Geography 2152F/G Lecture Notes - Lecture 8: Maple Syrup, Cinder Cone, Pyroclastic Rock
6 Dec 2018
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Document Summary
Volcanoes: most volcanoes are located near plate boundaries, nearly 2/3 of all volcanoes are found on the ring of fire" surrounding the pacific ocean, subduction zones and mid-ocean ridges allow molten rock to reach the surface. It is found deep within the crust and upper mantle: lava, essentially, lava is magma on the earth"s surface. Types of volcanoes: volcanoes are classified into 4 different types, the classification is based on their shape, appearance, and style of eruptions, types of volcanoes, shield, composite, volcanic dome, cinder cone. If compacted together, these deposits are called pyroclastic rock: these volcanoes are common in hawaii, iceland and around the indian ocean, notice it is not near the pacific ocean. St. helens (both in washington state) are the most well-known composite volcanoes in north america. Volcanic domes: these volcanoes contain highly viscous rhyolite magma, they are steep-sided mounts that form around vents.
