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Geologists have confirmed a strange unprecedented “boomerang” earthquake deep under the Atlantic Ocean

Earthquakes come and go, often leaving destruction behind. What they luckily don’t usually do is turn around immediately and come back for another push. Except … it looks like they can do it on very rare occasions.

In a new study, scientists have uncovered evidence of an unusual and almost unprecedented boomerang earthquake that shook the deep seafloor under the Atlantic Ocean in 2016.

This earthquake, dubbed “reverse super-shear rupture”, occurred along the Romansh fracture. It is an area that lies near the equator, about halfway between the east coast of Brazil and the west coast of Africa.

The rift, which stretches about 900 kilometers between the South American and African tectonic plates, adjacent to the Mid-Atlantic Ridge, caused a 7.1 magnitude earthquake in August 2016, which was detected by underwater seismometers in the region, as well as by remote monitoring stations.

Analysis of the signals reveals that this was not an ordinary earthquake, but a strange earthquake that went one way before turning around and returning and with a significant increase in speed.

“While scientists have found that this reverse rupture mechanism is possible on the basis of theoretical models, our new study provides some of the clearest evidence that this mysterious mechanism actually occurs,” Stephen Hicks said, lead researcher and seismologist of Imperial College London.

According to the analysis of seismic data, the 2016 earthquake had two separate phases.

First, the rip extended upward and eastward towards the weak point where the rip zone meets the Mid-Atlantic Ridge. Then, in a sudden U-turn, an “unusual westward propagation” occurred, with the tremors returning to the center of the fault and at significantly accelerated “super-shear” velocities of up to 6 kilometers per second.

“Even though the structure of the fault appears to be simple, the quake grew differently, and it was completely the opposite of how we expected the quake to look before we started analyzing the data.”

While the team’s explanation for how this boomerang unfolded remains speculative so far, the researchers speculate that the first, deep phase of the quake released enough fracture energy to initiate a reversal of the rift in the shallower, western underwater terrain.

“Either both sections of the fault were preseismically loaded enough to promote seismogenic failure, or the deeper SE1 fracture instantly increased static stress, immediately causing the shallower portion of SE2 to collapse,” the authors explain in their paper.

Although earthquakes propagating in the opposite direction have been studied by seismologists before, so far there has been little evidence of their existence, and this phenomenon is mainly observed in theoretical modeling.

Finding this type in the real world – in the middle of the ocean – is the first of its kind, not to mention the boomerang that returned at super shear speed.

“To my knowledge, this is the first time this has been reported,” geophysicist Yoshihiro Kaneko of GNS Science in New Zealand, who was not part of the research team, told National Geographic.

The results are reported to Nature Geoscience.

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Planet Earth

Climate change kicked off a new Great Migration

If you think that the effects of climate change will not come soon, you will be disappointed. Numerous scientific studies show that global warming will lead to devastating consequences, including the movement of people around the planet on an unprecedented, destabilizing scale. Thus, droughts, floods, bankruptcy and famine are already forcing people to leave their homes. 

The situation is such that environmental hazards affect populations across the planet and – under certain conditions – can stimulate migration. The most important factors are temperature changes, variability in precipitation, and rapid-onset natural disasters such as tropical storms, according to a study by researchers at the Postdam Institute for Climate Impact Research (PIK).

The findings allow researchers to identify geographic regions that may be particularly susceptible to future migration movements. Has the Great Nations Migration really begun?

Migration of peoples

The history of mankind is approximately 2.4 million years old. However, according to a 2015 study, a bone fragment found in Ethiopia in 2013 suggests that humanity is several hundred thousand years older. As the authors of the work, published in the journal Science, write, the genus of primates of the hominid family existed on Earth 2.8 million years ago.

It is important to understand that over the entire period of its existence, human populations have regularly migrated. So, the first to leave Africa and populate Eurasia was Homo erectus (Homo erectus), whose migrations began about 2 million years ago. It was followed by the expansion of Homo sapiens and its close relatives: Neanderthals and Denisovans. A modern man came to the Middle East about 80 thousand years ago.

Today, migration is called any territorial movement of the population associated with the crossing of both external and internal borders in order to change their permanent residence or temporary stay in the territory for study or work, regardless of the factors that contribute to resettlement.

The relentless impact of drought, floods, bankruptcy and famine are forcing people to leave their homes.


Ecological migration is most pronounced in middle-income countries, as well as in countries with developed agriculture. “Environmental factors can stimulate migration, but the magnitude of the impact depends on the specific economic and socio-political conditions in the countries,” writes the lead author of the new study, Roman Hoffmann.

