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E I S M I C
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L E U T H S
MA T E R I A L S
TEACHING CLUES AND CUES
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Chalkboard or overhead projector, chalk or markers
Q
Student copies of Master 5.1b, Approaches to Predicting
Earthquakes
Point out that the degree
of probability is an
essential element in pre-
diction. You can predict
Q
Student copies of Master 5.1c, Levels of Generalization:
Classification Chart
Q
Back of Master 5.1c, Answer Key
with a probability of 99.9% that an
earthquake of magnitude 2 will occur
in southern California tomorrow. For
larger quakes, the degree of proba-
bility drops sharply.
P ROC E DUR E
A. Introduction
Tell students that with increasing numbers of the world’s people living
in active earthquake zones, earthquake prediction or forecasting has
been receiving more and more attention in recent years. Begin by
asking students to name some advantages of being able to predict
earthquakes. Record responses on the overhead or chalkboard. (Likely
answers will include saving lives and reducing property loss and
damage, providing guidelines for development and human settlement,
providing valuable data for the scientific community, helping people
to prepare for earthquakes on both a short-term and a long-term basis,
and allowing communities to return to normal more quickly after an
earthquake.)
Ask: Would there he any disadvantages to being able to predict or
forecast earthquakes? (Answers might include financial losses to
businesses forced to close and the anxiety people would feel if they
knew an earthquake was imminent.
Lesson Development
1. Ask: Are we, in fact, able to predict or forecast earthquakes with
any certainty? Students may have heard of some theories and attempts
at prediction, but they will also know that earthquakes have claimed
lives and property in recent years. If earthquake prediction was an
exact science, these losses would have been greatly reduced.
Remind students that while significant efforts at developing systems of
accurate prediction are underway in earthquake-prone countries like
Japan, the United States, and the People’s Republic of China,
seismologists are still a long way from accurate prediction. Point out
that of the several types of phenomena that may predict an earthquake,
many may be due to other causes and yield false alarms.
2. Organize the class into groups of three of four students each. Have
all the students in each group list these terms at the top of a blank
sheet of notebook paper: time, magnitude, place, and probability. Ask
each group to write briefly how they think these terms relate to
seismic prediction and why they are important. Also discuss the idea
of coincidence, versus that of causality. For example, a sunrise occurs
within 24 hours of every earthquake, but sunrises cannot be said to
cause earthquakes.
