Department
of Earth Science |
Northeastern
Illinois University
INTRODUCTION TO EARTH SCIENCE
ESCI 121
Section 06
Fall 2009
Department
of Earth Science |Northeastern
Illinois University
Review for Exam #3
(November 12, 2009)
Dr. Sanders
For the exam, you should be able to do the following:
VOLCANOES
w List the
geotectonic settings in which volcanoes occur (subduction zones, divergent
zones, hotspots).
w
Tell why volcanoes occur at
each of these settings.
w Tell what
makes rock melt in the crust and mantle settings where volcanoes occur.
Describe the process in terms of changing temperature, changing pressure, and
introduction of "impurities" (water and sediments) into the melt.
w Draw
a graph illustrating the varying conditions that lead to rock melting.
w Explain
what a hotspot is, and tell how it fits into a geotectonic framework. Give an
example.
w
Describe the differences between lava of mafic
and felsic composition, and tell how these differences lead to variation in
these aspects:
q
form/shape/profile of the volcano
q
type of material erupted, and
q
the volcano's "eruptive style".
w
Define the terms pahoehoe and
aa, and tell where these materials might be found.
w
After viewing the Raging Planet film
"Volcano", describe some of the strategies people use to cope with life next to
a volcano.
LATITUDE AND LONGITUDE
w Describe the
longitude and latitude coordinate system for locating points on Earth's surface.
w
Find the approximate (degrees) latitude and
longitude of a general area using a world map.
w
Explain how the measurement units of degrees,
minutes, and seconds are used to indicate latitude and longitude.
w
Find precise latitude and longitude coordinates
of a specific site using a topographic quadrangle map.
w Explain what is meant
by "7.5 minute series" in reference to a topographic quadrangle map.
w Log in to the
class wiki and add your name to the "Earthquake Maps" list. Find the
latitude and longitude coordinates of the study area for which you sign up.
w Be
informed enough about use the USGS earthquake information site to complete the
homework assignment on Earthquake Maps.
EARTHQUAKES
w
Explain the difference between the focus
of an earthquake, and the epicenter.
w
Tell what the term magnitude
means as applied to earthquakes.
w
Explain how a seismometer works.
w Explain why every
seismograph includes at least three seismometers.
w Describe P-waves
and S-waves and explain the differences between them.
w Demonstrate how to use
a seismic P-S lag (time difference) to determine the distance to
an earthquake epicenter.
w Show how to locate the
epicenter of an earthquake using seismograms from three different stations.
Explain why it is necessary to use data from at least three stations.
w After viewing some of the
videos and animations of
the Indian Ocean tsunami of December 26, 2004, research seismograms from the
event.
w Use seismograms to find the epicenter of
an earthquake using the Indian Ocean tsunami as an example. (Extra copies of
the map,
the
seismograms , and the
P-S lag (time
difference) graph are linked to this page. This exercise is abridged from
an
exercise copyrighted in
2004 by Dave Robison and Steve Kluge.)
EARTHQUAKES AND GEOTECTONICS
w
Using the earthquake maps the class produced,
arrange them in meaningful groups based on the patterns of earthquake epicenters
and based on the patterns of focal depths you observe in each.
The
worksheet appears at this link.
