A series of & # 39; wobbles & # 39; comes before giant earthquakes, a new study has discovered, and it can help scientists predict when future disasters will happen.
Scientists from Ohio State University found that months for Japan's strongest ocean in 2011, land masses in the country caused a huge & # 39; wobble & # 39; undergo.
The 2011 earthquake released a tsunami that killed thousands of people and scientists say the wobble it took months before.
The team behind the latest discovery hopes future wobble seismologists can warn of upcoming disasters and give countries time to prepare, but would all & # 39; at risk countries & # 39; required to install a large and robust sensor network.
Although the small shifts & # 39; imperceptible & # 39; were, they were & # 39; obvious & # 39; in data measured by more than 1,000 GPS stations around the country, scientists say.
Scientists from Ohio State University found that months before Japan's strongest peak in 2011, land masses in the country were enormous. wobble & # 39; submerged
The study, published in the journal Nature, looked at the data surrounding the Tohoku-oki earthquake of March 9 that killed 15,500 people.
An early shift in land swept the land mass of the land from east to west, and back, in a & # 39; wobble & # 39; lasting months, the Ohio team found.
Study co-author Professor Michael Bevis said that what they found in Japan was a huge but very slow wobble – something that has never been seen before.
& # 39; But are all the giant earthquakes preceded by wobblers of this kind? We don't know, because & # 39; we don't have enough data, & # 39; said Ohio State investigators.
& # 39; This is one more thing to note when assessing seismic risk in subduction zones such as those in Japan, Sumatra, the Andes, and Alaska. & # 39;
The new study found that Japan's land masses shifted several times the equivalent of just a fraction of an inch per month over a period of five to seven months before the 2011 earthquake.
Scientists from Germany, Chile and the United States analyzed this data and saw a reverse shift in the country.
They found that it was reversed by a fraction of an inch to the east, then to the west, then back to the east.
Those moves were & # 39; significant & # 39; different from the constant and cyclical shifts that are the land masses & # 39; make the earth continuous, the team explained.
& # 39; The world is made up of plates that always move in one way or another. Movement is not uncommon. It's this style of movement that's not unusual, "Bevis said.
The Earth Sciences expert said the wobble could indicate that in the & # 39; months before the earthquake, the plate beneath the Philippine Sea began with a & # 39; slow slip event & # 39 ;.
The catalyst for the shake, Bevis explained, was a relatively soft and & # 39; silent & # 39; suppression of two adjacent oceanic plates below Japan.
This silent shift eventually triggered a massive land to the west and down that swept the Pacific plate and plate beneath Japan, generating powerful seismic waves that shook the entire country.
The study, published in the journal Nature, looked at the data surrounding the Tohoku-oki earthquake of March 9 that killed 15,500 people
Japan was devastated by the natural disaster that permanently shifted large parts of Honshu, the main island of the country, several meters to the east.
It launched tsunami waves over 130ft high, destroying the homes of 450,000 people and sending several nuclear reactors at the Fukushima Daiichi nuclear power plant into meltdown.
A stiff stream of toxic, radioactive materials injected the atmosphere, forcing thousands in the neighborhood to flee from their homes.
Researchers are trying to determine the scope of the & # 39; s next major earthquakes and to predict where and when they & # 39; m likely to occur.
But the & # 39; when & # 39; is much harder than the & # 39; where & # 39 ;, according to the Ohio team.
Unfortunately, the benefits of this study are not widespread, as not all countries are equipped with Japanese GPS technology.
Japan was devastated by the natural disaster that permanently displaced large parts of Honshu, the main island of the country, several meters to the east
Study lead author Dr Jonathan Bedford, a researcher at the GFZ German Geosciences Research Center, said it was not possible to apply the findings to other vulnerable subduction zones.
Many countries in zones vulnerable to earthquakes are missing the technology available in Japan, which is & # 39; one of & # 39; s largest GPS monitoring systems in & # 39; has a world.
That progressive system provided ample data, enabling the research team to identify landmass swings that didn't happen many months before the earthquake.
Other countries, including Chile and Indonesia, which were hit by devastating earthquakes and tsunamis in 2010 and 2004, respectively, had much less extensive systems at the time of those disasters.
The researchers analyzed similar data from Chile's 2010 earthquake, and found evidence of a similar wobble.
Dr Bedford said the data & # 39; were just good enough to record the signal. & # 39;
He added: & # 39; We really need to monitor all major subduction zones with high density GPS networks as soon as possible. & # 39;
The research was published in the journal Nature.
The Earth moves under our feet: Tectonic plates move through the mantle and produce earthquakes as they scrape against each other
Tectonic plates are composed of & # 39; Earth's crust and the upper part of & # 39; a cloak.
Below is the asthenosphere: the warm, viscous conveyor belt of rock on which tectonic plates ride.
The Earth has fifteen tectonic plates (pictured) that together form the landscape that we see around us today
Earthquakes typically occur at the boundaries of tectonic plates, where one plate dips below the other, protrudes the other, as the flat edges scrape next to each other.
Earthquakes rarely occur in the middle of plates, but they can happen when old faults re-activate as shrinkage far below the surface.
These areas are relatively weak compared to the surrounding plate, and can easily slip and cause an earthquake.
. (tagsToTranslate) dailymail (t) sciencetech (t) Japan