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Earthquakes, Volcanoes, and a Modern Journey to the Center of the Earth Michael Wysession Professor of Geophysics, Dept of Earth and Planetary Sciences Washington University, St. Louis, Missouri. PLATE. “Plate Tectonics,” The Basic Idea:. Locations of the Major Tectonic “Plates”.
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Earthquakes, Volcanoes, and a Modern Journey to the Center of the Earth Michael Wysession Professor of Geophysics, Dept of Earth and Planetary Sciences Washington University, St. Louis, Missouri
Following the 1755 Lisbon earthquake on All Saint’s Day, the Spanish Inquisition burned people at the stake to atone for the city’s sins.
More reasonable assessment, based upon actual seismicity The Global Seismic Hazard Assessment Program (GSHAP), with the support of the International Council of Scientific Unions (ICSU), and endorsed as a demonstration program in the framework of the United Nations International Decade for Natural Disaster Reduction (UN/IDNDR).
Earthquakes occur where earthquakes occur, and… Earthquakes occur where seismometers exist
Earthquakes occur where earthquakes occur Earthquakes occur where seismometers exist Almost no seismometers!!
The NMFZ is associated with the Reelfoot Rift – a failed rift zone that was active 750 million years ago, as the supercontinent Rodinia began to break up.
The Reelfoot Rift is a region of lower elevation (which is why the Mississippi River flows down through it!).
Notice all the earthquakes EAST of the NMSZ! The NMSZ might be finished (for now?). It might be time for a different failed rift to undergo some continental creaking. o Historicalo Instrumental
Wabash Valley Seismic Zone earthquakes: The latest - Mw 5.2 on April 18, 2008 (last Friday!)
A DEVASTATING EVENT: THE SUMATRA EARTHQUAKE OF DECEMBER 26, 2004
Indian Plate Burma Microplate Sumatra
Northward Motion of India Deforms the Entire Region Sumatra Earthquake
Banda Aceh: Before….
Banda Aceh: Before…. and After…..
Massive landslides in places like the Canary Islands could cause enormous Atlantic tsunamis!
There have also been Giant Undersea Landslides in the Puerto Rico Trench!!!!
For Large Earthquakes, Seismic Waves Circle the Earth for Months to Years, Making it Ring Like a Gong. (Earth’s Lowest Note, With a Period of ~54 Minutes, is an E, Twenty Octaves Below Middle E on a Piano.) Courtesy of J. Tromp
Can Seismologists Predict Earthquakes? (Only one earthquake was ever successfully predicted: 1975 Tangshan, China)
Lack of success reminiscent of New York City “bear gap” hypothesis