1. Rocks Adapted from: Dr. Michael J. Passow

2. Sedimentary Rocks Consist mainly of weathered rock debris which have become compacted and cemented Cover about ¾ of Earth’s surface http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Sedrocks/Sedrocks6.html

3. Sediment Sizes Gritty in your teeth

4. Clastic texture - made of cemented (lithified) sediments, classified by their grain sizes Ex. Shale – the most common sedimentary rock http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Sedrocks/Sedrocks9.html

5. Chemical sedimentary rocks form by chemical precipitation (evaporation of water) Ex. - Limestone is made from calcite, chert from quartz, and rock salt is halite. http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Sedrocks/Sedrocks10.html

6. Biochemical/Organic sedimentary rocks – come from the remains of organic matter Lignite, Bituminous, Anthracite coal results from the greatest pressure and releases the most energy when burned. Coquina forms from sea shells Fossiliferous limestone formed from shell fragments http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Sedrocks/Sedrocks11.html

7. IGNEOUS ROCKS Form from crystallization of magma EXTRUSIVE – formed from lava –Fine-grained (small) crystals –Glassy (no crystals) INTRUSIVE - formed from magma –Coarse-grained (large) crystals

8. Aphanitic Texture - Crystals are uniformly fine- grained - Individual crystals invisible to the unaided eye - Magma cooled rapidly Ex. - Basalt

9. Porphyritic Texture - Large crystals (phenocrysts) are surrounded by an aphanitic matrix (groundmass) - 2 rates of cooling Ex. – Diorite porphyry

10. Vesicular Texture - Vesicles are holes produced by gases escaping from lava as it solidifies - Cooled rapidly Ex. - Scoria

11. Glassy Texture - Very rapid cooling - Volcanic glass Ex. - Obsidian

12. Phaneritic Texture - Large crystals - Cooled slowly, underground - Individual minerals are evident Ex. - Diorite

13. Granite Light-colored, coarse- grained, no pattern Mostly quartz, feldspar, mica, and hornblende Often used for buildings and monuments http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Rocks/Rocks10.html

14. Basalt Dark-colored, fine-grained, extrusive Formed where lava erupted onto surface Most widespread igneous rocks http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Slideshow/Igrocks/Igrock2.html

15. Gabbro Dark-colored, coarse- grained intrusive Similar composition to basalt—plagioclase feldspar with some pyroxene and olivine http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Slideshow/Igrocks/Igrock8.html

16. Obsidian Natural volcanic glass Forms when lava cools very quickly Usually dark, but small pieces may be clear Fractures along curved (conchoidal) surface Used as spear and arrow points, knives http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Slideshow/Igrocks/Igrock7.html

17. Pumice and other igneous rocks Light colored, frothy (many air spaces) Same minerals as in granite, but finer in grain size For more about igneous rocks: http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Igrocks/Igro cks1.html http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Igrocks/Igro cks1.html

18. Metamorphic Rocks Formed by heat and pressure changing existing rocks REGIONAL METAMORPHISM affects a large area and results from plate tectonics CONTACT METAMORPHISM affects rocks on a local scale, such as “baking” sedimentary rocks next to magma or lava http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Metrocks/Metrocks1.html

19. “Foliated” texture show layering or banding http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Metrocks/Metrocks5.html

20. Non-foliated texture rocks include marble, which comes from limestone, and quartzite, which comes from sandstone http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Metrocks/Metrocks12.html

21. http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Rocks/Rocks8.html

22. Rock Cycle

23. http://www.volcanoworld.org/vwdocs/vwlessons/lessons/Metrocks/Metrocks2.html