1 / 12

Understanding Igneous and Metamorphic Rocks: Characteristics and Classification

This lesson focuses on identifying rocks based on their physical characteristics, particularly igneous and metamorphic types. Students will learn about the formation of igneous rocks through the solidification of magma and lava, distinguishing between extrusive and intrusive varieties. Key examples include granite, basalt, gabbro, and obsidian. The lesson also covers metamorphic rocks, discussing foliation and non-foliation, with an emphasis on regional and contact metamorphism. A hands-on lab will reinforce these concepts for better understanding.

dannon
Download Presentation

Understanding Igneous and Metamorphic Rocks: Characteristics and Classification

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. September 23, 2011 Bellringer: Answer on Bellringer sheet… write out question and answer

  2. Objective: • Identify rocks using physical characteristics • Agenda: • Rock Notes • Lab 9: Rocks

  3. Form by solidification (crystallization) of melted minerals At the surface, LAVA hardens to form EXTRUSIVE rocks with tiny (FINE-GRAINED) crystals or GLASSY (no crystal) TEXTURES Beneath the surface, MAGMA hardens to form INTRUSIVE rocks with easily visible (COARSE-GRAINED) crystal texture. IGNEOUS ROCKS

  4. Granite • Light-colored, coarse- grained, no pattern • Mostly quartz, feldspar, mica, and hornblende • Often used for buildings and monuments

  5. Basalt • Dark-colored, fine- grained, extrusive • Formed where lava erupted onto surface • Most widespread igneous rocks

  6. Gabbro • Dark-colored, coarse- grained intrusive • Similar composition to basalt—plagioclase feldspar with some pyroxene and olivine

  7. 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

  8. Pumice and other igneous rocks • Light colored, frothy (many air spaces)

  9. Formed by heat and pressure changing existing rocks REGIONAL METAMORPHIC 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 Metamorphic Rocks

  10. “Foliated” rocks contain much mica and other rocks that produce layering or banding

  11. Non-foliated metamorphic rocks include marble, which comes from limestone, and quatzite, which comes from sandstone

  12. Ticket out the door

More Related