This blog provides commentary on interesting geological events occurring around the world in the context of my own work. This work is, broadly, geological fluid dynamics. The events that I highlight here are those that resonate with my professional life and ideas, and my goal is to interpret them in the context of ideas I've developed in my research. The blog does not represent any particular research agenda. It is written on a personal basis and does not seek to represent the University of Illinois, where I am a professor of geology and physics. Enjoy Geology in Motion! I would be glad to be alerted to geologic events of interest to post here! I hope that this blog can provide current event materials that will make geology come alive.

Banner image is by Ludie Cochrane..

Susan Kieffer can be contacted at s1kieffer at gmail.com

Tuesday, February 22, 2011

Major earthquake causes extensive damage in Christchurch, New Zealand

Map of felt effects of the Christchurch earthquake
from Geonet
Update at 11:00 a.m. on 2/23/11:  Dave Petley's landslide blog here has an excellent summary of reasons that this quake was so devastating compared to the higher-magnitude September event.

Mid-day, Tuesday, a major earthquake struck 10 km south-east of Christchurch, New Zealand.  The focal depth was shallow, only 5 km.  The USGS called it a magnitude 5.5; the press and Geonet are saying that it is a 6.3.  65 people have been reported killed at this time, the toll is likely to go higher, and damage is extensive. There has been at least one strong aftershock.

The graph is a preliminary summary  of damage, keyed to the Modified Mercalli intensity scale.  MM8 (dark orange) is heavily damaged, light orange is damaging, yellow is slightly damaging, and green is strong. The red square marks the epicenter.  Click on the Geonet link in the caption to get an updated version of this map.

In an earlier post, I discussed the damage caused by the September 3, 2010, M7.1 earthquake, also near Christchurch. A lot of the damage then was caused by liquefaction, and that is likely to be a problem this time as well.  Many buildings had been damaged by the earlier earthquake, repairs had not been completed, and so they were vulnerable to the intense shaking that occurred.

There is more information on Dave Petley's Landslide Blog, and a good discussion of the geologic setting on Chris Rowan's Highly Allocthonous blog. Information, including some videos, is starting to come in to CNN.COM.  This one shows a bit of footage taken during the earthquake at the very beginning of the video.

Our thoughts and sympathies go out to our Kiwi friends.


1 comment:

Muhammad Abu Bakar said...

A moderate earthquake was felt in Khyber Pakhtunkhwa, Northern Areas, FATA and Punjab.
for more details visit