When your world is literally shaking, don’t panic, it’s just a tremor. A tremor is the result of energy being released from the Earth’s lithosphere, that causes seismic waves. You need to know what to do to keep yourself safe when an earthquake strikes. But, you should also know these unbelievable and surprising things about earthquakes. Read on to learn 50 facts about the earthquakes.
Fact 1: An earthquake can physically move a place from its fixed coordinate.
- On February 27th 2010, an intense 8.8 scaled earthquake moved the city of Concepcion, in Chile, 10 feet to the West from its original location.
- That same earthquake, also slightly altered the rotation of the planet making the day shorter.
Fact 2: The deadliest earthquake in history killed more than 830,000 people.
- It happened in Shansi, China on January 23, 1556.
- Most deaths were caused by mass destruction, and people being buried under fallen structures.
Fact 3: In the past 4,000 years, earthquakes have claimed the lives of an estimated 13 million people.
- Earthquakes kill around 8,000 people per year.
- The number is gradually decreasing per year, due to better preparations and stronger buildings in some countries.
Fact 4: An earthquake in the Indian Ocean in 2004, generated enough electricity to power the whole of the United States for 3 days.
- It was so powerful that it even affected the San Andreas Fault, effectively weakening it.
- Its energy is comparable to 26,000 hiroshima bombs. Just google the photo of hiroshima after it was bombed during the Second World War, and try to imagine that being 26,000 times worse.
Fact 5: In Japanese Mythology, there is a creature believed to be responsible for earthquakes, it’s called Namazu.
- amazu or Onamazu, is a giant catfish that is believed to live under the islands of Japan.
- Namazu is being restrained by the god Kashima, using stones. But when Kashima lets his guard down, the catfish roams around causing violent earthquakes.
Fact 6: Aftershocks are “small earthquakes” caused by the ground re-adjusting itself, after the main earthquake has taken place.
- It usually happens minutes after the earthquake, around 2-3 times, but is significantly weaker.
- There are aftershocks, especially those from huge earthquakes, that last for a year.
Fact 7: The “Earthquake Capital of the World” is found in the United States.
- It is located in Parkfield, California, where the San Andreas Fault runs through its centre.
- There is actually a bridge in that area connecting two tectonic plates.
Fact 8: Geological faults are the reason for 95% of the earthquakes.
- There are other reasons why the ground shakes like volcanic eruptions and landslides.
- Humans can cause earthquakes too, especially during nuclear and mine tests.
Fact 9: The “epicentre” is not the origin of the earthquake.
- It is the point directly above the ‘hypocenter’ of the earthquake, at ground level.
- The origin of the earthquake is called, “focus” or “hypocenter.”
Fact 10: Ancient Greeks believed that it was Poseidon who caused earthquakes.
- It was believed that when he was angry, he would strike the ground with his powerful trident causing the earth to shake.
- Because of his violent nature, he gained the monicker “Earth-Shaker.”
Fact 11: According to the Hindus, the Earth is being held by 8 elephants.
- These elephants stand on top of a turtle, that stands on top of a snake.
- Any movement caused by these animals causes an earthquake.
Fact 12: A tsunami is commonly triggered by an Earthquake.
- It travels as fast as a jet, reaching a maximum speed of 970 kilometres per hour.
- Once the tsunami reaches the shoreline, it reaches its peak height of around 30 meters and crashes into whatever is before it.
Fact 13: There was a tsunami that reached 85 meters high.
- It happened in Japan in 1771, causing massive damage in Ishigaki Island
- It was called the Great Yaeyama Tsunami, around 8,500 people died.
Fact 14: A pagoda’s design is meant to withstand an earthquake.
- Pagodas in the East have a central pillar that acts as a spine. This can bend to absorb strong external forces caused by earthquakes or strong winds.
- In Japan, there are only 2 known pagodas that have collapsed in the last 1400 years, because of an earthquake.
Fact 15: If an earthquake registered less than 3.0 magnitude, it’s almost imperceptible.
- Only animals can detect such movement and it’s mainly those that are underground.
- An earthquake has to register above 7.0 magnitude before it can be considered as a major earthquake.
Fact 16: San Francisco burned for 3 days and 3 nights because of an Earthquake.
- An earthquake in 1906, in California, brought about massive destruction, especially to the San Francisco area.
- The earthquake was recorded as 7.8 in magnitude, enough power to destroy gas lines and cause massive fires.
Fact 17: There was an earthquake detector as early as 2000 years ago.
