More than 200 people lost their lives in Mexico City on Tuesday to a magnitude 7.1 earthquake centered in Mexico‘s state of Puebla. It remains to be seen if this seismic activity is related to the magnitude 8.1 quake that struck a nearby region just two weeks prior but most experts agree that a significant aftershock is all but imminent. CBS NEWS science and futurist contributor, Dr. Michio Kaku, spoke to CBSN on how earthquakes work and why this one was so devastating. WATCH NOW!