HR: 1340h
AN: ED13C-1157 [Abstracts]
TI: Stick-Slip, Gutenberg-Richter, Chaos and Predictability: A Classroom Demonstration
AU: * Moore, W B
EM: bmoore@ess.ucla.edu
AF: University of California, Los Angeles
Department of Earth and Space Sciences and Institute of Geophyics and Planetary Physics, 3806 Geology Bldg.
BOX 951567, Los Angeles, CA 90095-1567
United States
AB:
This demonstration illustrates many of the phenomena
associated with earthquakes in the Earth's crust, while
engaging students (and the instructor!) in an enjoyable
physical activity. The demonstration is a scaled up
slider-block model, with students as the blocks and the
instructor as the driver. It is suitable for elementary
students through college age students, but some of the
concepts (power-law, statistical prediction) are
high-school level. Materials may vary depending on the
size of the students and of the class. An example using
college students consists of four 2x2 pieces of 3/4 inch
plywood, four chairs set on the pieces of plywood, four
bungee cords, and eye-hooks screwed into the front and back
edges of each piece of plywood. Materials may vary
depending on the roughness of the floor, the size of the
students, and availability, but the key properties are
elastic connections (the bungee cords) and a frictional
contact between the blocks and the floor (for smaller
students, their feet work just fine). The slider blocks
are assembled into a chain by linking them to each other
with bungee cords hooked through the eye-hooks. The
demonstration begins with a single block with one student
on the block. Using heavier and lighter students, and
pulling the lead cord faster or slower, the instructor can
demonstrate pseudo-periodic behavior and establish the
relationship between friction and driving stress. By
adding a second block to the chain, the concept of
triggered events can be demonstrated. By adding a third
and fourth block, an event size spectrum can be established
which will follow a power law. The size of each event will
not, however, be predictable, nor will the blocks involved,
thus demonstrating that statistical measures of even
probability are required.
DE: 0805 Elementary and secondary education
DE: 0810 Post-secondary education
DE: 0845 Instructional tools
DE: 7209 Earthquake dynamics (1242)
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
SC: Education and Human Resources [ED]
MN: Fall Meeting 2005