Birth of a Theory
After the 1906 San Francisco earthquake, slip was measured all along the San Andreas Fault.
Why It Matters
- Harry Fielding Reid was one of the founding fathers of geophysics.
- Reid was one of the scientists who put together the Lawson report on the 1906 San Francisco earthquake.
- Using the data collected, Reid developed the Elastic Rebound Theory.
- Similar to pulling on a rubber band slowly until the band finally breaks, this theory states that distant forces gradually build up stress on the Earth's plates, causing faults to break. This results in earthquakes.
Show What You Know
With the links below, learn more about elastic rebound theory. Then answer the following questions.
- USGS, Earthquakes – Shock Waves: http://www.youtube.com/watch?v=1HmpGlXHPX0
- UCSB, Introduction to Elastic Rebound Animation: http://projects.eri.ucsb.edu/understanding/elastic/intro-rebound.html
- USGS, 1906 Marked the Dawn of the Scientific Revolution: http://earthquake.usgs.gov/regional/nca/1906/18april/revolution.php
- What information was contained in the Lawson report?
- How did scientists in 1906 explain the observation that the San Andreas Fault had shifted along the length of more than 200 miles?
- What two factors caused damage to buildings in the earthquake area?
- What information did Reid use that led him to develop the elastic rebound theory?
- How does the elastic rebound theory explain how earthquakes happen?