Christchurch Shakes Again and Again
Since September 4 2010
seismic activity in the Christchurch region, New Zealand
has remained well beyond background levels.
latest entries precede original post
2018
January
The earthquake spread in January 2018 includes recent reactivations in the Christchurch region -as well as in the larger subduction zone down the eastern diagonal flank of both islands - following the energy shift provided by the Jan 2 perigee closest orbiting moon for the year.
January 2018 is a watch and see period due not only to the perigee moon but the energised mid January New Moon [17th] and the following first eclipses of 2018 [Feb 1 and Feb 16 in NZ which all sustain themes set in place from 2017 year's end Dec 31/Jan1 2018 which indicate higher than usual risk of structural collapse -as indicated in this post for the January forecast
Counting back from Jan 20 there have been at least 8 quakes over M3 [and considerably more M2+] in the larger Canterbury region
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| Geonet data - highlighting added |
2017
October
Since November 2016 with the M7.8 Kaikoura quake, attention shifts to the larger region involved in the subduction of the Pacific plate under the Australian plate, placing the eastern flank of the North Island down to Cook Strait as the anticipated next high risk zone
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| GNS SCIENCE |
September
A M7.1 quake in Mexico has occurred with strong energetic similarities to the February 22 2011 quake
This very similar energy to Feb 2011 has found expression on another continent.
2016
February 29 severe shaking from a M4.3, 5kms deep centrally located near Cashmere has further revisited the horrors of 5 years ago, though no initial reports of damage or injury.
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| Quakemap energy chart showing a significant late Feb spike |
Feb 14 M5.7 offshore from New Brighton reignites a higher level of seismic unrest.
The likelihood of a M5.0-5.9 quake was 49%, before today's quake - and 5.7 % for a M 6.0-6.9 quake.
There was less than a 1% likelihood of an earthquake larger than magnitude 7 according to Geonet
The last 100 quakes in the moderate to severe range -via Geonet extensively populate the plate boundary through the main islands of New Zealand
This data includes recent other large events: a Jan 28 2016 M4.1 south of Christchurch and a M5.7 at St Arnaud, south of Nelson on Feb 9 2016
April 2015
Two M3.8 quakes within the period April 5-7
The first in the hills above Lyttelton, the second above Governor's Bay
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| April 7 |
data & graphics from Christchurch Quake Map
2014No significant quake resurgence in 2014 but from mid December, some enhanced [though not significantly damaging] seismicity up to M4.5
April 13
Enhanced global seismicity is noted in the building phase of the full moon lunar eclipse [exact on Tues 15th -and with extra complexities -Read 2014 extreme events forecast ]
Christchurch experienced a M4.2 -5kms deep at 8.36am near the Port Hills
March 20 saw a M4.04 west in the Greendale fault zone.
M4.74 is presently the pass mark to get into the top 100 for the region
April so far continues the pattern of intermittent events M4+ in a more active recent period but the month has further intense potentials.
This day also saw a major quake in the Solomons Region M7.6 and Christchurch does seem to have echo events when other distant big events occur.
The first quarter of 2014 has passed with no major destructive events though events over M4 remain very intermittent.
This graphic from Quakelive shows the pattern of declining intensity.
December 2013
A pattern of very minimal activity interspersed with random higher events is continuing
A flurry occurred across the region on Dec 19 in the period 12.44am-1.15 am to a maximum of M3.9 - though this was a seafloor event off Parklands & not newsworthy it seems.
November 2013
A pattern of very minimal activity interspersed with random higher events is continuing
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| November 18 M4.6 |
report
October has ended with a bang after an unusual lull period lasting some 20 days
M4.2 at the eastern end zone of the Greendale Fault at 4.21 am followed by a nearby M3.3
Then at 9.45 am a M3.8 50kms n/e of Mt Cook - in range of the Alpine Fault
This activity comes in the wake of extensive high activity on the sun during October particularly in the last week - multiple M and X level flares - high level magnetic discharges which have been shown to precede noticeable seismic responses on earth.
October has begun the first week with more intense seismicity in Canterbury e.g. Oct 1st M4.6 seafloor off New Brighton, and 2 shallow events at M3.3 on subsequent days one east one west.
