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Earthquake Machine, part 2. Mechanical Modeling to Increase Student Understanding of Complex Earth Systems. Developed by Michael Hubenthal - IRIS Consortium. Objectives. Describe global trends for Earthquake occurrence and magnitude Interpret a Gutenberg Richter plot (Frequency vs. Magnitude)
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Earthquake Machine, part 2 Mechanical Modeling to Increase Student Understanding of Complex Earth Systems Developed by Michael Hubenthal - IRIS Consortium
Objectives • Describe global trends for Earthquake occurrence and magnitude • Interpret a Gutenberg Richter plot (Frequency vs. Magnitude) • Critically analyze an argument • Describe the importance of sharing science results with peers in the science process
Developing arguments…. How many beads are in the box????
Relationship of slip to magnitude Seismic Moment Mo = fault length x fault width x displacement x rigidity Moment Magnitude = Mw = log Mo/1.5 – 10.7
B Visualizing magnitude with the model Seismic Moment Mo = fault length x fault width x displacement x rigidity Moment Magnitude = Mw = log Mo/1.5 – 10.7 In earthquake machine, this means magnitude is directly related to fault displacement 6
#1 “There are long periods of quiet between earthquakes” “Most earthquakes are huge, deadly and destructive events” #2 “There hasn’t been an earthquake in a long time; therefore the next one must be huge.” Extra credit Develop an argument either for or against one statement based on your experimentation with the earthquake machine.
Time Predictable Slip Predictable Characteristic Stress Slip Time
Calaveras Fault Data (Bufe et al., 1977)
Summary • There are many more small earthquakes than large earthquakes • There are more short time periods between earthquakes than long time periods • In the earthquake machine, the longer since the last earthquake, the larger the earthquake is likely to be • This isn’t usually true in the Earth