The number of large earthquakes in Southern California and Baja California has increased significantly in 2010. There have been 70 quakes greater than 4.0 magnitude since the beginning of the year. There were 30 in 2009 and 29 in 2008. Scientists are so far unable to explain the uptick, but some think it may mean Southern California is entering a more active seismic period.

Read it at The Los Angeles Times