New Zealand has always been my focus, so here is a preliminary summary in graph format for 2011.
Spent a lot of time working on these, like 365 days
you can see the full size images
here
in about a months time I should be able to draw up the final, revised, updated numbers when Geonet go over the last couple of months. I've already
done the first 3 months of numbers per day and they are double the preliminary count per day, and average out at 78 per day over 90 days I'm not
expecting the energy count to change much, its the biguns that determine the size of the columns on those graphs and its pretty unlikely Geonet missed
any mag 5's.
As you will see its not always the days with a large number of events that have the high energy release,
the largest energy release was on April 18th 6.6Mw SW of L'Esperence Rock south of the Kermadec Islands followed by the Tihoi 6.462 on July 5th on the
edge of Lake Taupo ( volcano) not the Feb 21 Port Hills 6.343 or June 13 Taylors Mistake/Redcliffs 6.411 which had the highest numbers of events
(aftershocks). The first offshore East Cape quake in September 15th was bigger (6.336) than the November 18th one (6.109) and released more energy,
although the November one had multiple aftershocks which brought the numbers count way up for that day (90).
As far as patterns go the only ones I can see are the aftershocks which seem to be pretty standard especially for the shallow Christchurch Mag 6
events, leading up to big events the numbers either fall away prior or steadily build up, so the perception that prior to a big one the numbers drop
away is wrong eg prior to the Feb 22 event the numbers built up steadily from 7 per day to 33 per day over 23 days, whereas prior to the June 13 event
the numbers fell steadily over 5 days from 50 to 22 per day. The July Tihoi had a steady 6 to 13 per day in the 6 days prior.
2011 (59) becomes the 3rd highest year for numbers of quakes above Mag 5 per year after 2009 (74) and 1995 (114) over the last 171 years of records,
and equals 1929 and 1995 with 7 Mag 6's per year.
edit on 1-1-2012 by muzzy because: (no reason given)
Oh yeah, over the holidays I started on that rehash of my Historic NZ Earthquakes 1840-2011, moving it over to Wordpress, you can see the Timeline
graph for Mag 5+ quakes in 2011 and the numbers count for the 171 years comparison count there.
I've thrown in the 2010 "hotspots" maps I did earlier in the year and will do the same for 2011 when I get the time
eqarchives.wordpress.com...
hopefully the icons on the interactive maps load for you, I had trouble with mine a few times, some of them come up as blue google markers as default,
but the details of the quakes are still there if you click on the icon.
edit on 1-1-2012 by muzzy because: (no reason given)
