Earthquake activity has returned to the Pacific Ring of Fire, and now a new study has backed up fears that a huge tremor is on the way.
Over the past few weeks, quakes have hit near Japan, Guam and Taiwan around the planet's so-called 'Ring of Fire' - a horseshoe-shaped geological disaster zone.
New research in California says aftershocks can occur on the margins of the area in which the quake took place following a cluster of tremors.
There may also be the possibility of a 'big one' in the immediate area, according to the researchers.
The study, published in in the journal Science Advances, involved an analysis of 101 major earthquakes around the Pacific Ring of Fire between 1990 and 2016.
It showed that most of the aftershock activity occurred on the margins of the areas where the faults slipped during the main earthquakes.
Most earthquakes occur when tectonic plates meet and slide against each other, and quakes occur when the strength of that movement is greater than the strength of the rocks, causing a failure at what is known as the fault line: a line on a rock surface or the ground.
This energy is released as shock waves that lead to an earthquake.
Yes, the area that slipped a lot is unlikely to slip again, as the residual stress on the fault has been lowered to well below the failure level, but the surrounding areas have been pushed toward failure in many cases, giving rise to aftershocks and the possibility of an adjacent large rupture sooner rather than later.'
Dr Lay told the MailOnline that 'it is possible (has been observed) that dynamic stresses from large earthquake can trigger relatively widespread earthquake activation clustered in time.
'Seismologists look for effects of such long-range earthquake interactions regularly now.
'Taiwan, Guam and Japan are far apart relative to the static stress interactions, but one could examine the seismic shaking from an earlier event in the region of a later event to see if small earthquakes were triggered as the seismic waves went by which could have led to a cascade of failures culminating in a larger event.
- A powerful magnitude-7.2 earthquake shook south and central Mexico Friday, causing people to flee buildings and office towers in the country's capital
- In Mexico City, tall buildings swayed for more than a minute as seismic alarms sounded
- Tremors were felt as far away as Guatemala to the south
- At least two people died when a helicopter carrying Mexico's interior minister and the governor of Oaxaca crashed while trying to land
- They had been touring the damage from the earthquake - the senior officials survived
- Mexican President Enrique Peña Nieto tweeted that 'protocols have been activated'
A prolonged 7.2 magnitude quake that rocked Mexico on Friday left nearly a million homes and businesses without power in the capital and south but the only reported deaths came when a military helicopter crashed after surveying the aftermath.
At least 50 homes suffered damage in the southern state of Oaxaca, which, along with Mexico City, is still reeling from earthquakes that caused widespread damage in September.
The epicenter was about 90 miles (145 km) from Pacific coast surfer resort Puerto Escondido in the southern state of Oaxaca and had a depth of 15.3 miles (24.6 km), according to the U.S. Geological Survey.
In Mexico City, tall buildings swayed for more than a minute as seismic alarms sounded throughout the city amid Chinese New Year celebrations, and tremors were felt as far away as Guatemala to the south.
At least two people died when a helicopter carrying Mexico's interior minister and the governor of Oaxaca crashed while trying to land after a tour of damage from the earthquake, officials said. The senior officials survived.
The powerful, sustained shaking on Friday gave way to 225 aftershocks, the national seismology service said, and caused widespread panic.
In Mexico City, the seismic alarm sounded 72 seconds before tremors were felt, Mayor Miguel Angel Mancera said, giving residents time to flee to the streets.
The Oaxacan town of Jamiltepec appeared to sustain the heaviest impact in the southern region, with 50 homes damaged along with a church and government building, the state's civil protection agency said.
Patients were evacuated from a hospital there and from another in the nearby town of Putla Villa de Guerrero. On a local highway, a fire ignited when two high-tension electric cables struck each other.
In the town of Pinotepa Nacional close to the quake's epicenter, a photo obtained from Oaxaca's civil protection agency showed a single-story building where a portion of the brick facade had crumbled into the street. A hospital was also damaged, and a collapsed structure blocked a major highway.
About 100,000 people in Oaxaca had lost power, the state's governor said.
Tremors were felt as far away as Guatemala to the south.
Images in the media appeared to show bricks and rubble fallen from buildings, and products tumbling off shelves in a supermarket.
In Mexico City, tall buildings swayed for more than a minute as seismic alarms sounded, with older structures in the chic Condesa neighborhood knocking into each other, and some cracks appearing in plaster and paintwork.
The Popocatepetl volcano south of the capital sent a kilometer-high column of ash into the sky, said Mexico's disaster prevention agency.
- 14 earthquakes in the past 24 hours
- 18 earthquakes in the past 7 days
- 37 earthquakes in the past 30 days
- 381 earthquakes in the past 365 days
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