Still continues to be some very large aftershocks. USGS have put up some data on it. They are obviously getting lots of queries.
Question: Can we expect many aftershocks to this earthquake?
Answer: There have been numerous aftershocks detected following the recent magnitude 9 megathrust earthquake. The U.S. Geological Survey National Earthquake Information Center (USGS/NEIC) continues to record many newly occurred aftershocks. As of 1:00PM, MST, December 29, sixty-eight aftershocks have been cataloged. The largest occurred about three hours after the main shock and is now assigned a magnitude of 7.1. Thirteen of the aftershocks thus far cataloged have magnitudes of 6.0 or larger. There have been no reports of tsunamis being generated from the aftershocks. We know from past experience that the number of aftershocks will decrease with time. However, the number of aftershocks can be quite variable. There might be short episodes of higher activity as well as lulls in activity, but the overall trend will be for fewer aftershocks as time goes by. Seismologists are not able to predict the timing and sizes of individual aftershocks.
The number of cataloged aftershocks will be constantly changing, as new aftershocks occur and as USGS/NEIC analysts newly locate aftershocks from the first few days after the earthquake. Magnitudes assigned to individual aftershocks may change somewhat as new data come in. An up-to-date catalog of analyst-processed USGS/NEIC epicenters and magnitudes is at