On Monday, a 5.2 magnitude earthquake shook San Diego. The epicenter was located about 2 miles south of Julian.It didn't cause major damage and no injuries were reported.But, it was the biggest earthquake in our region since the 2010 earthquake near Guadalupe Victoria, which was a 7.2 magnitude earthquake.On Midday Edition, we make sense of the earthquake with a seismologist. Plus, we hear some practical tips on how to prepare for the next quake, whether or not it's "The Big One."Guests:Alice Gabriel, seismologist and associate professor at UCSD's Scripps Institution of OceanographyJacob Margolis, science reporter for LAist and host of "The Big One: Your Survival Guide"