The first “Big One” earthquake in more than a decade has rattled the world. What if it had happened anywhere else? Say, California? Or Japan?

And does it make this more likely?

On July 29, the remote and sparsely populated Kamchatka Peninsula in the Russian Far East was rocked by a titanic seismic shift measuring 8.8 on the Richter scale.

It was among the 10 strongest ever recorded and it went on for more than four minutes.

The ground leapt. Shuddered. Warped.

Anywhere else, and it most likely would have been a catastrophe.

But damage and injury were minimal. That’s because Kamchatka’s 270,000 sq km’s is inhabited by just 330,000 people.

Sirens Blare in Honolulu as Tsunami Warning Issued

Sirens blared in Honolulu on...more

Sensors positioned around the globe detected it within minutes. Alarm bells have been ringing ever since.

Is it a sign of things to come?

Japan is urgently upgrading its earthquake defences.

An unprecedented swarm has rattled the Tokara Archipelago just south of the Home Islands. It’s endured an unprecedented 1700 tremors in just six months. Authorities warn it may indicate an impending “megaquake”.

A massive 8.7 magnitude earthquake rocks Russia’s Kamchatka Peninsula triggering 4m high tsunami waves. Picture: X @SaffronSunanda

The quake was devastating. Picture: X/@SaffronSunanda

The Philippines is panicking.

Almost a hundred people have been killed. Extensive damage has been done to homes, roads and public services. The fear of a “Big One” has caused populations to panic.

Meanwhile, California is on edge.

Volcanic eruption Flat Tolbachik on the Kamchatka Peninsula. Picture: iStock

Researchers have discovered the infamous San Andreas Fault has an unexpected trigger point.

That’s bad news for a state that suffered 3000 deaths and 80 per cent of the city of San Francisco was levelled on April 18, 1906.

They’re all connected.

They’re all part of the enormous Ring of Fire that circles the entire Pacific and a shudder in one place could lead to an unwelcome shock in another.

The sheer intensity and energy exploding from the 8.7 magnitude earthquake in Russia. Picture: X/@GEZUPA

The San Andreas Fault Line juts out of the flat desert floor in the Coachella Valley, California. Picture: iStock

Shock and awe

Earthquakes are fearsome. But they’re also fascinating.

They’re the ultimate expression of nature’s awesome power and they’re the focus of the world’s ingenuity. After all, unlike storms, tides and solar eclipses, they’re something we still cannot predict.

Understanding remains elusive.

But technological strides now mean scientists are building a greater appreciation of what’s going on under our feet and they hope to soon crack the code of tremors, shakes, sighs and shifts that could point to impending disaster.

This frame grab from UGC video footage taken and posted by Khon Su Cheevit Adeet Mai Suay Rok Na on Facebook on March 28, 2025 shows workers running away from a building as it collapses at a construction site in Bangkok, following an earthquake in Myanmar. Picture: Facebook user Khon Su Cheevit Adeet Mai Suay Rok Na/AFP

They need to hurry.

The world is getting crowded.

A century ago, Japan had a population of about 60 million. Now it’s 124 million.

In 1925, the Philippines was home to 12 million people. Now it’s 117 million.

California has leapt from 4.7 million to 39.5 million.

That means far more people in far more places are exposed to severe seismic events.

Nobody died in Russia’s July 29 Kamchatka quake.

View of the waves in Vina del Mar, Chile. Chile was warned on July 29, 2025, of a "high probability" of a tsunami in the country as a result of an 8.8 magnitude earthquake off the coast of Russia. Picture: Cristobal Basaure/AFP

Then, on September 18, the second most severe quake of the year hit.

It was in the same place. This time it was 7.8. Damage and injury were, again, minimal.

But it was a much different story for 2025’s third most significant seismic shock.

Some 5500 people were killed on March 28 when a 7.7 rupture occurred 10km below the Sagaing region of Myanmar.

Above magnitude six, it’s considered a threat to structures and lives. Over seven, it means severe damage across large areas and potentially tsunamis.

Metal informational sign indicating a safe area to assemble after an earthquake before the tsunami hits.

Numerous videos uploaded to X, purportedly taken at Chatuchak in Bangkok, show a building under construction collapsing as tradesmen run for cover after a powerful earthquake rocked Myanmar and Thailand. Picture: X

Anything eight and over is a “Big One”. It can destroy cities and alter landscapes.

