Quake odds fall in Cantabrians' favour
Many Cantabrians are hoping 2013 will be a quiet year seismically and their hopes will be bolstered by the most recent probabilities from GNS Science.
The probability of a significant quake somewhere in the central Canterbury earthquake zone is continuing to drop.
Since the start of this year, there has been a slow but steady decline in the probabilities for the lower magnitude aftershocks of about 1 per cent per month.
The most recent aftershock probabilities from GNS Science released yesterday show the probability of a magnitude 5.0 to 5.4 shake in the next 12 months is 67 per cent, compared to 69 per cent in October and 82 per cent in January.
Over the same period there is a 28 per cent probability of a magnitude 5.5 to 5.9 aftershock in the next year, down from 29 per cent in October and 39 per cent in January. There is now only a 9 per cent probability of a magnitude 6.0 to 6.4 aftershock in the next year, down from 13 per cent in January, and a 2 per cent probability of a magnitude 6.5 to 6.9 aftershock, down from 4 per cent in January.
There was a 1 per cent probability of a magnitude 7.0 or higher. This remained unchanged from November.
The calculations are for the entire aftershock zone, which stretches from the Canterbury foothills in the west to Pegasus Bay in the east, and from Rangiora to Tai Tapu in the south.