Related Research Articles
Earthquakes are caused by movements within the Earth's crust and uppermost mantle. They range from events too weak to be detectable except by sensitive instrumentation, to sudden and violent events lasting many minutes which have caused some of the greatest disasters in human history. Below, earthquakes are listed by period, region or country, year, magnitude, cost, fatalities and number of scientific studies.
The 1918 San Fermín earthquake, also known as the Puerto Rico earthquake of 1918, struck the island of Puerto Rico at 10:14:42 local time on October 11. The earthquake measured 7.1 on the moment magnitude scale and IX (Violent) on the Mercalli intensity scale. The mainshock epicenter occurred off the northwestern coast of the island, somewhere along the Puerto Rico Trench.
The 1982 Flores earthquake struck the island of Flores in Indonesia on December 25. Registering a moment magnitude of 5.9, according to the International Seismological Centre, it created landslides and was reportedly accompanied by a tsunami. The earthquake killed thirteen people and left 390 injured, also destroying 1,875 houses and 121 other buildings. The villages of Layahong and Oyong Barang were damaged by seven seconds of shaking.
The 1975 Hawaii earthquake occurred on November 29 with a moment magnitude of 7.7 and a maximum Mercalli intensity of VIII (Severe). The shock affected several of the Hawaiian Islands and resulted in the deaths of two people and up to 28 injured. Significant damage occurred in the southern part of the Big Island totalling $4–4.1 million, and it also triggered a small brief eruption of Kilauea volcano.
The 2014 Aleutian Islands earthquake occurred on 23 June at 11:53 HDT (UTC-9) with a moment magnitude of 7.9 and a maximum Mercalli intensity of VIII (Severe). The shock occurred in the Aleutian Islands – part of the US state of Alaska – 19 miles (31 km) southeast of Little Sitkin Island.
The 1993 Guam earthquake occurred on August 8 at 6:34:26 pm local time with a moment magnitude of 7.8 and a maximum Mercalli intensity of IX (Violent). The thrust earthquake generated a non-destructive tsunami.
The 2021 Kermadec Islands earthquakes were a series of earthquakes with magnitudes of 8.1 and 7.4 that occurred at 19:28:31 UTC on 4 March 2021. The epicentres were located southeast of Raoul Island in the Kermadec Islands, part of the New Zealand outlying islands. The main magnitude 8.1 earthquake was preceded by a magnitude 7.4 foreshock and followed by a magnitude 6.1 aftershock. A separate, unrelated magnitude 7.3 earthquake occurred off the coast of the North Island of New Zealand, approximately 900 km to the south, several hours before the main quakes. More than a dozen aftershocks exceeded magnitude 6.
The 2021 South Sandwich Islands earthquakes were a pair of powerful earthquakes, followed by many strong aftershocks which struck along the South Sandwich Trench in August 2021. The quakes measured 7.5 and 8.1 on the moment magnitude scale, according to the United States Geological Survey. The mainshock is tied with another event in 1929 as the largest earthquake ever recorded in this region and the Atlantic Ocean as a whole, and is tied with the 2021 Kermadec Islands earthquake as the second largest earthquake of 2021.
References
Sources
- NGDC (1972), Significant Earthquake Database (Data Set), National Geophysical Data Center, NOAA, doi:10.7289/V5TD9V7K