PPT-volcanoes

By Robbie Barker Maximilian Bryson and Brendan P etrili What is a volcano A volcano is an opening in the Earths surface through which magma rises Formation of volcanoes 1Most volcanoes occur at colliding boundaries. Chapter 5. Rigid Earth to Plate Tectonics. Learning Objectives. Know the different types of volcanoes and their associated features. Understand the relationship of the volcanoes to plate tectonics. Know what geographic regions are at risk from volcanoes. Yellowstone Park is not only spectacular but also unique. It is the result of three volcanic eruptions, the likes of which have never been seen in all of recorded history. The first eruption occurred 2 million years, followed by two more eruptions 1 million years and 600,000 years ago. Below Yellowstone Park there is a hot spot that is generating basaltic magma. At the time of each of their three eruptions, the magma chamber began to produce large volumes of basaltic magma. Because of its low viscosity, the basaltic magma quickly rose to the bottom of the granitic continental crust. However, because the density of basaltic magma (density about 3) is slightly higher than that of granite (density about 2.9) it could not force its way through the granite to the surface. Instead, it began to pool beneath the granitic crust. The amount of heat trapped within the molten basaltic magma was enough to melt the minerals making up the overlaying and surrounding granite, forming a growing mass of granitic magma. Granitic magma is highly viscous and extremely gas-charged. Although it rose only very slowly, the granitic magma advanced upwards by melting even more of its own overlying granitic rock. At some point, radial fractures began to form around the rising mass of granitic magma. These fractures allowed steam eruptions to vent gas. Shortly after, with the overlying granitic rock severely weakened by the fractures, the highly gas-charged granitic magma erupted. The land to a distance of 200 miles in all directions was decimated. Pyroclastic flows, the most destructive eruptive features known, swept across the countryside. Ash fell across the country from the eruption site to the Atlantic Ocean. Ash polluted the world’s atmosphere, blocked the energy of the Sun, and plunged the Northern Hemisphere into a frozen wasteland for years. Can such an eruption occur in the Yellowstone region again? All the evidence suggests that the magma chamber below Yellowstone Park is current rising. According to the director of the Yellowstone Volcanic Observatory, it is not a question of whether or not another super-eruption CAN happen; it’s a question of WHEN it will happen!. Target #16- I can summarize the conditions needed for magma to form. Despite the high temperature in the mantle, most of the layer remains solid due to extreme pressure. Magma: . liquid rock produced under Earth’s surface. Volcanism is mostly focused at plate margins. Pacific Ring of Fire. This map shows the margins of the Pacific tectonic plate and surrounding region. The red dots show the location of active volcanism. Notice how the majority of the volcanism is focused in lines along the plate boundaries? For this region is the area known as the “Pacific Ring of Fire”.. Earth Science Fall . 2012 . Vocabulary: . aa. – jagged chunks of lava formed by rapid cooling on the surface of the lava flow . Vocabulary:. Caldera- large basin-shaped depression formed when an explosion destroys the upper part of a volcanic cone or when the magma chamber below a volcano is emptied during an eruption. rd. graders. By Amy Zimmerman. what I hope my students learn…. What a volcano is.. Understand that there are 3 main types of volcanoes.. Understand the process of eruption. . Know all the different parts of a volcano.. Do Now: How many natural disasters can you name. ?. HW: Article . due Wednesday. Volcanoes are responsible for:. producing . most of the water . on . Earth. .. modifying . the . Earth’s atmosphere.. Volcanism is mostly focused at plate margins. Pacific Ring of Fire. This map shows the margins of the Pacific tectonic plate and surrounding region. The red dots show the location of active volcanism. Notice how the majority of the volcanism is focused in lines along the plate boundaries? For this region is the area known as the “Pacific Ring of Fire”.. Describe how the locations of volcanoes are related to plate tectonics.. Suggest why volcanoes are found at convergent and divergent plate boundaries.. Describe how . intraplate. volcanoes form.. Volcanic activity takes place primarily at . 9.1 – How & Where do Volcanoes Form?. One of the most dramatic activities associated with plate tectonics is the eruption of a volcano.. Volcano refers to both:. The . opening. in Earth’s crust through which molten rock, gases, and ash erupt.. Where are the major zones of volcanism?. What are the parts of a volcano?. How do volcanic landforms differ?. Copyright © McGraw-Hill Education. Volcanoes. Review. convergent. New. volcanism. hot spot. Volcanoes. Volcano:. mountain that forms in Earth’s crust when molten material (magma) reaches the surface. . Remember, . magma . is molten rock below ground; . lava. is molten rock at the surface. . What are volcanoes?. Does anyone know what a volcano is?. A volcano . is a landform (usually a mountain) where . liquid rock . erupts through the surface of the planet. .. The name "volcano" has its origin from the name of Vulcan, a god of fire in Roman mythology.. Structure of the Earth. What are the different layers of the Earth?. Structure of the Earth. Inner core. 6000. °C. Solid metal. Structure of the Earth. Outer core. 4500-6000. °C. Liquid metal. Structure of the Earth.