An earthquake with magnitude of 6.9 struck near Ozernovsky village in the southern part of Russia’s Kamchatka peninsula early on Friday. Its effect was felt in the city of Hakodate in Japan, according to The Japan Times, leading the country’s meteorological agency to issue an early warning that erroneously mentioned the magnitude of 9.9. That warning was withdrawn minutes later, but if it had been true, this would have been the strongest earthquake in the history of mankind, surpassing the 1960 quake that struck Chile.
According to US Geological Survey, some of the most powerful earthquakes measured by instrument include:
Biobio, Chile: Commonly referred to as the Valdivia earthquake, the largest quake ever killed 1,655 people and left two million homeless.
Great Alaska Earthquake, 1964: The magnitude 9.2 quake lasted nearly five minutes and killed 130 people.
Sumatra earthquake, 2004: It triggered a tsunami in the Indian Ocean with a magnitude of 9.1, killing over 2.5 lakh people.
Tohoku quake, 2011: This was also a magnitude 9.1 earthquake and caused the Fukushika nuclear disaster along with triggering a massive tsunami in which over 1,800 people died.
Kamchatka quake, 1952: This was the world’s first recorded 9.0 earthquake that sent a 30-foot tsunami towards Hawaii.
What Would A 9.9 Quake Look Like?
As per US Geological Survey, the magnitude of an earthquake is related to the area of the fault on which it occurs – the larger the fault area, the larger the earthquake.
Though no official data has been released about such a megathrust quake, experts say a 9.9-magnitude tremor would release roughly 32,000 times more energy than today’s 6.9 quake, and significantly more than the 1960 Chile and 2011 Tohoku quakes.
It would also require a massive tectonic fault rupture spanning roughly 3,000 to 5,000 kilometres and the ground would shake for at least five minutes or longer.
There will be total destruction near the epicentre and the seafloor could also see massive displacement. Large sections of continental coastlines could permanently subside or uplift by several meters, changing local geography and submerging tidal lands.
Some experts have claimed that an event of this scale can slightly alter the Earth’s rotation speed (micro-second shifts) and tilt the axis.
According to USGS, the magnitude scale is open-ended, meaning that scientists have not put a limit on how large an earthquake could be, but there is a limit just from the size of the earth. A magnitude 12 earthquake would require a fault larger than the earth itself.
Japan’s Connection To Earthquakes
Japan sits directly on the Pacific Ring of Fire, a 40,000-kilometre horseshoe-shaped zone of high seismic and volcanic activity surrounding the Pacific Ocean. This is why the island nation experiences so many earthquakes.
Further, Japan sits at the meeting point of four major tectonic plates: the Pacific, Philippine Sea, Eurasian, and North American (or Okhotsk) plates that shift continuously.
This constant shifting makes Japan home to over 100 active volcanoes, including Mount Fuji, and causes roughly 1,500 earthquakes every year.
