24 earthquakes over M3.0 in a 1.5-hour period. That's pretty significant. I called my mom about 10 minutes after the 7.2 magnitude "big one", it was pretty crazy in San Diego.
I moved from San Diego two years ago, anything over M3.0 is a good-sized quake and will definitely make some big buildings sway.
I am more concerned though about the shack villages in Mexico that will no doubt be demolished, and with so many aftershocks and the risk of larger ones in the days to come, I think it be appropriate for prayers to be sent their way!