JLKR+3.3

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Vocabulary

 * shield volcano-** when lava flows, it make a sloping mountain
 * cinder cone-** a cinder cone is a steep, cone-shaped hill or it could be a mountain
 * Composite Volcanoes-** tall mountains shaped like cones and are covered with layers of lava alternate with layers of ashes
 * caldera-** a huge hole left by a volcanic mountain that collapsed
 * volcanic neck-** when magma hardens in the volcano's pipe
 * dike-** when the magma forces itself across the rocks layer it hardens
 * sill-** when the magma goes between layers of hard rock
 * batholith-** a mass of rock that forms when a large body of magma in the crust cools

Outline
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Landforms From Lava and Ash

 * shield volcanoes
 * in some places in the Earth's surface, thin layers of lava pour out of a vent and harden on top of previous layers
 * the lava gradually builds a wide, gently sloped mountain
 * cinder cone volcanoes
 * a steep, cone shaped hill or mountain
 * if a volcano's lava is thick and stiff, it may produce ash, cinders, and bombs
 * these materials pile up around the vent in a steep, cone-shaped pile
 * composite volcanoes
 * tall, cone-shaped mountains which layers of lava alternate with layers of ash
 * lava plateaus
 * some eruptions of lava form high, level areas called plateaus
 * lava is thin and runny, so it can travel far before cooling
 * after millions of years, the layers of lava can form high plateaus
 * calderas
 * enormous eruptions could empty the volcano
 * mountain becomes a hollow shell
 * mountain caves in and is filled with remains of the volcano, as well as some lava and ash

Soils from Lava and Ash

 * the soils made from the lava is extremely fertile, so people settle near volcanoes

Landforms from Magma

 * volcanic necks, dikes, and sills
 * a volcanic neck forms when magma hardens in a volcano's pipe
 * magma that forces itself across rock layers hardens into a dike
 * when magma squeezes between layers of rock, it forms a sill
 * batholiths
 * a batholith is a mass of rock formed when a large body of magma cools inside the crust
 * dome mountains
 * forms when rising magma is blocked by horizontal layers of rock
 * the magma forces the layers of rock to bend upward into a dome shape