Review for Exam 2

Department of Earth Science |Northeastern Illinois University

INTRODUCTION TO EARTH SCIENCE
ESCI 121
Section 05
Spring 2009
Review for Exam #2 (February 24, 2009)                                                                                                         Dr. Sanders

The exam will be open book, open notes (no computers). At least part of the exam will be done in a group.

For the exam, you should be able to do the following:

Minerals

w   List and explain the mineral properties most commonly used to describe/identify minerals:

        ▫ hardness        ▫ luster            ▫ color                 ▫ cleavage         ▫ specific gravity (density)
        ▫ streak             ▫ taste             ▫ magnetism      ▫ reaction with acid (effervescence or odor)

w   Demonstrate that you can test an unknown mineral sample for each the mineral properties above, and use a mineral key to identify an unknown sample.

w   Define mineral cleavage.

w   Describe mineral cleavage (Beware! There is an error on this page!) in terms of how many planes of cleavage occur and at what angles.

w   Recognize stair-step or stepped cleavage. The third diagram on this page shows how it occurs. While you're here, take a look at the short videos part-way down the page.

Rock Your State! In-class work

w   Working with 2-3 others, make a list of all the kinds of rocks and sediments found in the states you researched.

w   Create a master list (using sticky notes) of all the rocks/sediments represented for all the states in your group.

w   For each item on the list, categorize it as a sediment, igneous rock, sedimentary rock, or metamorphic rock.

w   Before you go on, write out on notebook-sized paper a statement of how each type of rock is formed.

w   Back to the poster sheets: For each type of rock (ig, sed, meta), subdivide the group into smaller classifications.

w   Put each kind of rock into its classification.

w   For sediments, organize the materials according to some logical principle. (What is it?)

Minerals

w Explore and describe the reaction of minerals to acid.

w Name the two minerals that effervesce with acid, and explain how to tell them apart.

Sedimentary Rocks

w   Explain how sedimentary rocks form.

w   List three clastic (detrital) sediments, and explain how to identify them.

w   List 5 chemical sediments.

w   Fill in the empty boxes:

CLASTIC SEDIMENTARY ROCKS	SEDIMENT NAME AND SIZE OF GRAINS	ROCK NAME	HOW WILL YOU RECOGNIZE IT WHEN YOU SEE IT AGAIN?
	Gravel, bigger than 2 mm
		Sandstone
	Clay or silt, grains so small they are not visible to the unaided eye		Flat shape, thin layers
CHEMICAL SEDIMENTARY ROCKS	MINERAL MAKING UP THE ROCK	ROCK NAME	HOW WILL YOU RECOGNIZE IT WHEN YOU SEE IT AGAIN?
	Calcite
		Dolostone, rock dolomite, or just dolomite	Fizzes only when powdered, some samples have pinpoint sized holes
	Gypsum
		Rock salt

w   Define the following terms and explain their significance to sedimentary rock-forming processes:

     ▫ lithification           ▫ cementation                ▫ chemical sediments ▫ clastic (detrital) sediments
      ▫ compaction         ▫ chemical sedimentary rock      ▫ clastic (detrital) sedimentary rock

w   Using the results of our "Rock Your State!" investigations, describe how sedimentary rocks are classified.

Department of Earth Science | Northeastern Illinois University