Volcanoes By: Cody and Jennifer

When a volcano erupts, it either has a lava flow or pyroclastic flow Magma that flows onto earth’s surface is called lava, and when it’s underground it is called magma

There are four types of lava o Blocky lava- cool, stiff lava that cannot travel far o Pahoehoe- flows slowly, forming glassy surface with rounded wrinkles o Aa- lava has a jagged surface o Pillow lava- forms when lava erupts underwater

Block lava Pillow lava pahoehoe Aa

There are three different types of volcanoes; shield volcano, cinder cone volcano, and composite volcano Shield volcano- built from layers of lava from repeated nonexplosive eruptions Cinder cone volcano- made entirely of pyroclastic material from explosive eruptions Composite volcano- formed by explosive eruptions of pyroclastic material followed by quieter outpourings of lava

Volcanoes

Vocabulary Section 1 Volcano – mountain that forms when magma is forced to earth’s surface Lava – magma that flows onto the earth’s surface Pyroclastic material – consists of rock fragments created created by explosive volcanic eruptions

Vocabulary Section 2 Shield volcano – built out of layers of lava Cinder cone volcano – made of pyroclastic material Composite volcano – formed by explosive eruptions of pyroclastic material followed by quieter outpourings of lava Crater – central vent in volcanoes is a funnel- shaped pit Caldera – magma chamber empties and it’s roof collapses

Vocabulary Section 3 Rift – when the tectonic plates separate, a deep crack forms between the plates Hot spots – places on the earth’s surface that are directly above columns of rising magma, which is also called mantle plumes

Summary So there are three different types of volcanoes which are shield volcano, cinder cone volcano, and composite volcano. Craters are funnel-shaped pits that form around the central vent of a volcano. Calderas are a large bowl-shaped depressions formed by a collapsed magma chamber.