Generally there have been lower magnitude sporadic events in recent months with the odd one over M4
Also read October 2013 astro-analysis for relevant background material to this larger than usual lately event
August 25 2013
Geonet statistics over the past year reveal that the larger Canterbury region and the South Island in general are the most seismically active over the period, but the Wellington and Taranaki regions now have prominence in the North Island statistics.
While Christchurch itself has been seismically quieter, activity in the larger region has implications for the city
Geonet stats.
July 29 2013
Christchurch has today felt the effects of a M4.7 south of Hanmer Springs.
The Seddon Sequences are capable of stressing the Alpine Fault and recent activity in Canterbury has tended to be more north and west
for more on the Alpine Fault issues - video of recent research
July 22 2013
Data has been removed from Quakemap related to the graphic below suggesting false readings.
Peak ground acceleration in the newly named Seddon Sequences measured in respect of gravity was only 10% of the strength of shaking experienced in the Feb 22 Chch quake. [20%G vs 2G]
No events over M4 of late in the Canterbury region
July 21 2013
Cook Strait activity has increased since July 19 [M5.7]with 2 larger events on this day - M5.8, M6.5
Christchurch has not been unconnected to this significant seismic activity.
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| quaklive data |
July 19 2013
Quakes approaching M4 have been occuring in the larger Canterbury area in the past week -latest July 19 M3.94 , shallow 5kms deep inland hill country near Bealey at 12.13pm.
This follows and most likely a resonant response to the most significant recent quake in NZ earlier, same day, further north: M5.7, 16kms deep, seafloor east of Seddon at 9.06 am.
Multiple aftershocks followed in that location, the highest being M4.5, then 3 between M3.3 - M3.5
July 17 2013
A resumption of stronger quake activity in the period mid June-Mid-July after a lull mid-May to mid-June -see Quakelive
June 18 2013
Important insights and writings of Fiona Farrell on the Christchurch aftermath, from Radio NZ interview, June 16
This snapshot of activity since 2007 gives some insight into the extended strength of activity
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| Quakelive graphic showing 50kms radius of Chch central |
May 2013
A pattern of intermittent events over M3.0 and up to M4.16 - along with sporadic lower magnitude aftershocks continues across the region
April 2013
Alpine Fault study sees Canterbury at risk of M7.0 effects - report
The most recent 25 events March 27-April 9 -from M1.9 to M3.0
Coloured dots show variable depths. Though intensity & frequency have declined, recent activity is diverse across the region -north-south-east-west as shown on this clickable graphic from Quakemap
March 2013:
Early in March, especially March 5-10 saw a slump in seismic activity in the target region but following a geomagnetic storm [ the magnetic disturbance on earth after the sun discharged a full halo coronal mass ejection on March 15] St Patrick's weekend's magnetic sudden impulse would be expected to show some subsequent seismic disturbance in vulnerable regions - and it did on March 18 across Canterbury with a resumption of lower level events under M3 in diverse places west to east, so there may be more potential building for a larger aftershock.
February 2013:
In the fortnight from late January 2013 to early February an uptick in quake energy is evident in energy graphs supplied by Quakemap & Quakelive.
The following updates prior to 2013 were added to original post of June 13 2011
An end of 2012 summary and a dedicated 2013 post are now available on this site for more current information on Canterbury and Christchurch earthquakes and aftershocks. further reading includes Christchurch: why warnings have been given
September 21 2012
Recent event over M4 -Sept 21 M4.3
In recent months, the region had reached the longest period of inactivity/minimal seismicity since the Sept 4 2010 initial sequence. see July-August 2012 data
Seafloor events in Pegasus Bay continue to dominate
July 11 2012
July has seen two large but undamaging quakes a M4.88 at Greendale fault zone on July 6 and a M4.94 on July 10 at Tai Tapu. These fall within the 6 month warning period but July remains a vulnerable period re further significant unrest.
June 2 2012
M4.3, 9kms deep this morning, seafloor off Sumner, adding to recent M4+ activity in Pegasus Bay
May 31 2012
South Canterbury has produced a strong, 100 tonne, M4.5 shake this morning [ with aftershocks], centred at Mayfield, west of Ashburton and described as "savage" in Temuka -report
May 28 2012
The Pegasus Bay seafloor is hogging the higher magnitude action currently with M3.9 & M4.4 both at 8kms deep this morning
See Quakemap [this specific data link will expire in days] .