- It was invented by a Chinese Astronomer named Zhang Heng, and was believed to be the first device to detect earthquakes.
- It could read an earthquake signal where the epicenter was 600 kilometres away.
Fact 18: 80% of the major earthquakes in the world happen in the Pacific Ring of Fire.
- This is a horse-shoe shaped area in the Pacific Ocean, where major tectonic plates meet.
- In this area there are several active volcanoes, thus the name of the area.
Fact 19: Earthquakes actually only occur in the crust of the Earth.
- Since tectonic plates float around in the Earth’s mantle, their movements set off earthquakes.
- The most devastating ones are those that have a shallow origin, but are strong enough to trigger massive land movements.
Fact 20: The seismograph, the device used to detect earthquakes, was invented in 1880 by John Milne.
- It detected earthquakes through a long pendulum attached to a stylus. This stylus drew out a pattern onto paper, which demonstrated the direction and strength of the earthquake.
- The development of electromagnetic seismograph in the 20th century, allowed scientists to detect even the slightest movement in the ground, that is otherwise unfelt by humans.
Fact 21: The Richter Scale, the measurement we used to determine how strong an earthquake is, was introduced by American scientist Charles Richter.
- It is based on a ‘base-10 logarithmic scale’.
- The number read on the scale is always 10x stronger than the previous number. For example, a 6.0 magnitude reading on the Richter Scale, is 10x stronger than a 5.0 reading.
Fact 22: There is on average, 2 earthquakes per day, that we don’t notice at all.
- It amounts to almost 1.3 million earthquakes per year.
- Its magnitude is 2.9 or lower. It’s only recorded on seismograph but people won’t be able to notice it.
Fact 23: The energy released during an earthquake is so destructive, it can theoretically destroy an entire country.
- Its energy can amount to 100 times more than the energy released by a nuclear bomb.
- Different energies can be released by an earthquake such as seismic waves, heat energy, and gravitational potential energy.
Fact 24: If you are near a pond and you suddenly smell something weird, an earthquake is coming.
- It has been recorded that before an earthquake, ponds and canals give off a strange smell.
- This is because gases are released underground due to the movement of land, before an earthquake.
Fact 25: There are also “earthquakes” on the moon.
- Since they’re happening on the moon, they are actually called “moonquakes.”
- Based on the data recorded, most of these moonquakes are generally weaker than the “earthquakes.”
Fact 26: A 20 second earthquake can be so destructive, it can destroy an entire town.
- In 1995, the Kobe town in Japan was hit by a relatively normal earthquake that lasted for about 20 seconds.
- It was enough to destroy 100,000 buildings, and killed around 5,000 people. 300,000 were also left homeless.
Fact 27: Your distance from the epicentre does not matter, if your location is connected to the same tectonic plates that caused the earthquake.
- An earthquake in Alaska caused flooding on the coast of Hawaii, even though there’s around 3,100 miles distance between them.
- An earthquake in Portugal in 1775, caused some waves on Loch Ness in Scotland, despite the 1,240 mile distance.
Fact 28: The San Andres Fault in California is moving about 2 inches per year.
- To give you some context, this is the same rate a human fingernail grows.
- In theory, if this rate continues, the cities of Los Angeles and San Francisco will be next to each other in 15 million years.
Fact 29: The San Andreas Fault is considered as one of the longest fault zones in the world, as it consists of many tiny faults.
- It runs over 800 miles. Starting from San Francisco, running through Southern California and up to Mexico.
- It is named after the body of water that formed in the valley, between the 2 tectonic plates.
Fact 30: Japan is one of the countries with most recorded number of earthquakes.
- There are thousands of earthquakes happening in Japan, but most of them are very weak.
- That’s why the whole nation is equipped with earthquake protection in some form, in case they are hit with a strong earthquake.
Fact 31: The worst earthquake that happened in Japan on March 11th, 2011.
- It recorded a 9.0 magnitude, which created a tsunami 10 meters high.
- It also severely damaged nuclear power plants in the country.
Fact 32: The 2011 Earthquake in Japan altered their geographical location.
- It moved the country a few centimetres closer to the United States.
- Also, it was so strong that it shifted our planet’s axis by 6.5 inches. It shortened the day by a little bit more than 1 microsecond.
Fact 33: An average earthquake lasts for around a minute.
- This average time includes the beginning of the earthquake (shaking) and the ground re-adjusting.
- The longest earthquake on record lasted for around 10 minutes. It happened in the Indian Ocean in 2004.
