Context: a graphical comparison of earthquake energy release in Hawaiʻi @PacificTWC

PacificTWC | Context: a graphical comparison of earthquake energy release in Hawaiʻi @PacificTWC | Uploaded 6 years ago | Updated 1 hour ago
On May 4, 2018, the largest earthquake in 43 years struck Hawaiʻi with a moment magnitude of 6.9 in the Kalapana region of the Island of Hawaiʻi (the “Big Island”). This animation puts that earthquake in historic context by comparing its magnitude with those of other earthquakes that have struck these islands in the last 150 years.

The moment magnitude number is proportional to an earthquake's total energy release such that each whole number increase in magnitude represents about a 32-fold increase in energy relase. For example, a M7 earthquake releases about 32 times as much energy as a M6 earthquake. Therefore in this animation the circle for a M7 earthquake has about 32 times the area of a M6 earthquake. Each circle is also labeled to show its magnitude, its location, and the year it happened. The animation reveals that three earthquakes are known to have been larger—that is, have released even more energy—than 2018 Kalapana earthquake. The animation concludes with a map showing where each of these earthquakes happened in Hawaiʻi.

Global version:
youtu.be/sTvtKUb-RsY

----------

Earthquake data sources:

USGS/NEIC Searchable Earthquake catalog
earthquake.usgs.gov/earthquakes/search

USGS Professional Paper 1527: Seismicity of the United States, 1568-1989 (revised) by C.W. Stover and J.L. Coffman
pubs.er.usgs.gov/publication/pp1527

Five Years of Earthquakes in Southern Alaska: 2015 - 2019

Earthquakes of Hawaiʻi Island: 2013 - 2018

Tsunami Forecast Model Animation: Sumatra 2004

Tsunami Forecast Model Animation: Chile 1960

Earthquakes of the First 15 Years of the 21st Century

Tsunami Animation: Three Tsunamis From Chile

Perspective: a graphical comparison of earthquake energy release

$40 Years of Earthquakes in the Contiguous United States: 1980 - 2020 Every state and territory of the United State of America experiences earthquakes. In the contiguous states most of these earthquakes do not pose a tsunami risk as they do not lift or drop the seafloor. They are either too small, too far from a body of water, or move the underlying rock sideways. For these reasons two widely-felt earthquakes in March of 2020 also failed to generate tsunamis: the M5.7 Salt Lake City, Utah earthquake and the M6.5 Central Idaho earthquake. To put these two earthquakes in context this animation shows earthquakes in the contiguous United States for the previous forty years. Most earthquakes in the world, including those in the United States, are “interplate” earthquakes that occur at plate tectonic boundaries where large sections of the earth’s crust either grind past each other, pull apart, or slam together. With the exception of the Pacific Coast of southern California, the contiguous United States sits atop the North American Plate. This plate meets the Pacific Plate at the San Andreas Fault such that coastal California south of Mendocino rides atop the Pacific Plate, which moves northward relative to the rest of North America. North of Menocino, however, northern California, Oregon, and Washington State are colliding with the Juan de Fuca Plate (JdF) to produce a subduction zone capable of generating tsunamis with megathrust earthquakes. The last time this region produced a devastating tsunami, however, was 320 years ago. Offshore of the Pacific Northwest many earthquakes also occur along the boundaries between the Juan de Fuca Plate and the Pacific Plate. In the southeastern corner of the animation one more subduction zone also generates earthquakes where the North American Plate meets the Caribbean Plate at the Puerto Rico Trench. Earthquakes can also occur away from these plate boundaries throughout the contiguous United States. These are called “intraplate” earthquakes and they occur along faults within the North American continent. In recent years wastewater injection wells, a byproduct of hydraulic fracturing or “fracking” for hydrocarbon extraction, have also produced earthquakes in Oklahoma, north Texas, and eastern Wyoming. Some significant earthquakes in this 40 year period include: May 18, 1980 eruption of Mt. St. Helens (produced 820 ft. landslide-generated tsunami in Spirit Lake) Nov 8, 1980 M7.2 Northern California May 2, 1983 M6.5 Coalinga, California Oct 28, 1983 M7.3 Borah Peak, Idaho Apr 24, 1984 M6.2 Morgan Hill, California Jul 21, 1986 M6.4 Eastern California Nov 23, 1987 M6.2 California Oct 17, 1989 M6.9 Loma Prieta, California (small tsunami) Aug 17, 1991 M6.2 Honeydew, California Aug 17, 1991 M7.0 Offshore of Oregon Apr 22, 1992 M6.3 Joshua Tree, California April 25, 1992 M7.2 Cape Mendocino, California (small tsunami) Jun 28, 1992 M6.5 Big Bear, California Jun 28, 1992 M7.3 Landers, California Sep 2, 1992 M5.8 St. George, Utah Sep 20, 1993 M6.0 Klamath Falls, Oregon Jan 17, 1994 M6.7 Northridge, California Sep 1, 1994 M7.0 Northern California (small tsunami) Apr 14, 1995 M5.7 Marathon, Texas Oct 16, 1999 M7.1 Hector Mine, California Feb 28, 2001 M6.8 Nisqually, Washington Dec 22, 2003 M6.5 San Simeon, California Jun 15, 2005 M7.2 Offshore Northern California (small tsunami) Sep 10, 2006 M5.8 Gulf of Mexico, Florida Feb 21, 2008 M6.0 Wells, Nevada Apr 4, 2010 M7.2 Baja California (Mexico) Jan 9, 2010 M6.5 Eureka, California Aug 23, 2011 M5.9 Virginia Mar 10, 2014 M6.8 Ferndale, California Aug 24, 2014 M6.0 South Napa, California Sep 3, 2016 M5.8 Oklahoma Dec 8, 2016 M6.6 Ferndale, California Jul 5, 2019 M7.1 Ridgecrest, California Aug 29, 2019 M6.3 Oregon Coast Mar 18, 2020 M5.7 Salt Lake City, Utah Mar 30, 2020 M6.5 Central Idaho The National Tsunami Warning Center (NTWC) has the primary responsibility for issuing alerts for any tsunamis generated near the coastlines of the contiguous United States. NTWC will also alert these areas for dangerous tsunamis generated further away, such as the tsunami from Japan in 2011. Similarly the Pacific Tsunami Warning Center (PTWC) will alert the areas they serve Hawaii, U.S. territories, and international partners for any tsunami threat, including any tsunami generated off the coasts of the continental United States. These alerts will be posted to: https://tsunami.gov Earthquake data from USGS/NEIC database: https://earthquake.usgs.gov/earthquakes/search/ Tsunami data from NOAA/NCEI Tsunami Database: https://www.ngdc.noaa.gov/hazard/tsu_db.shtml Plate boundaries from UTIG’s PLATES project: https://ig.utexas.edu/marine-and-tectonics/plates-project/$