VolcanoesMiss 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 EruptionsThere 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.

Non-explosive eruption

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.

Explosive Eruption

Volcano Video

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)