Earth science and Earth science teaching

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The AS-1 Seismometer and AmaSeis Software An
Effective Educational Seismograph
Larry Braile Department of Earth and Atmospheric
Sciences Purdue University IRIS Seismographs in
Schools Program http//www.iris.edu/hq/sis
http//web.ics.purdue.edu/braile/new/AS1AmaSeis20
08.ppt
braile_at_purdue.edu www.eas.purdue.edu/braile Updat
ed October 2011
Exploring Planet Earth
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The AS-1 Seismometer
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The AS-1 Seismometer

• Inexpensive (500) easy to set up and use
• Demonstrate how a seismograph works
• Make your own earthquake
• Monitor earthquakes local (M3), regional
  (M5), worldwide (M6.5)
• Connects to IRIS data archiving and analysis
  software (written by Alan Jones) on Windows
  computer maintain EQ catalog
• Display, filter and analyze seismograms
• Calculate epicenter-to-station distance from S-P
  times calculate magnitude

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(developed by Alan Jones, SUNY Binghamton, NY)
IRIS AmaSeis Software
24-Hour Screen Display
Extracted Seismogram
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Monitoring Earthquakes

• January 22, 2003, M7.8, Colima, Mexico
  earthquake recorded on an AS-1 seismograph and
  AmaSeis software at West Lafayette, IN. Distance
  26.01 degrees. Seismogram was filtered from
  0.001 0.1 Hz.
• .

Maintaining a catalog of recorded earthquakes is
a convenient and educational exercise associated
with educational seismograph operation. Data
entries require observation and analysis of
seismograms, retrieving information from the
internet and performing simple calculations.
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Determine distance from S-P time
Using the AmaSeis travel time curve tool to
determine the epicenter-to-station distance from
the S-P arrival times. January 22, 2003, M7.8,
Colima, Mexico earthquake recorded on an AS-1
seismograph and AmaSeis software at West
Lafayette, IN Distance 26.01 degrees.
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Drawing an arc on the globe for Oaxaca EQ for TUC
station.
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Comparison of calculated earthquake to station
distance and distance estimated from S P times
N 169 Standard Deviation 1.89 degrees
http//web.ics.purdue.edu/braile/edumod/MagCalc/A
S1Results.htm
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Calculating Magnitude
Online Earthquake Magnitude Calculator for the
AS-1 Seismograph
Inputs Distance (degrees), Amplitude (digital
units from AmaSeis screen converted to
displacement by the calculator), and wave period
(seconds).
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Comparison of AS-1 and USGS Magnitudes
MS Magnitudes N 270 Standard Deviation
0.25 magnitude units. mb Magnitudes N 520
Standard Deviation 0.26 magnitude units. mbLg
Magnitudes N 34 Standard Deviation 0.35
magnitude units.
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Comparison of AS-1 and USGS Mw Magnitudes
AS-1 mb, MS and mbLg magnitudes correlate well
with M (Mw, moment magnitude) except for the
largest earthquakes
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AS-1 Seismograph Resources
AS-1 Seismograph Information (Links) http//web.i
cs.purdue.edu/braile/indexlinks/as1.htm
Teaching Modules and Tutorials http//web.ics.pur
due.edu/braile/edumod/as1lessons/as1lessons.htm
View Near Real Time Seismograph
Displays http//www.iris.edu/amaseis/schools/
WLIN Seismograph Earthquake List http//web.ics.p
urdue.edu/braile/edumod/as1lessons/InterpSeis/EqL
ist.xls
WLIN Earthquake data for download (as large as
50MB) http//web.ics.purdue.edu/braile/new/2004.
zip also, 2005.zip, 2006.zip, 2007.zip,
2008.zip, 2009.zip, 2010.zip
Instructions for downloading 2003 (etc.) data to
the AmaSeis folder on your computer http//web.ic
s.purdue.edu/braile/edumod/as1lessons/UsingAmaSei
s/download2003.htm
Exploring Planet Earth