Download Exam 1 Study Guide - Napa Valley College

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Exam 1 Study Guide
Physical Geology, Fall 2012
What to study:
1) Textbook - chapter review questions, vocabulary words. Several questions from each chapter will be on the test.
2) Lecture material - I recommend rewriting your notes, making flash cards, forming study groups to quiz your
peers.
3) Study hints: write out the essay questions first and rewrite them several times to help commit to memory, then go
through the rest of the study guide. Download all lecture notes and review them by writing out key parts and
quizzes your peers. Draw sketches.
Exam format:
The exam will be about 30 multiple choice questions, a few short answer questions, and about four essay questions.
Many end of the chapter questions will be included as multiple choice and short answer questions.
Time duration of exam: 1 hour and 20 minutes. This exam is open brain but closed book and closed notes. You
will need only a #2 pencil and scantron for 50 questions. You will write short essay questions right on the test in
pencil or pen.
Some Vocabulary, Concepts, and Questions from Notes:
Chapter 1 Intro
What is physical geology and historical geology?
Why is knowledge of earth and geology important and useful? Name some natural disasters?
What is Catastrophism and Uniformitarianism. Who first established the doctrine of Uniformitarianism?
How old is the earth?
What is a hypothesis and a theory? What is the difference between them? How do they relate to the scientific
method?
What are the four “spheres” and what does each include?
Heat engines – what are the two major sources of energy for the Earth? Where does the internal energy come
from?
Rock cycle – be able identify all the items on the rock cycle such as rocks and magma as well as the processes
such as crystallization.
Know the names and characteristics of the interior structure of earth based on both compositional and
mechanical layering: Crust – two types – continental and oceanic, Mantle, Inner Core, Outer Core,
Lithosphere, Asthenosphere
Earth’s largest surface features: continents, ocean floors, mountain belts, stable interior shields and stable
platforms, continental shelf, continental slope, abyssal plains, oceanic trenches, mid-oceanic ridge and
seamounts.
Where is the mid-oceanic ridge, what is happening there, why is it so important?
What is Pangea? When did it form?
What is mantle convection and what is it responsible for?
Chapter 2 - Plate Tectonics
Terms: crust, mantle, core, lithosphere, asthenosphere, continental shelf and slope, abyssal plain, mid-oceanic ridge,
oceanic trenches, Pangea, continental drift, sea-floor spreading, paleomagnetism, and plate tectonics
Know the early hypotheses and early evidence proposed by Alfred Wegener for continental drift. What finally provided a
mechanism for continental drift?
What is paleomagnetism and seafloor spreading, why are they important, and what do they show us about the movement
of the plates?
Know the major plates and their location.
Know a lot about major plate boundaries – transform, divergent, and convergent. Of the convergent, know all about the
oceanic-oceanic, continental-oceanic, and continental-continental types of convergent boundaries. This is important.
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Know where and how the magma is made, how plates are being made or consumed, location of earthquakes and
volcanoes, the relative movement directions, etc.
Know the location of the San Andreas, Hayward faults, Cascadia subduction zone, and location of the three major plates
in California – North American Plate, Pacific Plate, and Juan de Fuca plate.
What is rifting, a rift valley, and the East African Rift Valley?
Chapter 3 - Minerals
Define a mineral, crystalline structure, rock, atom, element, nucleus, and subatomic particles (proton, neutron,
and electron).
What is a molecule, ion and isotope, atomic number, atomic mass, and radioactive decay?
Know the basic abbreviations for the key elements used in class (i.e. Fe is iron, Mg is magnesium, Na sodium,
Si silicon, O is oxygen, and the molecule SiO2 is called silica and has 1 atom of silicon and two of oxygen)
What is crystalline structure and why is it important?
What are the three most common elements in the crust and their percentages? What are the most common 3
minerals in the crust and their percentages?
Mineral types – what are silicate minerals and the silica tetrahedral?
How would you characterize the two major silicate groups – felsic (often light colored) minerals vs. mafic
(often dark colored) minerals?
What are reserves vs. resources?
What was mined at the New Almaden Quicksilver Mine in the San Jose area, what was it used for, what
negative impact does it have on the San Francisco Bay?
Chapter 4 – Igneous Processes
What is magma and lava and magma chamber? What are Volcanic vs. Plutonic igneous rocks? And intrusive
vs. extrusive?
What are the three components of magma?
How do we know when an igneous rock is plutonic (intrusive)? What are the aphanitic (fine-grained) vs.
phaneritic (coarse-grined) textures? What do these textures tell you about the rate of cooling of the magma?
