Igneous Rocks 6 th Grade Science Mrs Pancake

Igneous Rocks 6 th Grade Science Mrs. Pancake Contact Teacher Summer 2003

How are they formed? Lava Magma

Lava Magma • Magma: molten material inside the earth’s surface. • Lava: molten material outside the earth’s surface.

Intrusive Rocks Gabbro Diorite Granite Peridotite

When magma underneath the surface cools, Intrusive Rocks are formed. They cool slowly, allowing visible crystals to form.

Texture Close up of Diorite Large, Visible Crystals Coarse-Grained Close up of Granite Coarse-grained texture can also be called phaneritic texture.

Extrusive Rocks

When the lava from a volcano cools and hardens, Extrusive rocks are formed. The lava cools too quickly for visible crystals to form.

Texture 1. Very rapid cooling a. No Crystals---Shiny---Glassy Close-up of Obsidian b. No Crystals---Holy---Vesicular rapid gas escaping

Texture 2. Quick Cooling Close-up of Basalt a. Small crystals---fine grained Close-up of Rhyolite

Credits Basalt image, Pumice image, Rhyolite image, Obsidian image: http: //volcano. und. nodak. edu/vwdocs/vwlessons/Igrocks 1. html Magma image: http: //www. iss. k 12. nc. us/schools/ems/falcons/Goldrick%20 Scie nce/Igneous%20 Rocks. htm : Granite image: http: //sln. fi. edu/fellows/payton/rocks/expert/granite. htm Volcano: http: //volcano. und. nodak. edu/vwdocs/vwlessons/Igrocks 3. html Lava image: http: //www. zero-kelvin. com/hi 02/000204. php

Igneous rock creation image: http: //www. geocities. com/Rain. Forest/Canopy/1080/ igneous_formation. htm Diorite image: http: //geology. csupomona. edu/alert/igneous/iddiorite. htm Gabbro image: http: //geology. csupomona. edu/alert/igneous/idgabbro. htm Peridotite image: http: //geology. csupomona. edu/alert/igneous/idperidotite. htm Magma image: http: //pubs. usgs. gov/gip/volc/types. html Phaneritic texture image: http: //geology. csupomona. edu/alert/igneous/texture. htm

Close-up of Rhyolite: http: //www. geolab. unc. edu/Petunia/Ig. Met. Atlas/volcanicmicro/rhyolite. X. html Close-up of Basalt: http: //www. geolab. unc. edu/Petunia/Ig. Met. Atlas/volcanicmicro/vesicles. X. html Close up of Obsidian: http: //www. geolab. unc. edu/Petunia/Ig. Met. Atlas/volcanicmicro/vitrophyre. X. html Close up of Diorite: http: //www. geolab. unc. edu/Petunia/Ig. Met. Atlas/plutonicmicro /sieve. X. html Close up of Granite: http: //www. geolab. unc. edu/Petunia/Ig. Met. Atlas/plutonicmicro /poikilitic 1. X. html