava
6 When was volcanic activity discovered? Its volcanic activity was discovered in 1979 by Voyager 1 imaging scientist. Observations of Io by passing spacecraft (the Voyagers, Galileo, Cassini, and New horizons) and Earth-based astronomers have revealed more than 150 active volcanoes. Up to 400 such volcanoes are predicted to exist based on these observations
7 Any myths leading to the volcano? . The great eruption at Santorini in 1500 BC may be the origin of the Atlantis myth. Pele, Hawaii's goddess of fire, can take many forms. she is the lava that pours across the ground. She can also be a white dog, and old woman, or a beautiful young woman.. A man-eating demon named Tamaohoi once lived on the flank of Mount Tarawera, in New Zealand. He was imprisoned on the mountain by Ngatoro. Tamaohoi slept for many centuries. Under the influence of the white man, the morals of the local people declined until there was a call for Tamaohoi to return and punish the sinners.Tamaohoi exploded from the mountain and killed many people in the village of Te Ariki.
8 Which people study volcanoes? Volcanologists study volcanoes they study the actual process and deposit of a volcanic eruption but it takes time to do this they have to collect all data of it, mapping of the distribution of rocks that make up to a volcano, as well as chemical and dating analyses.
9 How is magma formed?Magma is a mixture of molten rock, which is formed beneath the earths surface, the magma its self is not made by the volcano magma is constant beneath the earth everywhere as parts of its layers, it helps shift the plates.
10 What is the tallest active volcano on earth? The Mauna loa volcano in Hawaii is the tallest active volcano on earth, it is 13,677 feet above sea level. That makes it taller than MT, Everest!!. Its last eruption was in 1984 and it emerged out of sea 400,000 years ago!
11 What to do during a volcanic eruption Be aware of mudflows. The danger from a mudflow increases near stream channels and with prolonged heavy rains. Mudflows can move faster than you can walk or run.Avoid river valleys and low-lying areas.Remember to help your neighbours who may require special assistance – infants, elderly people, and people with disabilities. Protection from Falling Ash Listen to a battery-powered radio or television for the latest emergency information.These are the few of the many things you need to do during a eruption.
12 Thanks for your attention!!!! I appreciate all of your listening and consideration of my powerpoint!