Ground motion information and field reports have become available from the magnitude 6.3 Mw earthquake that caused extensive damage to Christchurch, New Zealand and the surrounding areas at 12:51pm local time (23:51 UTC) on February 21, 2011.
More information about the earthquake damage (including photos and engineering information) has been posted on the clearinghouse by the New Zealand Society for Earthquake Engineering.
Day 1 Report of Damage from Christchurch Earthquake (pdf file, 4.1 MB) by Kenneth J. Elwood, Associate Professor, Department of Civil Engineering, University of British Columbia. Professor Elwood happened to be in Christchurch during the earthquake for a seminar on seismic assessment of existing buildings, and continues to send observations from the damaged region.
Strong-motion records are available from the Center for Engineering Strong Motion Data.
Comparing the ground motion from the Feb 2011 and the Sept 2010 earthquakes (Version 2) (pdf file, 635 KB) by Dr. Brendon Bradley, Lecturer, Civil and Natural Resources Engineering, University of Canterbury – UPDATED 02/24/2011
Processed ground motion recordings from the M 6.3 earthquake on February 22, 2011 – source: GeoNet, New Zealand’s network of seismographs
Map showing PGA from Recording stations around Christchurch, NZ – source: GeoNet, New Zealand’s network of seismographs