The energy graph is climbing in a manner not seen in the prior 3 sequences
May 25 2012
Diverse seismic activity on land and undersea, to a maximum of M5.2 - which was offshore of New Brighton. 13 quakes over M2.0 reported up to 6pm today.
Geonet graphic: showing the most significant activity since January 2 2012, subsequent to the sequence starting on Dec 23 2011
Even the govt acknowledges that each quake of significant magnitude makes insurers more nervous & the rebuild more delayed. Insurers want a clear time frame of nil to little seismic activity in order to take a punt on Christchurch, because they are not in the business of paying out.
[update May 28: insurers claim it's business as usual - report
May 23 2012
In terms of the broader seismic condition of the South Island, recently published research has focussed on readings taken 100kms underground in a 50kms section relating to the Alpine fault - from Karangarua River in the southwest, to Whataroa. Two years of data were collected relating to unusual "creeping" or "rumbling", slow-slip, long-duration quakes - not short, sharp discrete events as commonly known - but low intensity -around M1.0 level readings lasting minutes, weeks and years. This situation remains unclear as to whether it is a build-up or a release situation relating to the Alpine Fault -but researchers acknowledge that the region is overdue for a top magnitude quake - M8.0 or higher, as has happened there on 4 occasions in the past 900 years ( the last being around 300 years ago) GNS Science rates a high probability of a major Alpine quake in the coming 40years, which will have extensive human impact. - full report
May 21 2012
Press report on the flurry of quakes on May 20
Quakelive recorded 17 shakes in 24 hrs.
This quake sequence has retained considerable vigor, in terms of the bounce back capacity at this point of supposed decay. Don't rule out more surprises.
May 20 2012
6.18pm update
M4.8 seafloor quake, 5.06pm, seafloor off Sumner, 8kms deep. No damage or outages reported
Earlier report:
The seismicly sensitive Rolleston tip of the Greendale fault has been active this morning, producing a M4.1 quake, 10 kms deep at 9.35 am. The Rolleston area features significantly in the top 100 quakes of Canterbury since Sept 4 2010. The current Top 100 ranges from the initial M7.1 down to M4.63 - data
Update & correction : The M4.8 has now entered the Top 100 at spot 71.
Top 100 positions 13, 26, 40, 44, 53, 69, 76, 91, 93 (9 events) all occurred in January 2012, so today's quake means 10% of the Top 100 have occurred within the first 6 months of 2012
Noting that this coincides within the effective period of an annular solar eclipse [exact on May 21 NZ time].
May 16 2012
Superimposed graphics using original energy data from Quakelive
Comparisons may show pattern similarities. Of the 6 comparisons, June and December 2011 appear to be following the most similar decay pattern. (click any graphic to view in slideshow panel)
     
May 15 2012
Pegasus Bay quake today at 1.27pm - 10kms deep, 6.6kms off New Brighton.
Being 52 tonnes, this is the largest since a swarm over M4 in January 2012
The M3.3 ( 1 tonne) which followed it, at 1.48pm was on land in the Landfill Ave-Waitikiri Golf Course area, north east of the city.
May 14 2012
Data provided by Quakelive covering 4 sequences of quakes since Sept 4 2010 in Canterbury-Christchurch gives the following comparisons of length of sequence, using basic analysis of their data where 30.5 days = one month.
Sept 4 : 5.6 months
Feb 22 : 3.6 months
June 13: 6.3 months
Dec 23 : 4.7 months to date
What happens over the next 8 weeks may indicate whether this last sequence shows any consistency with the prior 3.
April 12 2012
Was a resonance response involved in the M4.6 quake in Pegasus Bay 12 noon today? ([the largest since Jan 27 2012 in the region]
The Christchurch event shown above on the Geonet quake drum
This comes at noon on April 12 NZ time, about 16 hours after the waters off Sumatra Indonesia shook to repeated quake sequence initiated by a M8.6 in the Indian Ocean - which registered like this in New Zealand:
The Sumatra M8.6 at around 8.30pm NZ time April 11 registers strongest on the northern quake drums.
