Seismic waves from the 2010 Chile earthquake triggered icequakes - quakes that rupture ice sheets - in Antarctica, reports a study published online this week in Nature Geoscience. Large earthquakes are known to trigger seismic activity in remote parts of the Earth’s crust, but these results indicate that ice sheets are also sensitive to such triggering.
Zhigang Peng and colleagues analysed seismic data from Antarctica recorded during six-hour periods before and after the magnitude 8.8 earthquake in Chile in 2010. The data showed several small icequakes in the hours following the Chilean quake. The authors suggest these were triggered by seismic waves radiating away from the Chilean earthquake’s epicentre and passing through the ice sheet. The results highlight a previously underappreciated interaction between the solid Earth and the frozen liquid portion of its crust, and imply that large, distant earthquakes might affect ice sheet dynamics.