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Mapped: The World’s Major Earthquakes from 1956‒2022

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This map highlights the epicenters of earthquakes on record between 1956 and 2022.

Mapping The World’s Major Earthquakes from 1956‒2022

Major earthquakes have occurred since time immemorial, but their observation and impact have not been evenly distributed around the globe.

On February 6, two earthquakes struck in Türkiye near the Syrian border. Both registered above a 7 on the Richter scale and have a combined death toll rapidly rising past 20,000 people.

And looking at the history of recent and ancient earthquakes, the location of these is no surprise. Using data from the United States Geological Survey (USGS), creator PythonMaps mapped earthquake epicenters between 1956 and 2022 that registered a 4.5 or higher on the Richter scale.

Tectonic Plate Movement and Earthquakes

Looking at the map, it’s easy to spot the concentration of earthquakes along the boundaries of Earth’s tectonic plates.

These massive moving slabs of rock fit together almost like puzzle pieces, making up the lithosphere or the upper crust. But as the edges of tectonic plates collide, slide against, and move away from each other, the crust cracks and folds and causes earthquakes.

Most of the earthquakes visualized on this map follow the boundaries of the seven major tectonic plates, along with the Philippine Plate (south of Japan) and the Nazca Plate (west of South America).

Here’s a list of the most earthquake-prone areas on the planet, according to the USGS.

Earthquake ZonesTectonic PlatesLocations
Ring of FirePacific, North American, Philippine, Juan de Fuca, Cocos, NazcaRim of the Pacific Ocean.
Alpide BeltEurasian, African, Arabian, IndianJava to Sumatra, through the Himalayas, west to the Mediterranean, and out into the Atlantic.
Mid-Atlantic RidgeNorth American, Eurasian, South American, AfricanDeep underwater in the Atlantic, and directly underneath Iceland.

According to academics, the recent earthquakes in Türkiye (part of the Alpide Belt) happened on multiple faults. The Arabian Plate likely moved northwards into the Eurasian Plate, pushing the Anatolian Plate (which Türkiye sits on) westward.

The Worst Earthquakes in History

Though earthquakes are spread around the world, major earthquakes seem even more tightly confined to specific regions.

These major earthquakes register highly on magnitude scales, such as the Richter scale (ML) and the newer and more commonly-used moment magnitude scale (Mw). These scales are logarithmic and ramp up quickly, so for the Richter scale, each whole number increase roughly corresponds to a 31.6-fold increase in energy released.

The map above sees a concentration of these bigger magnitude earthquakes congregating heavily around both sides of the Pacific Ocean. This border is also known colloquially as the “Ring of Fire” for its persistent volcanic activity, also caused by tectonic plate movement.

But the red points representing major earthquakes registering 9+ on the Richter scale are far and few between. Here’s a list of the 20 worst earthquakes in history, based on magnitude.

RankNameMagnitudeLocationDate (Y-M-D)
1Valdivia Earthquake9.5Bio-Bio, Chile1960-05-22
2Good Friday Earthquake9.2Alaska, U.S.1964-03-28
32004 Indian Ocean Earthquake9.1Sumatra, Indonesia2004-12-26
4Tohoku Earthquake9.1Honshu, Japan2011-03-11
51952 Severo-Kurilsk Earthquake9.0Kamchatka, Russia1952-11-04
6Maule Earthquake8.8Bio-Bio, Chile2010-02-27
71906 Ecuador–Colombia Earthquake8.8Ecuador1906-01-31
8Rat Islands Earthquake8.7Alaska, U.S.1965-02-04
9Assam-Tibet Earthquake8.6Assam, Tibet1950-08-15
102012 Indian Ocean Earthquake8.6Sumatra, Indonesia2012-04-11
11Nias Earthquake8.6Sumatra, Indonesia2005-03-28
121957 Andreanof Islands Earthquake8.6Alaska, U.S.1957-03-09
13Unimak Island Earthquake, Alaska8.6Alaska, U.S.1946-04-01
141938 Banda Sea Earthquake8.5Banda Sea1938-02-01
151922 Vallenar Earthquake8.5Chile-Argentina Border1922-11-11
161963 Kuril Islands Earthquake8.5Kuril Islands, Russia1963-10-13
171923 Kamchatka Earthquake8.4Kamchatka, Russia1923-02-03
18September 2007 Sumatra Earthquakes8.4Sumatra, Indonesia2007-09-12
19Peru Earthquake8.4Southern Peru2001-06-23
201933 Sanriku Earthquake8.4Honshu, Japan1933-03-02

Areas near Indonesia, Russia, and Chile — all on tectonic plate boundaries — have seen half of the largest earthquakes recorded in history.

That said, there could have been earlier and larger earthquakes not recorded. Earlier civilizations lacked precise instruments to measure and document them and preserved written observations only, with some of the earliest records dating back nearly three millennia.

Can We Predict Major Earthquakes?

