GO 240 Hand Specimen Petrology
Dr. Susan Ward Aber

www.emporia.edu/earthsci/amber/go240/intro.htm

Emporia State University
Emporia, Kansas USA
Earth Science Department


2008 Hand Specimen Petrology Class at Rose Dome
left to right, back row: Sarah, Amy, Nikki, Susie, Gayla
left to right, front row: Brenda and Graham (Amy W. not pictured)

Petrology is a branch of geology that deals with the origin, occurrence, structure, and history of rocks (Bates & Jackson, 1987, p. 497). It is a term used to encompass the study of rocks, which is based on observation and classification, and subdivided into petrography and petrogenesis. Petrography is the study of the description and systematic classification of rocks in thin sections, whereas petrogenesis covers the histories of formation and origins of rocks (Raymond, 1995, p. 2).

This course is an introduction to petrology and focuses on recognition, terminology, and classification of minerals, rocks, and sediments. The emphasis is on sight identification and description using only simple equipment. The two-credit-hour course is intended for any undergraduate with an interest in Earth Science (ES) and especially recommended for Earth Science and Education majors. It is taught on the Emporia State University campus and these webpages are meant to be complementary to the course.

An ESU spring semester schedule of events can be found at www.emporia.edu/regist/enroll/syll.htm and generalized course information, www.emporia.edu/esuclass/index.htm. Academic dishonesty, which includes cheating and plagiarism, is not tolerated in this course and penalties will result. Review the ESU policy at www.emporia.edu/esuclass/dishones.htm. In addition,

Emporia State University will make reasonable accommodations for persons with documented disabilities. Students need to contact the Director of Disability Services, http://www.emporia.edu/disability/, and the professor as early in the semester as possible to ensure that classroom and academic accommodations are implemented in a timely fashion. All communication between students, the Office of Disability Services, and the professor will be strictly confidential.

Information specific to this course follows. Feel free to browse the information and if you are enrolled, please email me at saber@emporia.edu and introduce yourself. Place GO 240 introduction in the subject line, provide me with your preferred email address, and remind me to add two substitution points to your first test for following instructions!

This course meets Tuesdays, 3:00-4:50 p.m. in Science Hall room 128. My office is in Science Hall, 109A. The required textbook is a classic, first printed in 1978 with over 20 printings since then.

Chesterman, C. W. 1979. Audubon society field guide to North American rocks and minerals. Alfred A. Knopf. Obtain the newest printing if possible.

In addition to the book, the purchase of a triplet loupe with 10X is strongly recommended. Read about these magnifiers at About.com geology, http://geology.about.com/library/products/aabyb-magnifiers.htm. A BelOMO 10x Triplet Loupe Magnifier is a reliable lens (http://www.belomo.us/). Many online websites offer this brand and you should search for the best price!

Welcome to Hand Specimen Petrology!

A rock is an aggregate of one or many differentiated or undifferentiated minerals. For example, granite is primarily made up of differentiated quartz, mica, and feldspar, and each mineral can be clearly seen in hand specimen. In contrast, limestone consists almost entirely of undifferentiated calcite, where the calcite can be determined through testing but not clearly recognized as a crystal in hand specimen. Minerals are the main constituent of rocks and are naturally occurring, macroscopically homogeneous, and solid substances with a definite chemical composition and crystalline structure. It is usually assumed minerals are of an inorganic origin, but exceptions occur as in the case of pearl. A mineral may be simple, such as copper, which is a native element composed of... copper! A mineral may be complex, such as tourmaline, a silicate of boron and aluminum composed of Na (Mg, Fe)3Al6(BO3)3(Si6O18)(OH, F)4 with a ring-silicate or cyclosilicate crystalline structure.

There are over 4,000 known minerals, but only about 20 make up some 95% of all rocks. This course will examine some of the more common minerals and rocks, with a focus on specimen identification. Minerals will be presented first because they are the foundation of rocks. Rocks are divided into one of three major classes, igneous, sedimentary, and metamorphic, and rock specimen identification will comprise the remainder of the course. If time permits, minerals valued as gemstones will also be introduced or you can read up on gems at www.emporia.edu/earthsci/amber/go340. Gemstones are minerals or rocks that possess an ornamental valuation, based on beauty, durability, and a degree of rarity (Chesterman, 1978, p. 8, 9).

Why is the study of rocks and minerals important? An understanding of Earth's 4.5 billion year history and formation is derived from discovering the differences between rock types and mineral formation. There are primarily sedimentary rocks exposed at the surface in Kansas. However, 1.2 billion year old granite and 88-90 million year old contact metamorphic rocks exposed at the surface in Kansas as well. In addition to exploring and understanding Kansas and the planet we live on, minerals and rocks are of great economic importance and humanity depends on a steady supply to live!

If you are enrolled in this course and reading this before May 2008, I have a deal for you... up to 4 substitution points will be awarded on the final exam when you email me a one-page summary of the interactive online video of Spirit and Opportunity rover excursions at http://www.pbs.org/wgbh/nova/mars/upclose.html. Be sure to include rock types found and instruments used on Mars to detect the rocks and structures. Happy browsing and roving in this course!

Recommended References and Notable Links

Return to the top.

Petrology Introduction
www.emporia.edu/earthsci/amber/go240/intro.htm 		Minerals
www.emporia.edu/earthsci/amber/go240/mineral.htm
Rocks
www.emporia.edu/earthsci/amber/go240/rock.htm 		Igneous
www.emporia.edu/earthsci/amber/go240/igneous.htm
Sedimentary Rock
www.emporia.edu/earthsci/amber/go240/sediment.htm 		Metamorphic Rock
www.emporia.edu/earthsci/amber/go240/metamor.htm
Field Trip 2006
www.emporia.edu/earthsci/amber/go240/trip06.htm

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, 2001-2008. Last update 28 April 2008. For more information contact the course instructor, Dr. S. W. Aber, e-mail: saber@emporia.edu

To understand copyright, visit www.wipo.int/about-ip/en/copyright.html and lcweb.loc.gov/copyright/. All rights reserved. Susan Ward Aber.