Rocks Assignment

Dr. Pamela Gore
Georgia Perimeter College

Objectives

1. Identify rocks using their physical and chemical properties.
2. List and define the terms used to describe the textures of igneous, sedimentary, and metamorphic rocks.
3. Identify the dominant minerals present in coarse-grained igneous rocks, and in the most common sedimentary and metamorphic rocks.
4. Explain how to determine whether a rock is igneous, sedimentary or metamorphic.
5. Explain how rocks are classified.

It would be best if this lab exercise could be done when the class has assembled for a meeting under the direction of the course leader. This lab could be done at the first meeting, or at one of the other scheduled meeting times.

Getting started:

1. Read your web course notes.

2. Read Chapter 2 in your textbook, p. 35 - 57.

3. Read Exercise 2 in your lab manual, p. 19 - 36.

Note: Lab manuals will not be available until about June 20. We will arrange for you to get a xerox of this lab in the meantime.

You may write in the lab manual, tear out the pages and turn them in, or you may xerox the pages and turn them in. If you work with a group, each person should turn in their own work. Do not turn in a xerox of someone else's work.

It is best to work in pencil because you will do a lot of erasing.

To do this exercise, you will need:

1. Ward's "Know Your Rocks" Collection

2. Ward's Rock and Mineral Test Kit

3. Hopefully you will have access to dilute hydrochloric acid from your school chemistry lab. Or you may purchase a small container of muriatic acid at a hardware store. You will need to follow any warnings or directions on the package. This is acid. It will burn through your clothing and can injure your skin or eyes. We recommend that you use safety goggles and latex or vinyl gloves when dealing with hydrochloric or muriatic acid.

   Alternatively, you can work with your course leader and he or she should be able to tell you which of the samples will react with hydrochloric acid.

Follow the instructions with your rock collection to test and identify your unknown samples.
Do not mix the specimens from the various sets until you have identified them according to the instructions.

As each group of specimens is identified, number them according to the key in the instructions. Numbers and glue are provided in your kit. Take a hole punch and punch out the number. Use Elmer's glue to apply the number to a corner of the sample on the worst looking side. Do not cover up the best looking side of the sample.

Work through Exercise 2 in the lab manual, answering the questions, using the samples in your rock collection.

Answer all of the questions.

For question 9, use a magnifying glass or handlens (or preferably a microscope, if available).
For question 12, using your 8 igneous rock samples, fill in the igneous rock identification chart on p. 28, noting their texture, color, minerals present, and determine the rock name.

For question 14, use a magnifying glass or handlens (or preferably a microscope, if available) to examine your specimen of conglomerate.
For question 17, if hydrochloric acid is not available, you may skip this, or post to the bulletin board to have your instructor tell you which ones fizz.
For question 18, using your 8 sedimentary rock samples, fill in the sedimentary rock identification chart on p. 30.
Your book uses the word "detrital" which is basically a synonym for clastic or terrigenous.

In question 21, you are to circle either the word slate or the word schist.
In question 22, circle either the word phyllite or gneiss.
For question 23, use either schist or geniss, but tell which one you are using.
For question 24, examine quartzite and marble.
For question 25, using your 8 metamorphic rock samples, fill in the metamorphic rock identification chart on p. 33.

For review, please answer the summary page on p. 35-36.

Turn the answers to these questions in to your course leader. Please check with your course leader to see the best way to do this. Options include fax, US postage, e-mail attachment, dropping them off in person, etc. Please keep a copy for yourself. This is good "insurance" in case things get lot in the mail, or in case you need to study your answers before your graded paper is returned.

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Page created by Pamela J.W. Gore
Georgia Perimeter College,
Clarkston, GA

June 4, 2000