Fact 34: There are more earthquakes happening in the Northern Hemisphere compared to the Southern Hemisphere.
- It’s because there are more faults located in the North than in the South.
- There are also more active volcanoes found in the North.
Fact 35: The worst avalanche caused by an earthquake happened in Peru in 1970.
- It contained an 800-meter wave of mud, ice, and rocks falling down from the mountain in Huascaran. This all happened at a speed of 400 kilometre per hour.
- It killed more than 18,000 people and buried an entire village.
Fact 36: There are four types of geological faults.
- 1. Normal and 2. Reverse
- 3. Thrust and 4. Strike-up
Fact 37: The 260-meter high Transamerica Pyramid, located in San Francisco, can withstand strong earthquakes.
- With 48 floors, it was the tallest skyscraper in San Francisco until 2018 and was considered as one of San Francisco’s icons.
- It is no longer the headquarters of Transamerica but it is still connected to the company.
Fact 38: Although volcanic eruptions can cause earthquakes, the reverse can happen too!
- Sudden ground movement can release gas and lava from active volcanoes, causing an eruption.
- This happened in Mount St. Helens in 1980, and in Mount Etna in 2002.
Fact 39: Scientists theorize that animals have the ability to detect an earthquake before it happens.
- One theory is, animals have the ability to sense electrical signals sent by the movements underground.
- Another theory within some tribes is, if the animals are acting out and are trying to escape, it means that there’s an incoming disaster.
Fact 40: Alaska has the most number of earthquakes in the United States.
- In the last 100 years, it was hit by at least 5 great earthquakes registering above 7 in magnitude.
- It also recorded the strongest earthquake that happened in the country. It was hit by a 9.2 magnitude earthquake in 1964.
Fact 41: The damage caused by the earthquake depends on the depth of the origin and the fault type.
- The more shallow the origin is, the stronger the earthquake is.
- Deep earthquakes might lose their seismic wave energy along the way, but they are sometimes widely felt.
Fact 42: Japan, as an earthquake-prone country, built modern buildings and houses that could withstand earthquake issues.
- After a huge earthquake in 1995, the country invested heavily in monitoring earthquakes and also in strengthening buildings.
- Their expertise in engineering has been recognized internationally. By using their strategies the number of casualties during earthquakes has reduced internationally.
Fact 43: When Haiti was hit by a devastating earthquake in 2010, the world united to help the country stand once again.
- The 7.0 magnitude earthquake in Haiti killed over 200,000 people and destroyed millions of properties.
- Many countries responded and sent support, funds, medical teams, engineers, and other professionals to help rebuild the country.
Fact 44: An earthquake’s damage is further intensified by a tsunamis damage.
- In 2011, the tsunami, triggered by the earthquake in Japan, was powerful enough to destroy several coastal communities. This added even more casualties to the already destructive earthquake’s damages.
- In 2004, the tsunami generated by an earthquake in the Indian, ocean killed 200,000 people in 14 different countries.
Fact 45: New Zealand was hit with 2 earthquakes in 6 months, this greatly affected its economy.
- The second earthquake reached 7.1 magnitude and damaged the central city of Christchurch, New Zealand.
- It was estimated that the damage reached up to 15 billion NZ$.
Fact 46: The sun and the moon can cause earthquakes too.
- It has been established that the gravitational push and pull of the Sun and the Moon cause tides.
- However, it was recently established that the forces created by the tug of Sun and Moon, stimulates ground movement in the San Andreas Fault.
Fact 47: Weather does not affect the frequency of earthquakes.
- There has been no evidence that suggests changes in the weather can also affect earthquakes.
- In fact, statistically there’s an equal distribution of the number of earthquakes in different weathers.
Fact 48: The circumference of the Earth was trimmed by the 2004 Indonesian earthquake.
- This deadly earthquake shook the international community, because of the number of people who died and the extent of damage in communities.
- Also, the catastrophic displacement of land areas reduced the bulge of the planet, making it rounder.
Fact 49: Do not believe anyone who says March is an earthquake month.
- This idea was established because 2 of the biggest earthquakes occurred in the month of March.
- However, the next 3 big earthquakes happened in different months completely debunking this assertion.
Fact 50: Earth is expected to have 1 ‘Mega’ earthquake every year.
- The number of earthquakes per year has remained constant for the past century.
- It was predicted that at least 17 major earthquakes, with a magnitude of 7.0 to 7.9, would happen per year. Plus 1 ‘mega’ earthquake with a magnitude of 8.0 and above.