earthquakes might set off incredibly slow earthquakes thousands of
miles away, new research suggests.
findings, detailed online Sept. 11 in the Journal of Geophysical
Research-Solid Earth, shed light on how earthquake zones might
communicate with each other over large distances, scientists added.
cluster of devastating earthquakes that rocked the globe during the
past decade from Japan to Sumatra to Haiti is one reason why
scientists are investigating whether temblors in different parts of
the world are linked to one another. Although research to date
suggests that major quakes aren't likely to trigger other massive
quakes around the globe, they can set off tremors worldwide.
researchers find that large quakes might also trigger mysterious slow
earthquakes thousands of miles away. One kind of slow earthquake
known as a slow-slip event can last for weeks, shifting the Earth as
much as an ordinary earthquake of magnitude of 7 would in mere
investigators focused on the magnitude 8.8 Maule earthquake that
struck Chile in 2010. They found it generated surface waves that,
within hours, set off tremors in the Guerrero region of southwestern
Mexico 4,140 miles (6,660 kilometers) away. Data from GPS stations
also revealed the earth there began moving southward at the same time
tremors there began.
tremors and movements of the GPS stations lasted for about six months
after the 2010 Chile quake.
an observation may indicate that the Maule earthquake triggered a
slow-slip event in Guerrero," said researcher Dimitri Zigone, a
seismologist at the University of Southern California in Los Angeles.
Guerrero lies a subduction zone, where a tectonic plate under the
Pacific Ocean is diving under the continental North American plate.
The seismic energy from Chile apparently increased the stress in the
segment of the subduction zone near Guerrero, which may explain the
resulting slow-slip event.
fact large quakes can have effects so far away could be important
because it may change the recurrence time between earthquakes in a
specific location," Zigone told OurAmazingPlanet. "Usually
we assume that the seismic cycle — the recurrence between
earthquakes — is regional, on a single fault system or at a plate
boundary, for example. If these large-scale interactions exist, it
may indicate that even at large distances, a mega-earthquake can
modify the conditions in another region."