GO 324A Rocks and Minerals
www.emporia.edu/earthsci/amber/go324/rock.htm
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Emporia State University |
GO 324A Rocks and Minerals
www.emporia.edu/earthsci/amber/go324/rock.htm
|
Emporia State University |
Rocks are a natural aggregate of one or more minerals. The study of rocks draws upon mineralogy, geology, paleontology, chemistry, and physics. Ascertaining the textures, structures, mineral components, and organic remains when present are all key to identifying rocks. Mineral components and organic remains may be determined with the unaided eye, but often times positive identification will require high magnification or devices more sophisticated than a microscope. Texture refers to the size, shape, and arrangement of component constituents. Structure may describe the shape, dimensions and articulation of the component constituents (Simon & Schuster, 1978, p. 415). Textural and structural terms may vary with different rock classifications. Structures are usually visible on a geologic scale, whereas textures are on a hand specimen scale. Texture is the result of the formational environments and structures, the result of deformations.
Visit Identifying Rocks in Kansas and Colorado, http://www.geospectra.net/fieldgeology/rocks.htm, for some pictures of rock types and clues to identification.
There are three classifications of rocks found on Earth, igneous, sedimentary, and metamorphic. Earth is divided into a crust, mantle, and core, with the upper mantle and crust together referred to as the lithosphere. The lithosphere is divided into plates that are bounded by faults, subduction zones, and spreading centers. Even though the oceanic crust is primarily basalt and continental crust is primarily granite, the upper 10 miles of the lithosphere consists of 95% igneous or their metamorphic equivalents, 4% shale, 0.75% sandstone, and 0.25% limestone (Klein and Hurlbut, 1999, p. 221). Therefore, igneous and metamorphic rocks dominate the lithosphere volumetrically and sedimentary rock is primarily exposed as a thin covering over much of the Earth's continents. Raymond (1995) stated that a thin veneer of sedimentary rock covers 66% of the continental crust, while the remaining surficial exposures are equally divided between igneous and metamorphic (p. 3).
For an animated views of rocks and rock processes visit:
This page originates from the Earth Science department for the use and benefit of students enrolled at Emporia State University. The curriculum is © by the author, 2001-2009. Last update 18 July 2009. For more information contact the course instructor, Dr. S. W. Aber, e-mail: saber@emporia.edu
To understand copyright, visit lcweb.loc.gov/copyright/. All rights reserved. Susan Ward Aber. 
Oooo an opportunity for you! Can you guess how deep into the mantle we have seen? Which minerals are found in these deep seated rocks? To answer these questions, visit World's Deepest Rocks Recovered, http://news.bbc.co.uk/1/hi/sci/tech/755631.stm. If you are enrolled in the course, send a one-page website summary to saber@emporia.edu for one extra-credit point on the second exam. Place GO 324 second exam point in the subject line of the email, and I must receive this by October 6.
Suggested Reading and Interesting Links
Suppliers
Petrology Introduction
www.emporia.edu/earthsci/amber/go324/intro.htm
Minerals
www.emporia.edu/earthsci/amber/go324/mineral.htm
Rocks
www.emporia.edu/earthsci/amber/go324/rock.htm
Igneous
www.emporia.edu/earthsci/amber/go324/igneous.htm
Sedimentary Rock
www.emporia.edu/earthsci/amber/go324/sediment.htm
Metamorphic Rock
www.emporia.edu/earthsci/amber/go324/metamor.htm
Course Field Trip
www.emporia.edu/earthsci/amber/go324/field_trip.htm
Course Syllabus
www.emporia.edu/earthsci/amber/go324/syllabus.htm
To the beginning!