when did the christchurch quake happened?
2011 Christchurch earthquake
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 The earthquake produced severe shaking that registered VIII on the Mercalli scale in and around the city of Christchurch , destroying some buildings and causing additional damage to many structures affected by previous earthquakes . The damaged tower of the historic Lyttelton Timeball Station collapsed before dismantling work could be completed . The earthquake downed phone lines and triggered widespread outages , which left around 54 @,@ 000 households without power . Rebuilding costs in Christchurch increased by NZ $ 6 billion ( US $ 4 @.@ 8 billion ) owing to the additional damage from the quake . Forty @-@ six people suffered injuries , and one elderly man died after being knocked unconscious . 

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 Despite the appeal , thousands of onlookers filled the street on Sunday morning of 5 August . Punctually at 8 am , a series of short explosions were heard , followed by another series a couple of seconds later . The building collapsed towards the north as planned , and the implosion manager from Controlled Demolition , Inc. was quoted as saying that " it went a bit further than I had hoped so I am lucky " . The explosions were heard around Christchurch . 

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 Seismologists reported that the earthquakes were part of a prolonged aftershock sequence associated with the major magnitude 7 @.@ 1 earthquake of September 2010 , which includes the February 2011 event . They were succeeded by multiple lighter aftershocks ; the strongest , a moderate magnitude 5 @.@ 1 MLstruck a minute after the event. another tremor 5 @.@ 0 ML struck the region two days later . Despite significant energy release , the earthquakes were believed to have increased the risk of an additional aftershock of similar magnitude ; calculations from GNS Science indicated a 23 percent probability of a magnitude 6 @.@ 0 – 6 @.@ 9 ML earthquake occurring in the Canterbury aftershock zone within the 12 months following the event . Weeks later , a magnitude 5 @.@ 4 ML tremor jolted Christchurch overnight on 22 June , causing additional damage and prompting evacuations . 

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 The June 2011 Christchurch earthquake was a shallow magnitude 6 @.@ 3 ML earthquake that occurred on 13 June 2011 at 14 : 20 NZST ( 02 : 20 UTC ) . It was centred at a depth of 6 km ( 3 @.@ 8 mi ) , about 10 km ( 6 mi ) from Christchurch , which had previously been devastated by another magnitude 6 @.@ 3 ML earthquake in February 2011 . The June quake was preceded by a magnitude 5 @.@ 9 ML tremor that struck the region at a slightly deeper 8 @.@ 9 km ( 5 @.@ 5 mi ) . The United States Geological Survey reported a magnitude of 6 @.@ 0 Mw at a depth of about 9 km ( 5 @.@ 6 mi ) . 

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 Mount Tarawera in New Zealand erupted along a rift zone in 1886 , killing 150 people . 
