The Physical Environment

                                                 Contents |Glossary | Atlas | Index |Blog|Podcasts| Earth Online | Updates

Igneous Rock


basalt_small.jpg (12544 bytes)
Click image to enlarge

Basalt is an example of a fine grained,
extrusive igneous rock

devils_tower_DDS21_TDE0012_small.jpg (18240 bytes)
Click image to enlarge

Devil's Tower, WY. is an igneous body
(volcanic neck) exposed by erosion

Photo credit: USGS Digital Data Series DDS-21

Igneous rocks form from the cooling of magma or lava (magma extruded on to the surface). If molten rock cools slowly beneath the surface of the earth it forms coarse grained rocks like granite. Rapid cooling above the surface produces fine-grained rocks like basalt.

 
 

 ~ Previous ~

| A | B | C | D | E | F| G | H | I | J | K | L | M |

| N | O | P | Q | R | S | T | U | V | W | X | Y | Z |

Contents |  News | WebActive | Glossary | Atlas | Index |  Earth Online | Top of page

About "The Physical Environment" | Who's Using TPE

Please contact Michael Ritter for inquiries, permissions, corrections or other feedback.

© 2003 - 2006 Michael Ritter (mritter@uwsp.edu)
Last Revised September 26, 2006