30 Years of Earthquakes in Japan: 1990 - 2019

The nation of Japan lies above a tectonic plate boundary called a “subduction zone” where the Pacific and Philippine Sea Plates grind beneath the Eurasian Plate. This type of plate boundary can create volcanoes, such as Japan’s many volcanoes including Mt. Fuji. Subduction zones can also generate megathrust earthquakes beneath the seafloor that cause devastating tsunamis. Many such earthquakes and tsunamis have struck Japan including the 9.1 magnitude earthquake that caused a devastating tsunami on 11 March 2011. This earthquake, the largest ever measured in Japan, produced six minutes of intense shaking starting at 14:46 local time. The tsunami that followed caused widespread devastation and over 17,000 deaths in Japan, where waves reached over 40 m or 130 ft. high. Outside of Japan the tsunami also killed one person in Papua, Indonesia and rose to greater than 5 m or 16 ft. in the Galapagos Islands (Ecuador), greater than 2m or 6.5 ft. in Indonesia, Russia's Kuril Islands, and in Chile, and rose to greater than 1 m or 3 ft. in Costa Rica, the Marquesas Islands (French Polynesia), Mexico, Papua New Guinea, and Peru. In the United States the tsunami rose to more than 5 m or 16 ft. in Hawaii, more than 2 m or 6.5 ft in California and Oregon, and more than 1 m or 3 ft. in the U.S. island territories of Midway and Saipan (Northern Mariana Islands). The tsunami also killed one person in Crescent City, California..
This animation begins with a map of plate boundaries including the subduction zone between the Pacific plate and the Eurasian and Philippine Sea Plates. It will then show the earthquakes in sequence as they occur for 30 years beginning in the year 1990, about 21 years before the 2011 earthquake, and continues through the end of 2019, showing the nearly nine years of activity since then. Each earthquake is represented by a circle whose size indicated magnitude and color indicates depth within the earth. It will then conclude with a summary map showing all of the earthquakes in the animation. Several significant earthquakes, including tsunami-generating earthquakes, occurred during this period:
12 July 1993 -- M7.7 -- Hokkaido, devastating tsunami at Okoshiri Island
28 December 1994 -- M7.7 -- offshore Sanriku, non-damaging local tsunami
17 January 1995 -- M7.3 -- Kobe, widespread earthquake damage
4 May 1998 -- M7.5 -- Ryuku Islands
25 September 2005 -- M8.3 -- Hokkaido, local tsunami
15 November 2006 -- M8.3 -- Kuril Islands, ocean-crossing tsunami
13 January 2007 -- M8.2 -- Kuril Islands
11 March 2011 -- M9.1 -- Tōhoku, locally devastating ocean-crossing tsunami
30 May 2014 -- M7.8 -- Bonin Islands
The U.S. Pacific Tsunami Warning Center (PTWC) will issue tsunami alerts for any potentially tsunami-causing earthquake in the Japan region. These alerts will be posted to:
tsunami.gov
The seismic instrument networks that PTWC uses to detect and analyze earthquakes can also detect explosions, including nuclear weapons tests. The People’s Republic of Korea (PRK) conducted six underground nuclear tests between 2006 and 2017. This animation includes these tests as black circles scaled according to their equivalent earthquake magnitudes.
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To see an animation of the 2011 Japan tsunami, please watch:
• Tsunami Forecast Model...
To see how subduction zones make tsunamis, please watch:
• How to Make a Tsunami
To see a comparison of the relative sizes of some historic earthquakes, please watch: • Perspective: a graphic...
To see how seismologists distinguish between earthquakes and explosions, please watch:
• Earthquake or Bomb? Ho...
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Tsunami data from NOAA’s Global Historical Tsunami Database:
www.ngdc.noaa.gov/hazard/tsu_...
Earthquake Data Source: United States Geological Survey (USGS)/National Earthquake Information Center (NEIC) searchable catalog:
earthquake.usgs.gov/earthquak...
Plate boundaries from UTIG’s PLATES project:
ig.utexas.edu/marine-and-tect...