Glacial earthquakes

Publication Type  Journal Article
Year of Publication  2003
Authors  Ekstrom, G.; Nettles, M.; Abers, G. A.
Journal Title  Science
Volume  302
Issue  5645
Pages  622-624
Journal Date  Oct 24
ISBN Number  0036-8075
Accession Number  ISI:000186119900052
Key Words  subduction zone; waves; slow; mechanism; alaska; event; fault; flow
Abstract  

We have detected dozens of previously unknown, moderate earthquakes beneath large glaciers. The seismic radiation from these earthquakes is depleted at high frequencies, explaining their nondetection by traditional methods. Inverse modeling of the long-period seismic waveforms from the best-recorded earthquake, in southern Alaska, shows that the seismic source is well represented by stick-slip, downhill sliding of a glacial ice mass. The duration of sliding in the Alaska earthquake is 30 to 60 seconds, about 15 to 30 times longer than for a regular tectonic earthquake of similar magnitude.

Notes  

735MVTimes Cited:27Cited References Count:24

URL  <Go to ISI>://000186119900052
DOI  DOI 10.1126/science.1088057