PPT-Vile volcanoes

T his is a map of Pompeiis famous volcano called Mount Vesuvius How many volcanoes are there in the world There are around 1510 active volcanoes in the world We currently know of 80 or more which are under the oceans . Gwen . Nytes. Composition. The magma in this type of volcano is made of basaltic-andesitic materials. The magma has an intermediate viscosity, so . it’s mildly explosive. It also consists of a lot of gases, so when the lava cools and hardens in the air, gas bubbles get trapped inside. The particles fall back down as cinders, and pile around the vent.. 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!. Basaltic Lava – low silica content, low viscosity, low gas content. Hot spots – magma moves up from lower mantle and plates move over it . Ex. Hawaii. (note: see video on favorites). Shield Volcanoes. Turn over this gory page to find out about the Victorians with the boring bit picked out…. introduction. Take a look at this AMAZING description .Find out how you would of been treated if you was a Victorian school child . Queen Victoria ruled from 1837 to 1901.. By Robbie Barker, Maximilian Bryson, and Brendan . P. etrili. What is a volcano. A volcano is an opening in the Earth’s surface through which magma rises.. Formation of volcanoes. 1.Most volcanoes occur at colliding boundaries.. What is a Volcano. Volcano: a weak spot in the crust where molten rock (magma) comes to the surface. Most volcanoes are located around subduction zones and hot spots. Over 75% of worlds volcanoes are found . Warm Up. Why do you think magma rises? Consider an ice cube floating at the top of a glass of water. Objective:. SWBAT. Describe at least two of the three types of volcanoes and how they form. Agenda:. 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”.. VOCABULARY WORDS. ENGLISH 8. 1. Disreputable -- . Disgraceful, dishonorable, or infamous . . Mr. Hyde was considered to be a . disreputable. man due to the many horrible acts he committed in London. . 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. Compare the features of volcanoes.. Describe the stages in volcano formation.. What are Volcanoes?. Volcanoes are vents through which molten rock and gas escape from a . magma chamber.. Volcanoes can differ. Vocabulary. Unit 4 . 1. Precocious . adj.. Displaying or characterized by unusually early development or maturity, especially in . intelligence. Blind children, it has often been noted, tend to be . precocious. 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. .