At nine, it becomes a megathrust. Its radius of total destruction can extend 100s of kilometres.

At the time of writing, 2025 had recorded one quake greater than magnitude eight and 14 between seven and 7.9.

The last time the world experienced one of these was in 2011, with the 9.1 Tōhoku earthquake and tsunami in Japan. It killed some 20,000 people. And the Fukushima nuclear reactor disaster was just one example of the massive damage it did to infrastructure.

The Fukushima Dai-ichi Nuclear Power plant after a massive earthquake and subsequent tsunami on March 14, 2011. Picture: DigitalGlobe via Getty Images via Getty Images

Japan Self-Defense Forces' members in protective gear prepare to transfer workers suffered "beta ray burns" Thursday during their operation at the Fukushima Dai-ichi nuclear plant, at a hospital in Fukushima in 2011. Picture: AP/Yomiuri Shimbun, Takuya Yoshino

Seven years earlier, in 2004, a 9.3 unleashed a tsunami on Indonesia’s Sumatra, killing 228,000.

Is another on the cards?

Governments, researchers and populations living on and around the Ring of Fire fear a “Big One” is on its way.

This combination photo shows an aerial view of Rahmatullah mosque in Lhoknga, Aceh province on January 14, 2005 amid destruction after the December 26, 2004 tsunami (top) and the same mosque on November 27, 2024. Picture: Chaideer Mahyuddin and Jo Saget/AFP

California drifting

You’ve heard of the San Andreas Fault. But what about the Cascadia Subduction Zone (CSZ)?

It’s a Ring of Fire rift that runs from Canada’s Vancouver Island down to Northern California.

It’s a nasty one.

This clash of tectonic plates last let loose as a magnitude nine megaquake 325 years ago. Native American accounts describe an event that hurled trees and people to the ground and shattered the land. The furious tsunami that followed wiped out settlements across Washington state and British Columbia.

Japanese accounts from 1700 label a mysterious wave that flooded its east coast a day later dubbed the “Orphan Tsunami”. Where did it come from? They hadn’t felt any earthquake and was Washington as badly shaken as the legends say?

Now, scientists have found concerning clues in the seabed off California’s Cape Mendocino.

That’s where the 1000km-long Cascadia Subduction Zone ends.

And the 1200km-long San Andreas Fault begins.

View of houses along the coastline at Mendocino, California.

The orange line represents the San Andreas Fault (SAF) section that ruptured in the Great San Francisco Earthquake of 1906. Picture: US Department of the Interior, US Geological Survey

Researchers have long thought the mechanics of both faults were very different. That they were not linked. That what happened on one didn’t affect the other.

That turned out to be wrong.

Core samples reveal that Cascadia magnitude nine megathrusts have triggered a San Andreas response within hours or days at least three times in the past 3000 years.

One of these fits the 1700 Cascadia quake. The other two were 1200 years ago and 1500 years ago.

Another seven big quakes “triggered” the San Andreas within a decade.

The study, published in the research journal Geosphere, has disaster response experts reeling.

The idea of a “double tap” synchronised event striking the entire US Pacific coast is not something they want to think about but now they must.

“It’s kind of hard to exaggerate what a M9 earthquake would be like in the Pacific Northwest,” Oregon State University paleoseismologist Chris Goldfinger warned. “And so the possibility that a San Andreas earthquake would follow, it’s movie territory.”

A protester in protective mask holds a placard during an anti nuclear rally in Tokyo, Sunday, March 27, 2011. Picture: AP Photo/Itsuo Inouye

Alert and alarmed

In July, Japan’s Akusekijima islands were hit by 60 quakes in one day alone. Five tremors were of magnitude five or greater (noticeable shaking and minor damage).

Some 1700 tremors would follow within a month.

Such earthquake swarms are not new. But experts said this one was stronger and longer than anything previously experienced in the area.

Japan experiences about 18 per cent of the world’s earthquakes of magnitude six or over every year.

That’s because the islands have been formed by the confluence of four major ‘Rim of Fire” tectonic plates.

In March, its extensive team of earthquake specialists updated the nation’s threat assessment.

They’re worried by the Nankai Trough.

