Reveal earthquake 'hot spots' in the world

A new study finds that the most powerful earthquakes that hit Earth, such as the 9-magnitude strong earthquake, shook Japan last year, often appearing in certain 'hot spots'. Our planetary crust.

According to the article just published in Solid Earth, about 87% of the 15 largest earthquakes of the past century have occurred in intersections between certain areas on stretching ocean plates (named collectively are faulty areas on the sea) and submerged areas, where a plate of tectonics slides beneath another area.

To get this result, scientists used a method of data collection to find out the relationship between the places where earthquakes occurred over the past 100 years, the intensity and geological origin. of those earthquakes.

The glowing spots on the simulated map
Earthquakes occurred during the last 100 years.

At the bottom of the ocean there are many underwater ridges that run horizontally, such as the mid-Atlantic mountains stretching north - south between the US and Africa. These ridges divide the two tectonic plates that move apart when lava erupts, solidifies and creates new rocks. The mountain range between the ocean moves back and forth, creating the zigzag shaped lines. Fault areas are scars left behind by this process.

Fault areas are typically characterized by large underwater ridges with intertwined valleys between them. Millions of years after forming in the ocean, these ridges gradually progress to a submerged area, usually on the other side of the ocean.

The researchers hypothesize that these underwater mountains are "torn apart" as they enter the submerged zone, causing great pressure to accumulate over hundreds or thousands of years before finally releasing and creating. Great earthquakes.

These areas are prone to earthquake 'super cycles' , where intense seismic episodes occur after a few hundred or several thousand years, Dietmar Müller - a research author from the University of Sydney - emphasized. .

Many of these areas may not have been evaluated as being particularly at risk, because the seismic hazard warning maps are often made primarily based on the Data collected after 1900. For example, the terrifying Tohoku earthquake that attacked Japan in 2011 was not anticipated by high-risk maps.