Haiti aftershock: Why a 6.1 quake isn't that powerful

A magnitude 6.1 aftershock struck near Port-au-Prince on Wednesday morning. With so many buildings damaged by the major Haiti earthquake last week, there are concerns about danger. But there's a world of difference between today's quake and the 7.0 earthquake that did so much damage last week.

The aftershock that hit Haiti shortly after 6 a.m. on Wednesday frightened Haitians traumatized by last week's much stronger earthquake and raised concerns that it could bring down buildings weakened by the original earthquake and cause more loss of life.