The students will be able to identify different minerals, colors, sizes, and textures that appear in most intrusive igneous rocks.
The word igneous comes from the Latin word ignis, which means "fire". Igneous is used to describe rocks that crystallize out of hot molten material in the Earth called magma. When magma pushes up through Earth's crust to the surface, it is called lava. Both magma and lava cool and harden to form igneous rocks.
Made from magma. Cools inside the Earth. Cools slowly, allowing large crystals to form. Crystals can usually be seen by the unaided eye. Made from lava. Cools on the Earth’s surface. Cools quickly, forming small crystals. Need a magnifying devise to see crystals. Intrusive = In Extrusive = Exit Granite Obsidian
Types of Minerals How can you tell how many minerals are in a rock? Just by looking at them! 1.) Felsic Minerals They are light in color Colors include: gray, white, pink, or colorless They have more silica than any other mineral 65%+ 2.) Intermediate Minerals Darker than Felsic, but lighter than Mafic 55%-65% of the mineral is silica Granodiorite (Granite) 3.) Mafic Minerals Darker minerals Colors include: black, brown, dark gray, or green They have a lot of iron and magnesium in them 4.) Ultramafic Minerals Dark colors and can have some green Less than 45% silica Has lots of iron and magnesium in them
Physical Characteristics Intrusive rocks have large crystals that can be seen with the naked eye. A rock with large crystals is coarse- grained
Physical Characteristics Igneous intrusive rocks can be…. Felsic (Light colored)- Minerals are often colorless, white, gray or pink And Mafic (Dark colored)- Minerals are chiefly black, brown, dark gray and sometimes green
Other Important Intrusive Rocks Gabbro This rock is the equivalence of a Basalt which is in extrusive rocks. Coarse grained rock Granite Medium coarse grained rock How are they made? When molten magma is stuck underneath the Earth’s surface, it begins to cool and crystallize.
Building materials Counter tops (kitchens, bathrooms)
Curling stones-Thick stone disc with handle (40lbs.) used for a sport played on ice. Marbles
Gabbro. (2010, December 3). Retrieved January 23, 2011, from Wikipedia: http://en.wikipedia.org/wiki/Gabbro Granite. (2011, January 18). Retrieved January 23, 2011, from Wikipedia: http://en.wikipedia.org/wiki/Granite Hamilton, C. &. (2011). Igneous Rocks. Retrieved January 23, 2011, from scienceviews.com: http://www.scienceviews.com/geology/igneous.html Vogel, C. G. (2000). Science Explorer Inside Earth. Upper Saddle River, New Jersey: Prentice Hall. Galleries, A. (2011, January 21). The Rock. Retrieved January 18, 2011, from Amethyst Galleries: http://www.galleries.com/rocks/granite.htm