Classifying igneous rocks – how composition and texture are used to identify granite, basalt, andesite,
rhyolite, pumice, obsidian etc.
Composition (silica and Fe and Mg content), characteristics, viscosity, and dominant minerals in felsic,
intermediate, mafic, and ultramafic magma/lava and igneous rocks
Cooling history and extrusive or intrusive
Some common igneous rocks and which compositions they represent. Also, know the special rocks like –
obsidian, pumice, pyroclastic tuff, etc.
Factors influencing melting of rocks and crystallizing of magma.
Geothermal Gradient, factors influencing partial melting of rocks – such as temperature and pressure. What is
decompression melting and wet melting (hint: they are both a form of partial melting)? What is partial
melting? What sort of tectonic settings are decompression melting and wet melting found?
During the demonstration video shown in class, how did water boil at room temperature?
What is Bowen’s Reaction Series? What is magma differentiation?
Describe the three ways magma can change from mafic to more felsic – including magma differentiation,
assimilation, and magma mixing.
Ultramafic mantle rocks will partially melt to make a magma with _____ composition.
Mafic rocks (like basalt) will partially melt to make a magma with _____ composition.
Chapter 5 – Volcanoes
Factors that determine a volcanoes eruptive violence. Especially the role of magma composition and
viscosity.
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Some examples of mafic lava flows such pahoehoe, aa, and pillow basalts. What are their characteristics and
how do they form?
What is a pyroclastic flow, what volcanoes are they associated with, and what are the flows made of?
Describe some important features of volcanoes such as vent, crater, caldera, pipe, and magma chamber.
Be able to describe the three major types of volcanoes – shield, composite, and cinder - and provide a list of
characteristics of each including typical location.
How do flood basalts form? What are lava plateaus? How do calderas form?
Land forms or igneous structures (dikes, plutons, batholiths, volcanic necks, plutons, batholiths, etc)
Describe the igneous activity at convergent and divergent boundaries. Be able to identify features from a
drawn side view of these. What is a hotspot?
What happened at Montserrat? What happened at Pompeii? What are pyroclastic flows?
What are lahars and where might they occur on the west coast of the U.S.?
When and how did Mount St. Helens explosively erupt? Why? What tectonic process generated the magma
for Mount St. Helens?
Potential Essay Questions 1) Draw the rock cycle, including 5 boxes representing the materials of the Earth, and 5 processes between these
boxes. Also include the arrows showing the direction of movement from one material to another.
2) List the 4 most common elements and 6 most common minerals in the crust. What elements are more
common in felsic and mafic silicate minerals?
3) Sketch a side-view (or cross-section) of a subduction zone. Draw and label the oceanic and continental
lithosphere, asthenosophere, crust, mantle, trench, arrows showing direction of movement on both lithospheric
plates, location of wet melting of the asthenosphere, and magma. Draw the relative thickness of the Earth’s
layers with accuracy. Consider whether wet melting or decompression melting would be most appropriate
form of melting for this sketch. Choose one and precisely show the location of this.
4) Sketch a side-view (or cross-section) of a mid-oceanic ridge. Draw and label the oceanic and continental
lithosphere, asthenosophere, crust, mantle, arrows showing direction of movement on both lithospheric plates,
location of decompression melting of the asthenosphere, and magma. Draw the relative thickness of the
Earth’s layers and relative shape of the mid-oceanic ridge with accuracy. Consider whether wet melting or
decompression melting would be most appropriate form of melting for this sketch. Choose one and precisely
show the location of this.
5) Draw or list the layers of the earth by their chemical composition. Show the approximate chemical
composition of each layer and show how some of these layers make up the lithosphere and asthenosphere.
drawing will be useful here but not required.
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6) Compare and contrast granite and rhyolite using both texture and composition. Where are both of these rocks
originally formed (i.e. minerals crystallized) and how do they relate to a composite volcano.
7) What is a felsic magma? Describe the following about this felsic magma – composition, viscosity, one rock it
might make, what type of volcano might form from it, and what type of crust would it mostly likely be found
on?
8) Contrast (i.e. show how they are different) volcanoes found in the Cascade Range located on the U.S. west
coast with the volcanoes found at Hawaii. Make a bulleted list for the Cascades and Hawaii. Make sure to
include the following: type of tectonic boundary present, composition of lava, degree of explosiveness of
eruption, viscosity of magma, list one rock you might find at each volcano.
9) Use Bowen’s Reaction Series to describe how partial melting works. And how a basaltic magma is created by
partial melting of mantle rock at the mid oceanic ridge.
10) What is hotspot volcanism and how does it relate to the volcanoes in Hawaii?
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