Earth can be visualized as a chaotic mass of rocky tectonic plates floating on a sea of molten metal. These plates are constantly moving and rubbing against each other, releasing massive amounts of energy that result in earthquakes. So, what is the largest earthquake ever recorded?
It is estimated that around 20,000 earthquakes occur worldwide each year, averaging about 55 earthquakes per day. Of these, approximately 16 are categorized as major (magnitude 7 or higher) annually.
Most earthquakes take place under the sea, posing a significant threat due to the potential of triggering massive tsunamis upon hitting the land after an undersea earthquake.
The Richter scale was introduced in the 1930s to standardize earthquake magnitude measurements, making it easier to compare sizes. However, the scale had its limitations. Since then, the moment magnitude (Mw) scale has been used to rank the top 10 earthquakes.
Similar to the Richter scale, the moment magnitude scale is logarithmic, meaning that with each integer increase on the scale, the earthquake becomes 10 times more powerful. For instance, a 9 Mw earthquake is 6 magnitude levels stronger than a 1,000Mw earthquake.
Here are the top 10 largest earthquakes ever recorded:
10 – Indian Ocean, 2012
The Aceh province of Indonesia, known for seismic activity, experienced a massive 8.6 Mw earthquake on April 11, 2012. The earthquake, which occurred 610km off the coast of Banda Aceh, was followed quickly by an 8.2 Mw earthquake. While the earthquakes caused mass panic and coastal evacuations, physical damage was minimal, and the feared tsunami did not materialize.
This seismic event was the largest instance of a sideslip earthquake in recorded history, characterized by horizontal movement of the crust along two plates rather than vertical motion. Such earthquakes are less likely to trigger significant tsunamis compared to vertical strike-slip faults.
9 – Aleutian Islands, USA, 1946
In the North Pacific Ocean, the Aleutian Islands experienced an 8.6 Mw earthquake in April 1946, triggering a widespread tsunami that caused extensive damage. This tsunami, traveling at 800km/h, reached the Hawaiian Islands in just five hours, resulting in 159 deaths and significant destruction.
Due to the earthquake’s magnitude and location, the wave height on Unimak Island, near the epicenter, reached 42 meters. The earthquake also generated a tsunami in Antarctica, over 15,500 km away.
8 – Assam, India, 1950
The most powerful earthquake ever recorded on land struck between India’s Assam state and Tibet in 1950. This earthquake, measuring 8.6 Mw, resulted from the collision of the Indian and Eurasian tectonic plates.
The earthquake triggered massive landslides in Tibet, causing entire villages to slide into the river and be swept away. In India, 70 villages were destroyed due to landslides and natural dam collapses, resulting in an estimated 4,800 fatalities.
The tragedy claimed around 1,500 lives in India and 3,300 in Tibet.
7 – Mouse Island, USA, 1965
The Rat Islands, part of the volcanic Aleutian Islands chain, experienced an earthquake in 1965 that triggered a tsunami over 10 meters high on Siemia Island, 304 kilometers away. Remarkably, the resulting tsunami still reached Hawaii, 4,200 km away, generating 1-meter waves despite its remote epicenter.
Fortunately, the damages and casualties were limited due to the sparse population in the affected areas.
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6 – Chile, 2010
On February 27, 2010, a powerful 8.8 Mw earthquake struck the coast of central Chile, near Concepción. Lasting around three minutes, the quake’s impact was felt as far as Sao Paulo, Brazil, 4,620 kilometers away.
The city of Concepción, known for its earthquake history, endured severe damage. In 1939, 1953, and 1960, previous earthquakes caused significant destruction and loss of lives. The 2010 earthquake resulted in tsunami warnings being issued to 53 countries due to its large magnitude and ocean floor rupture.
5 – Severoklisk, Russia, 1952
In 1952, Severokilsk, a volcanic archipelago in Russia’s Kuril Islands located 1,300 km northeast of Japan, experienced a massive earthquake. This earthquake triggered an 18-meter high tsunami that devastated the region, claiming nearly half of the small town’s population.
Residents, forewarned by the earthquake, sought safety on higher ground but returned after the initial wave passed. Tragically, a second wave struck as people returned home, resulting in numerous casualties.
The town was subsequently rebuilt on higher ground following the catastrophe. To date, this remains the largest earthquake documented in Russia.
4 – Tohoku, Japan, 2011
On March 11, 2011, Japan witnessed the largest earthquake ever recorded in the country near Tohoku. The earthquake, with a magnitude of 9.0, had its epicenter about 72 kilometers off the northeast coast of Honshu, resulting in significant movement of the Earth’s axis and land shift.
The ensuing tsunami, a devastating consequence of the earthquake, swept away entire communities and breached previously established defenses. Tsunami waves exceeding 40 meters hit certain coastal areas, overwhelming earlier sea wall predictions.
Additionally, the earthquake triggered a nuclear disaster at the Fukushima Daiichi Nuclear Power Plant due to infrastructure damages caused by the tsunami. The resulting meltdown led to the release of nuclear material into the atmosphere.
The earthquake claimed over 22,000 lives, underscoring its catastrophic impact.
3 – Sumatra, Indonesia, 2004
An enormous 9.1 Mw earthquake, affecting a 1,300km stretch of the Sumatra trench, rocked the region on December 26, 2004. This subduction earthquake occurred over centuries as the Burmese microplate slid under the Indian plate, unleashing massive destruction and spawning a devastating tsunami.
Rising more than 20 meters, the ocean floor shift generated a tsunami exceeding 30 meters in height. The deadly waves swept through coastal areas in 14 nations, resulting in an estimated 228,000 fatalities, with Indonesia, Sri Lanka, India, and Thailand bearing the brunt of the disaster.
This is the most potent earthquake ever documented in Asia and a defining natural calamity of the 21st century.
2 – Alaska, USA, 1964
Alaska, USA, experienced a powerful earthquake in 1964, rupturing 1,000 km of the Pacific and North American plates at once. Lasting nearly five minutes, the earthquake impacted vast areas of North America, with Anchorage suffering severe damage due to inadequate earthquake-proof structures and infrastructure.
The earthquake, the second-strongest recorded in history, significantly influenced North American geology.
1 – Valdivia, Chile, 1960
In 1960, the most massive earthquake on record struck near Valdivia, Chile, with a magnitude of 9.5. This event, one of the deadliest earthquakes in history, resulted in around 5,700 deaths.
Occurring around 3:00 PM local time, the earthquake lasted approximately 10 minutes, causing considerable land subsidence along Chile’s coast, landslides, and road blockages.
Moreover, the tsunami triggered by the earthquake caused extensive coastal devastation.
Chileans had been forewarned by a series of powerful foreshocks, enabling them to prepare for the impending disaster, likely contributing to the relatively fewer casualties.
| position | date | Magnitude (Mw) | |
| 1 | Valdivia, Chile | May 22, 1960 | 9.5 |
| 2 | Alaska, USA | March 27, 1964 | 9.2 |
| 3 | Sumatra | December 26, 2004 | 9.1～9.3 |
| Four | Tohoku | March 11, 2011 | 9.1 |
| Five | kamchatka oblast, russia | November 5, 1952 | 9.0 |
| 6 | Chile | February 27, 2010 | 8.8 |
| 7 | rat island | February 3, 1965 | 8.7 |
| 8 | Assam Tibet | August 15, 1950 | 8.6 |
| 9 | Aleutian Islands | April 1, 1946 | 8.6 |
| Ten | Indian Ocean | April 11, 2012 | 8.6 |
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Source: www.sciencefocus.com