Mexico has also had a significant quake equivalent to 10.55am NZ time on April 12
April 7 2012
Though Pegasus Bay has hogged the limelight in terms of persistent quake activity since Dec 23 2011, now some higher magnitude activity has resumed at the Greendale fault area around Rolleston ( April 6 M3.86, M4.19) The latter is the largest since M4.29 March 18 2012, east of Lyttelton
March 26 2012
The desolation of many neighbourhoods in Christchurch (examples examples) reflects a global phenomenon of emptied and abandoned spaces -see image gallery
March 24 2012
2 simultaneous Pegasus Bay quakes Christchurch M3.9-M4.1 at 5.09pm local timecontinue a spate of nationwide events over M4.0 during March, coinciding with intense solar activity and subsequent geomagnetic intensification. This is consistent with the proposal that earthquakes may be precipitated in response to elevated solar phases - read more
March 18 2012
Latest 25 as at 10.51 am: The pattern has resumed an "all over the place" scatter situation indicating widespread movement. Colour dots equal depths with hot colours being most shallow.
Latest 25 - click to enlarge all graphics - source Quakemap
Two M4 events around 1am this morning Banks Peninsula area recorded on Quakelive (other sites say just a single M4.3 or M4.4 event).
March 1 2012
A M4.3 quake at Rolleston, in the Greendale fault zone at 8.02 am today, preceded by small local movements in the Rolleston-Prebbleton-Lincoln triangle, while most activity continues in Pegasus Bay. Today's quake is second largest since Feb 8 and the 3 largest in that time frame have been in 3 different locations - west, Pegasus Bay and Banks Peninsula.
The vigorous, though declining, pattern, activated since Dec 23 2011 is visible on this energy graph
The Feb 22 anniversary was charitably quiet during memorial services.
Strongest and most frequent activity is now back in Pegasus Bay since Feb 19
click images to enlarge
February 9 2012
The most recent pattern is away from Pegasus Bay and back to the mainland, with a quake swarm around the February 8 Full Moon
M4.2 and M4.3, M3.5 on Banks Peninsula (Feb8-9)
M4.2 Rolleston South (Feb 9)
M3.2 Bromley (Feb 9)
Latest 25 on Jan 22 CHCH QUAKEMAP
click images to enlarge
January 27
Confirming the report noted on Jan 25, after some noise several hours earlier, on the Oxford quake drum, a M4.6 quake occurred in the Greendale zone near Rolleston this evening
The Geonet NZ quake drum shows the M4.6 emerging around 8.45 pm Jan 27
January 25
Scientists have released an opinion re renewed seismic activity at the Rolleston area of the Greendale fault zone
"stress still needs to be released" -full Press report
January 23
Left,right and centre. Significant seismic action in the west, centre and east continues
M4.5 in Pegasus Bay is the largest
January 21 2012
This day was notable for a resumption of significant quake activity ( including two M4+ ) at the Rolleston end of the Geendale fault in west Canterbury
Meanwhile, the feisty forces operating in Pegasus Bay show a vigorous sequence extending since Dec 23.
January 10 2012
Updated entries on Mathematics Link Christchurch Quakes shows how powerful the December 23 new Pegasus Bay sequence is. This new sequence may provide a big clue to the next significant phase.
 CLICK TO ENLARGE ALL GRAPHICS 
January 6 2012
The Quakelive energy chart shows how strong this sequence is compared to the June 2011 events.
Today M5 Pegasus Bay. Council plans to install a tsunami alert system and seismologist Kelvin Berryman does not rule out a quake induced tsunami; "around Canterbury there may well be an ongoing sequence over a period of a few decades". Kelvin Berryman tells meeting today -more from The Press
January 4 2012
Christchurch Quakemap graphic of top 25 quakes (2010-2012) shows a range from M5.2-M7.1. In 2012 this includes already a M5.5 in Pegasus Bay Shakes in the M2-M3 range continue -almost exclusively in Pegasus Bay. Seismic research from Switzerland uncovers information of value to those in Christchurch: liquefying soils amplify quakes January 3 2012
Christchurch Press is reporting :
"United States seismologist Kevin Furlong, a visiting professor at Canterbury University last year from Pennsylvania State University, said all the quakes since December 23 were similar, produced by slip on short, steeply dipping faults oriented roughly east-northeast/west-southwest". "The magnitudes of the events are not particularly alarming, but what is of particular interest is that we are having something that is more swarm-like; that is, a multiple number of similar-sized events in a region, but not all on the same structure or fault." - FULL REPORT Residents of Christchurch are wanting answers since the eastern seafloor location raises concerns of swells or a tsunami being generated in the bay by a M7+ event. Scientists will meet this week under urgency to discuss what may have generated this recent swarm. For alternative views on the risk potential go to Christchurch - why warnings have been given. January 2 2012
A second swarm today, commencing 1.27 am, comprising over 3 kilotonnes of energy release, with magnitudes up to M5.48 so far by 8.14pm, all in Pegasus Bay, clustering off New Brighton but also further north and further east, broadening the geolocation of the events. This is a major sequence.
