Chile’s earthquake triggered ‘icequakes’ in Antarctica
Published : 2014-08-11 21:07
Updated : 2014-08-11 21:07
PARIS (AFP) ― A monster earthquake that struck Chile in 2010 also unleashed minor “icequakes” in Antarctica nearly 4,700 kilometers to the south, scientists said.
Sensors recorded small tremors in West Antarctica within six hours of the Chilean mega-shock, providing the first evidence that the world’s greatest ice sheet can be affected by distant but powerful quakes, they said.
Twelve out of 42 monitoring stations dotted across the vast region showed “clear evidence” of a spike in high-frequency seismic signals, the team reported in the journal Nature Geoscience.
The signals tallied with signs of ice fractures near the surface, they added.
The Feb. 27, 2010, quake, which occurred just off the coast of Chile’s Maule region, measured 8.8 in magnitude, making it one of the largest ever recorded.
It killed more than 500 people and inflicted an estimated $30 billion in damages.
The main shock from the event triggered micro-quakes as far afield as North America, as the passing shock wave caused shallow faults to slip in tectonically active regions.
Geologists have long wondered how the ice sheets in Greenland and Antarctica ― whose underlying rock is considered seismically peaceful ― would respond to gigantic but distant quakes.
Until a few years ago, there were no means to explore the idea.