This 900km fault line sits off the south coast of Japan’s Home Islands between Tokyo in the north and Kyushu in the south and it unleashes a magnitude eight or nine quake every century or so.

It released a magnitude 8.6 slip in 1707 and this triggered Mount Fuji’s last major eruption.

Now, seismologists are 80 per cent certain a magnitude nine megathrust could happen here again within the next 30 years.

Mt Fuji in autumn view from lake Kawaguchiko. Picture: iStock

They warn such a quake could kill 298,000, destroy some 2.4 million buildings and cost $US13 trillion ($A19.6 trillion).

Most of this will result from tsunami waves and the worst-case scenario predicts a 34m high surge inundating Kuroshio town in Kochi Prefecture.

This has prompted Tokyo’s Central Disaster Management Council to issue new building and earthquake protection requirements. It wants stronger and taller sea walls and hundreds of tsunami-proof escape towers built as refuges in high-risk communities.

Japan has felt the wrath of “Big Ones” before.

In 2022, coastal zone residents were given only eight to 30 minutes’ warning. The 40m-tall tsunami waves triggered by the Tōhoku 9.1 megathrust were moving at up to 700km/h.

Fears of an imminent “Big One” caused Japanese Prime Minister Kishida Fumio to cancel an overseas trip in August. The Japan Meteorological Agency (JMA) had just issued an unprecedented “megaquake” advisory.

The warning was the first under a new alert system created after the 2011 disaster and it was triggered by fears that a 7.1 quake in the Nankai Trough was just the start of something bigger.

A rescue worker searches for victims of Mount Merapi eruption at a village hit by pyroclastic flows in Kaliadem, Yogyakarta, Indonesia on October. 27, 2010. A volcanic eruption and a tsunami killed scores of people. Picture: AP Photo/Slamet Riyadi)

Deep understanding

Areas once considered immune to earthquakes are reporting unexpected shocks.

Their ancient fault lines were supposed to have healed. The tectonic forces that created them moved on millions of years ago.

But then came humans.

“Faults can be found almost everywhere,” said seismologist Dr Ylona van Dinther. “Faults in the shallow subsurface are usually stable, so we do not expect shock movements to occur along them,”

Open-cut and deep-shaft mines. Oil wells. Fracking (injecting water into the ground to break up rock and release oil and gas). New research published in the science journal Nature reveals these are causing long-dormant faults to stir in their sleep.

As earthquakes aren’t expected in these areas, building codes are relaxed.

Then, because the pressure release is at relatively shallow depths (a few kilometres), it takes nowhere near as much force as expected to generate damaging ground movements.

But Dr Dinther said these human-induced quakes don’t appear to trigger further seismic activity. Instead, each release of energy lowers the risk of another.

That’s not the case in seismically active zones, however.

This combination photo shows motorists passing debris resulting from the December 26, 2004 tsunami left in Meulaboh town in Aceh province on January 9, 2005 (top) and the same street on November 17, 2024. On December 26, 2004, a magnitude 9.1 earthquake struck the coast of Sumatra in Indonesia. Picture: Philippe Desmazes and Chaideer Mahyuddin/AFP

So European scientists are poking the subterranean bear.

The Fault Activation and Earthquake Rupture (FEAR) project is pumping water into fissures deep beneath the Swiss Alps.

The idea is to trigger earthquakes of up to magnitude one (only detectible by sensors) – just to see what happens.

The water lubricates the faults. The lowered friction induces a seismic rupture.

But every aspect of what happens between injection and release is being carefully examined and the researchers hope this will give them new clues on how to predict natural rifts and understand how they can trigger cascades.

The resolution of seismic research is now far greater than ever before and that’s enabling algorithms to simulate and dissect what’s going on below.

Once, only a handful of seismic sensors would be close enough to offer insight into any given quake. Now accelerometers in personal mobile phones and self-monitoring optical fibre networks can offer hundreds of unique data points.

“Essentially, machine learning can trawl through the data to identify small earthquakes that people don’t have the ability or time to flag,” a US-based earth science organisation reported.

“Large earthquakes may happen along a particular fault once every century or more – far too long a time period for scientists to observe in order to understand the rupture process. Tiny quakes behave much the same as big ones, but they happen much more frequently. So studying the pattern of tiny quakes in the newly expanded earthquake catalogues could help scientists better understand what gets everything going.”