Click to enlarge all graphics: above Geonet NZ Jan 2 2012 screenshot
Dec 26 2011
This news cannot have been of any reassurance to Chch-Canterbury residents that they are safe from significant environmental threats.
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| Google Map from Quakelive Shows Pegasus Bay with marked faults known prior to Dec 2011
The majority of quakes in this sequence have clustered around close offshore from New Brighton where the purple quake marker sits in this screenshot. The most northern one was at the latitude of Sefton and around centre longitudinally in this image. The most southern seafloor event has been north of Diamond Harbour. Significant land-based quakes have also occurred in the area marked as Diamond Harbour
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| Click to enlarge
In this latest sequence, targetting Pegasus Bay, data taken from the period from 1.58pm Dec 23 2011-11.44am Dec 26 2011 over 27 kilotonnes of energy has been released into Pegasus Bay. (kilotonne=1000 tonnes)
The initial event released 9 kilotonnes
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Dec 23 2011
Major quakes today in Christchurch M5.8 at 1.58pm plus significant aftershocks
Dec 23.2011 News Report
Initial data received on Dec 23 2011:
Dec 16 2011
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| click to enlarge Geonet graphic |
Dec 23.2011 News Report
Initial data received on Dec 23 2011:
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| USGS data gives 3 quake events
QuakeMap now listing 5 events over M4 this afternoon Dec 23
M5.9,M5.3 M4.6 were all seafloor events Pegasus Bay off New Brighton
at 3.18pmThe M6 was on the shore at South New Brighton
at 4.50pm The M5 was again in Pegasus Bay
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Dec 16 2011
A downtrend has continued in quake frequency in Christchurch - see data page but the lives of many residents are still in limbo and the recovery of the region has been slow -read an end-of-year summary
November 20
Rev Mike Coleman, On Behalf of WeCan! (Wider Earthquake Communities Action Network)
and the many Cantabrians who are struggling to be heard, has published a plea for all New Zealanders to listen to the plight of those affected by the quakes.
Though the media have largely gone away, the suffering has not - here is an extract:
We would like to know what is really happening to the people of Canterbury. What you have been led to believe is not the reality for thousands of Cantabrians. There has been dishonesty in the way the
Government has portrayed their handling of people affected by the earthquakes. They are not telling the truth.
There were never 11,000 sections ready for more than 5,000 displaced households as stated by Mr
Brownlee on a street corner in June. There is no affordable land in Canterbury for many of these people.
Our Government, on your behalf, are forcing thousands from their land with no hope of being able to
purchase new land. This will become another dark reality in our history and we are the generation
allowing this to happen. FULL DOCUMENT
November 2011
November 9 After days of nil activity, now in the full moon phase, quake activity has come alive again with the largest being M4.2 west of Coopers Creek. At least 29 tonnes of energy release in that region of west Canterbury. ENERGY GRAPH
November 20
Rev Mike Coleman, On Behalf of WeCan! (Wider Earthquake Communities Action Network)
and the many Cantabrians who are struggling to be heard, has published a plea for all New Zealanders to listen to the plight of those affected by the quakes.
Though the media have largely gone away, the suffering has not - here is an extract:
We would like to know what is really happening to the people of Canterbury. What you have been led to believe is not the reality for thousands of Cantabrians. There has been dishonesty in the way the
Government has portrayed their handling of people affected by the earthquakes. They are not telling the truth.
There were never 11,000 sections ready for more than 5,000 displaced households as stated by Mr
Brownlee on a street corner in June. There is no affordable land in Canterbury for many of these people.
