The image above is National Network for the Big 7.1 Earthquake to hit 40km west of Christchurch on September 4th at 4:35am which caused widespread damage right through Canterbury including Christchurch.
The image above is the first two hours of shaking after the September 7.1 earthquake.
The image above is the first day of shaking in Christchurch after the 7.1 on September 4th. Notice however that the image has not got as many wobbles on it. This is because the scale of the graph was increased by a couple of orders of magnitude.
The image above is the national Quake Drum network for the February 22nd 6.3 Earthquake which hit just 10km southwest of the City CBD and caused major terminal damage to the city in which will take many man yeas to fix.
The image above is the First hours of the quake and shows the relative shaking.
This image shows the Shaking for the day of February 22nd for the 6.3 quake. Again the scale of the graph was increased by a couple of orders of magnitude, but here you can just see how much energy is being released in those first few hours. Much more than the one on September 4th.
As a comparison the image above shows the 2009 Samoa earthquake was an 8.1 M submarine earthquake that took place in the Samoan Islands region at 06:48:11 local time on September 29, 2009. The distance between Samoa and Auckland is 2900km so this can give you an appreciation how large that earthquake was and how sensitive the quake drums are.
And as a comparison here is also the quake drum in NZ for today when Japans 8.9 Earthquake hit. Japan is about 9000km away from NZ and every drum in NZ picked up the earthquake which shows the absolutely power of this Earthquake.
JUNE 13th 2011 Christchurch 5 .7 and 6.3 Earthquakes
Above is the national drum network. the first big strike is the 5.7 quake and then the big one after is the 6.3 which was only 80 minutes later!
This image above is the Christchurch quake drum. This shows the first shock the 4.6 inbetween and then then you can see the difference in length of time from the 6.3 in shaking.
The image above is the same as the one but you can see how the sensitiveness of the drum has been adjusted and the activeness of the ground in those 12 hours after the 5.7 earthquake.