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Volcanoes. Miss Holdstein 6 th Grade Science. Standards Addressed. Students know evidence of plate tectonics is derived from the fit of the continents; the location of earthquakes, volcanoes, and midocean ridges; and the distribution of fossils, rock types, and ancient climatic zones.
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Volcanoes Miss Holdstein 6th Grade Science
Standards Addressed • Students know evidence of plate tectonics is derived from the fit of the continents; the location of earthquakes, volcanoes, and midocean ridges; and the distribution of fossils, rock types, and ancient climatic zones. • Students know earthquakes, volcanic eruptions, landslides, and floods change human and wildlife habitats.
Volcanic Eruptions There are two types of volcanic eruptions: • Non-explosive • Explosive
Non-explosive Eruptions • Most common type of volcanic eruption. • Produces lava flows, relatively calm outpourings of lava. • Many of the largest mountains on Earth have been formed as the result of lava flows from repeated non-explosive eruptions over hundreds of thousands of years.
Explosive Eruptions • Clouds of hot debris and gases shoot out from the volcano. • No lava flow, instead molten rock is blown into millions of pieces that harden in the air. • An explosive eruption can blast millions of tons of rock from a volcano, demolishing rock formations that took thousands of years to form.
References • Text- Holt Earth Science California edition • Photos & Video: • Explosive eruption (www.ime-usa.com/.../ guagua_eruption_lg.jpg ) • Non-explosive eruption (library.thinkquest.org/ J001393/volcanoes/3.htm) • Video (www.volcanolive.com)