Despite the ability to measure both location and intensity of earthquakes (using a seismograph), scientists still cannot precisely predict exactly where, when, or at what magnitude an earthquake will occur.

However, they can measure the probability of an earthquake occurring, especially around fault zones. A famous example is “the big one” around the Cascadia subduction zone in North America which occurs every 200 to 800 years.

In areas that sit on fault lines between plates, earthquake preparedness can play a big role in mitigating risk.

Interested in tectonic plate shifts? Here’s an animated video which shows one billion years of tectonic plate movement in 40 seconds.
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This article was published as a part of Visual Capitalist's Creator Program, which features data-driven visuals from some of our favorite Creators around the world.

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Misc

Ranked: Biotoxins in Nature, by Lethal Dose

The world can be a poisonous place. We look at a number of different biotoxins found in the natural world and rank their toxicity.

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Visually Ranking Biotoxicity Shareable

Biotoxins: Poisons of the Natural World

Biotoxins are harmful substances that come from living organisms.

They can take many forms, from the venom of a snake or spider to the neurotoxins produced by certain types of algae or microbes.

In the infographic above, we look at some common biotoxins in the natural world and rank them based on how deadly they are to an average 70 kg (154 lb) human being.

Ranking Biotoxins on a Toxic Scale

A basic concept in toxicology is that “only the dose makes the poison”. Everyday harmless substances like water have the potential to be lethal when consumed in large enough concentrations. Measuring a lethal dosage is very difficult.

First, living things are complex: factors like size, diet, biochemistry, and genetics vary across species. This makes it difficult to qualify toxicity in a universal way.

Second, individual factors like age or sex can also affect how deadly a substance is. This is why children have different doses for medications than adults.

Third, how a poison is taken into the body (orally, intravenously, dermally, etc.) can also impact its deadliness.

As a result, there are many ways to measure and rank toxicity, depending on what substance or organism is under investigation. Median lethal dose (LD50) is one common way for measuring toxicity. LD50 is the dose of a substance that kills 50% of a test population of animals. It is commonly reported as mass of substance per unit of body weight (mg/kg or g/kg). In the graphic above, we curate LD50 data of some select biotoxins found in nature and present them on a scale of logarithmic LD50 values.

What’s surprising is just how potent some toxins can be.

Bits and Bites about Biotoxins

While one would think that biotoxins are avoided at all costs by humans, the reality is more complicated. Here are some interesting facts about biotoxins present in nature, and our unusual relationships with the organisms that create them:

1. Fungi and molds make poisons called mycotoxins
Mycotoxins are a global problem. They affect crops from many countries, and can cause significant economic losses for farmers and food producers.

2. Phytotoxins can defend plants…and attack cancer
Plants use phytotoxins to defend themselves other organisms, like humans. Urushiol, for example, is the main toxic component in the leaves of poison ivy, poison oak, and sumac. But the Pacific yew tree produces taxol that’s valuable in chemotherapy treatments.

3. Fire salamander toxin is an ingredient in Slovenian whisky
Though not widely available, some whisky makers in Slovenia use samandarine from the fire salamander to create a psychedelic alcohol.

4. Ciguatoxins exist in the guts of reef fish
Very unique species of bacteria living in the digestive tract of reef fishes make ciguatoxin. They transmit this poison to other organisms when the host fish is eaten.

5. Pufferfish are deadly, but also delicious
Pufferfish contain tetrodotoxin, a potent neurotoxin in their ovaries, liver, and skin called tetrodotoxin. Despite being a delicacy in many countries around the world, it has a lot of strict regulations because of its ability to kill people. In Japan, for example, only specially licensed chefs can prepare pufferfish for consumption.

6. Batrachotoxin is lethal to the touch
The skin of some poison dart frogs secretes a deadly substance called batrachotoxin. It is so potent that simply touching the poison can be fatal. Indigenous people of Central and South America used batrachotoxin to poison the tips of hunting weapons for centuries.

7. Botox contains the most deadly biotoxin known
Commercial botox uses an extremely small amount of biotoxin from a microbe called Clostridium botulinum. It paralyzes the muscles, preventing contraction (i.e. wrinkling). It is the deadliest known biotoxin on Earth. One gram of botulinum toxin can kill up to one million people.

Caveats of Measuring and Reporting Biotoxicity

While we use LD50 data to rank biotoxicity, it isn’t an exact science. There is room for improvement.

For starters, no LD50 data exists for humans. That means data from other organisms has to be converted to apply to humans. There is a lot of contention amongst scientific communities about how accurate this is.

There has also been an increasing effort to move to new methods of measuring toxicity that are not harmful to animals. Several countries, including the UK, have taken steps to ban the oral LD50, and the Organisation for Economic Co-operation and Development (OECD) abolished the requirement for the oral test in 2001.

Now, new ways of evaluating toxicity are under investigation, like cell-based screening methods.

Correction: Water was mislabeled on a previous version of the infographic. Full sources here

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