Hidden aftershocks of the 2011 Mw 9.0 Tohoku, Japan earthquake imaged with the backprojection method
Article first published online: 29 OCT 2013
©2013. American Geophysical Union. All Rights Reserved.
Journal of Geophysical Research: Solid Earth
Volume 118, Issue 10, pages 5564–5576, October 2013
How to Cite
2013), Hidden aftershocks of the 2011 Mw 9.0 Tohoku, Japan earthquake imaged with the backprojection method, J. Geophys. Res. Solid Earth, 118, 5564–5576, doi:10.1002/2013JB010158., and (
- Issue published online: 18 NOV 2013
- Article first published online: 29 OCT 2013
- Accepted manuscript online: 10 OCT 2013 04:59PM EST
- Manuscript Accepted: 2 OCT 2013
- Manuscript Revised: 30 AUG 2013
- Manuscript Received: 25 FEB 2013
- hidden aftershocks;
- 2011 Tohoku Earthquake
 The first 25 h of the aftershock sequence following the 11 March 2011 Mw 9.0 Tohoku, Japan earthquake is investigated using a backprojection method. In total, 600 aftershocks are imaged during this time period. These aftershocks are distributed over a 500 by 300 km area and include many events in the outer rise. The backprojection events are compared with the Japan Meteorological Agency (JMA) catalogue, which is composed of earthquakes recorded by local seismic networks in Japan. Surprisingly, half of the backprojection events are not found in the JMA catalogue. These events cluster near the Japan Trench and in the outer rise and fill in gaps in the spatial distribution of the early aftershock sequence where large main shock slip is thought to have occurred. These results show that the JMA magnitude of completeness is very high near the trench following the 2011 Tohoku main shock, and earthquakes as large as magnitude 6.8 went undetected by local seismic networks.