In both low- and high-income countries, the environmental impact on migration is weaker. Presumably because either people are too poor to leave, or in rich countries people have enough financial resources to cope with the consequences. It is in the regions with average incomes and dependence on agriculture that strong waves of population migration are observed.

A large-scale meta-analysis, the results of which are published in the journal Nature Climate Change, revealed a number of interesting patterns. It turned out that the impact on migration depends on the types of environmental hazards and that different hazards can mutually reinforce each other. While temperature changes in the region have the greatest impact on migration, fast-onset natural disasters, changing precipitation variability and anomalies can also play a role.

Brave new world

As the authors of the meta-analysis emphasize, ecological migration always depends on a number of economic and socio-political factors. The story of climate refugees heading for Europe or the US can be oversimplified. For example, researchers have found strong evidence that environmental change in vulnerable countries mainly leads to internal migration or migration to other low- and middle-income countries, rather than cross-border migration to high-income countries. Affected populations often migrate to locations in their own region and eventually return to their homes within a relatively short period of time.

Burgundy marks the regions in which the largest increase in migration is observed; Regions of international population migration are marked in red; Regions of traditional growth of migrants are marked in yellow. 

The results of the study also point to regions that are highly vulnerable to climate change, in which ecological migration may be especially widespread. The authors of the work note that the population of Latin America and the Caribbean, several countries in sub-Saharan Africa, especially in the Sahel region and East Africa, and Western, South and Southeast Asia are particularly at risk.

Given the expected increase in global average temperature, researchers believe that the topic of environmental migration will begin to attract more attention in the future. The best way to protect those affected is to stabilize the global climate, namely to rapidly reduce greenhouse gas emissions from burning fossil fuels. While migration can be an effective adaptation strategy for households, it can be involuntary and accompanied by human suffering. However, the most important conclusion of this meta-analysis, in my opinion, is the fact that forced climatic migrations of large population groups can be avoided.

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Planet Earth

In the Netherlands, people began to be buried in mushroom coffins

This accelerates the decomposition of the body several times.

In the Netherlands, you can continue to help the ecosystem after death by choosing a living mushroom coffin that accelerates the decay of your body. The coffin transforms corpses into compost, which enriches the soil thanks to mycelium.

The idea was coined by Bob Hendrix of the Delft University of Technology. According to him, such a “living cocoon” was the first in the world. 

“This is the world’s first ‘living’ coffin, and last Saturday a deceased person in the Netherlands was composted for the first time and brought back into the cycle of life”

Bob Hendrix

The coffin was the resting place of an 82-year-old woman whose body would decompose within two to three years. The decomposition process in a traditional coffin with lacquered wood and metal handles usually takes over ten years. 

The mushroom coffin itself decomposes within 30-45 days. According to Hendrix, mycelium is the most suitable material for environmentally friendly burial. 

The technology for the production of the coffin includes the collection of moss, the extraction of mycelium from the mushrooms and the addition of wood chips.

The resulting solution hardens in seven days, and then becomes activated again when moisture gets on it. According to Hendrix, this material is a complete organism. 

The bottom of the coffin is covered with moss, which has been added with various soil creatures. This further accelerates the decomposition of the body. 

Hendrix’s startup was named Loop. The scientist has already signed a contract with one of the funeral homes and expects that his work will be a great success. 

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Planet Earth

A tourist fell into a fire trap: published a creepy video from California

The video, which was filmed in the Sierra National Forest, located in California, shows how one of the holidaymakers was in the heart of a fire trap.

This vacationer turned out to be just one person out of 207 who were also captured in the fire and were saved in the very last moments. The rescue service came to their aid, which took people to a safe place. 

In the video, which was made by a man on the estate of Jeremy Remington, you can clearly see how cars burn, and the flame is getting closer to tourists and its speed is noticeably increasing.

People were in a real trap. Fire surrounded them on all sides, and the roads that could be driven were destroyed. According to the information provided by the Emergency Situations Department, work to rescue tourists began on Saturday evening and continued until Sunday morning. 

More than 20 people had to be transported to hospitals. Two of the victims were in critical condition and required immediate medical attention. At the same time, two people who were vacationing in the National Forest refused the proposed evacuation.

The scale of the wildfire that started on Friday is not too large. But at the same time, the fire managed to destroy more than 71 square miles of forest. By the middle of Saturday, due to the increase in the rate of spread of fire, a 7 times larger area was destroyed. 

On Sunday morning, it was possible to stop the fire by no more than 5%, so the work continued actively and further.

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