On February 22, 2011, at 12:51pm (NZST), a 6.3 magnitude quake hit. The epicentre was only 10 km (6 miles) from the centre of Christchurch and at a depth of 5 km (3.1 miles). The residents of Christchurch had been living with aftershocks from a 7.1 quake that occurred 6 months prior. While the quake was not as strong as the September quake, the surface effect forces were far greater. The simultaneous vertical and horizontal ground movement was near impossible for buildings to survive. An already quake-crippled city was decimated.