Some notes on how to do well on essay exams.

Your answers to the essay questions should be written in complete sentences. You should restate the question at the beginning.
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For example:   Sample Review Guide:  What is a bicycle?  What is a motorcycle?
Sample Test Question:  Describe the similarities and differences between bikes and motorcycles.
Sample Essay Answer:
A bicycle and a motorcycle have much in common, but there are also significant differences.  Both are machines with two wheels that are used for transportation.  The wheels are lined up one in front of the other.  In both cases, the person who operates the machine commonly sits in a seat that is located between the front wheel and the back wheel.  When power is applied to turn some gears that turn the back wheel, the machine can move forward.  The operator steers the machine in the direction they want to travel by turning handle bars attached to the front wheel.  This is possible because the front wheel pivots on the frame of the machine.  However, a motorcycle is larger, heavier, more complex, and more expensive than a bicycle.  This is because a motorcycle is powered by a motor, much like a car, whereas a bicycle is powered by a human being.
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Review for Midterm Exam

You should be familiar with the following ideas and concepts:

How did the universe, solar system, and earth form?  How old do scientists estimate the universe to be?  How old do scientists estimate the earth to be?  Describe the internal structure of the earth today.  Is this the same as it has always been?

What is an atom?  What is the structure of an atom?  What are protons, neutrons, and electrons?  What is an element?  An ion?  What is ionic bonding?  What is covalent bonding?  How strong is each type of bond?

What is the definition of a mineral?  What is a rock?  What are some physical properties of minerals?

You should memorize Mohs hardness scale.

You should be able to identify common minerals (see review sheet for quiz).
 

What are the three major rock types?  What is the rock cycle?

You should be able to distinguish between igneous, sedimentary and metamorphic rocks.

How do igneous rocks form?

What is the difference between intrusive and extrusive igneous rocks?

What do the terms “mafic” and “felsic” mean?

Which minerals are mafic minerals?  Which are felsic minerals?

What does color index mean?

What criteria to you use to classify/identify igneous rocks?

Be able to describe (and give the terms for) the different kinds of textures that can be seen in igneous rocks.

Be able to describe (and give the terms for) the different kinds of igneous intrusions that can be formed.

Be able to identify the common igneous rocks.

How do rocks “weather?”

What is the difference between weathering and erosion?

What gets produced from chemical weathering of the minerals in granite?

What gets produced from chemical weathering of the minerals in basalt?

How do sedimentary rocks form?

What is the difference between detrital (or clastic) sedimentary rocks and the chemical and biochemical sedimentary rocks?

What criteria do we use to classify/identify sedimentary rocks?

What are the major size ranges of clastic particles?  (gravel, sand, silt and clay)

What is the difference between conglomerate, sandstone, siltstone and shale?

What do we mean by “degree of rounding” and “degree of sorting” when we talk about sedimentary rocks?

Be able to identify common sedimentary rocks.

How do metamorphic rocks form?

What factors influence what type of metamorphic rock will form?

What is metamorphic facies?  Metamorphic grade?

Describe what happens to shale as it is metamorphosed at higher and higher grades.

What kinds of metamorphism would you expect to find in different plate tectonic settings?

What is the difference between contact metamorphism and regional metamorphism?

Be able to identify common metamorphic rocks.

What is the crust and where is it located?  How about the mantle?  The core?  What is the lithosphere?  What is the asthenosphere?  How thick is the oceanic crust compared to the continental crust?  What do we mean by plate when we say “one of the earth’s plates?”

What are the major types of plate boundaries?  What types of geologic activities are common at various types of plate boundaries?  How fast do plates move?

What is magma?  Where and how does it form?  What is lava?

What kinds of materials erupt from volcanoes?  (Lava and pyroclastic material.)
How does the amount of gas in the magma affect whether the eruption will be a “quiet” one with mainly lava flows, or an explosive one with mainly pyroclastic material ejected?  How does the composition and the viscosity of the magma affect this?

What are the main types of volcanoes? (Shield volcanoes, cinder cones, domes, and composite cones or stratovolcanoes) What are their shapes?  Of what kinds of volcanic materials are they made?  How does what they are made of affect their shape?

Where do most of the world’s active volcanoes occur? (In terms of plate tectonics)
What kind of volcanic eruption is most common at divergent plate boundaries, especially where two oceanic plates are diverging?  What type of volcanoes are commonly found on the over-riding plate at a subduction zone? (for example, in the Pacific Northwest of the United States).  What kinds of volcanoes are found over “hot spots?”  (Hawaii is now over a hot spot).

Can we predict volcanic eruptions?  Are earthquakes related to volcanic eruptions?  How?  What can happen to the earth’s surface when magma is rising close to the surface?

How can you determine the relative ages of rocks using physical relationships between rocks?

Be able to describe the “laws” that can help you determine relative ages of rocks.

Be able to look at a geologic cross-section and rank rocks in order of youngest to oldest using clues in the rocks.