Our Government, on your behalf, are forcing thousands from their land with no hope of being able to
purchase new land. This will become another dark reality in our history and we are the generation
allowing this to happen. FULL DOCUMENT
November 2011
November 9 After days of nil activity, now in the full moon phase, quake activity has come alive again with the largest being M4.2 west of Coopers Creek. At least 29 tonnes of energy release in that region of west Canterbury. ENERGY GRAPH
November 4 Seismologists have issued a higher probability 12 month forecast for Canterbury - as the region may be subjected to "an extended aftershock cluster". A clearer picture on that probability will reveal itself within the coming 6 months. New % forecasts are:
M5.5 - 5.9 - up from 37 %. to 46% in the next year
M6.0 - 6.4 - up from 10% to 15 % in the next year
The change is due to favouring a more unusual pattern over the standard model
The change is due to favouring a more unusual pattern over the standard model
October 29 Seismic activity has been in the lower range since a significant eastern seafloor release of 2 kilotonnes on October 9. Recent highest activity has not exceeded 9 tonnes - energy graph
October 22 Christchurch (Rolleston) resonates with a M3.8 in hours following M7.4 seafloor shake, Kermadecs region near Raoul Island this morning, 6.57 am, as happened with the last M7+ quake in the Kermadecs in July 2011
October 18, 2011 An ever changing dispersal pattern of aftershocks prevails - "left , right & centre".
The Royal Commission into the quakes is in process. The geoscientific evidence is that a quake in the region of M6.0 has a 14% chance of occurrence in the coming year.
Having said that that faults that ruptured have reduced stress for some time to come, Dr Pettinga says other unknown faults could rupture: "We don't have the complete picture" he says.
This would not fill me with confidence. If another fatally destructive quake does arise in the next year, the geoscientists always have an out clause with these statements.
Again, locals need to consider how much risk they are prepared to live with and make life plans accordingly. No government agency will now take any level of accountability if a worst case scenario occurs again in the Canterbury region. This perception is reinforced by the withdrawal of insurers from a place of such high risk.
October 9 2011 The significance of the October 9 quake is evident on this energy release graph
The Geonet reading is below. Aftershock intensities continue to exceed average forecasting
Activity is occurring left, right & centre in the region with the current emphasis strongly in the eastern hills-seafloor, after a period around the Greendale fault zone.
Activity is occurring left, right & centre in the region with the current emphasis strongly in the eastern hills-seafloor, after a period around the Greendale fault zone.
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| October 9, 8.34pm M5.5 = 2 kilotonnes (8th largest) 12kms deep, seafloor off Boulder Bay |
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| October 8 2011sequence begun with M4.8 at 4.17pm data from Geonet NZ |
From 4.17pm a sequence of 8 shocks in the Pigeon Bay area of Banks Peninsula, the largest two being M4.8, M4.1
Over 246 tonnes of energy released between 4.17-4.56pm in various sites in the hilly area of Pigeon Bay where elevation averages hundreds of metres.
Three of the quakes were under 5kms deep.
Over 246 tonnes of energy released between 4.17-4.56pm in various sites in the hilly area of Pigeon Bay where elevation averages hundreds of metres.
Three of the quakes were under 5kms deep.
Animated events on QuakeMap
JUNE 2011
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June 13 2011 Geonet quake drums seismograph |
This morning a posting re the eclipse sequence we are in during June 1-July 1 - a triple sequence of 2 solar and one lunar which ramps up the geophysical stresses. Added to this the moon was as perigee -closest orbit on Sunday 12th and the next eclipse will be exact in NZ on Thursday 16th. These factors have an impact on the integrity of the earth, due to push-pull forces.
the following prior posts have focussed on Christchurch in particular, date back to March this year (2011)
Christchurch Quake Warnings
Recent quake data
Christchurch: why warnings have been given
Update 3.21 pm
The aftershocks total 13 with high magnitude 4.3, 4.4,4.9, 5.5 and M6.0 in the past 3 hours
Can anyone explain this synchronicity:
Trigger event on 4th ( Sept 2010)
Second event on 22nd ( February 2011)
Third event on 13th ( June 2011)
A numerologist would point out that all reduce to the number 4 and the themes of these events are extremely reflective of the problematic energy of 4 due to its resonance with the principles of Saturn
Update June 14
Anyone interested in mathematics may appreciate the newer post on links between the 3 main Christchurch events and how they have a connection to the last lunar eclipse.
Also noting that :
Sept 4 event was 4 days before the New Moon & lunar perigee ( closest orbit to earth) for that month
Feb 22 event was 3 days after Full Moon and lunar perigee
June 13 event was one day after lunar perigee and 3 days before Full Moon lunar eclipse
33 aftershocks today have hammered east Christchurch as at 7.08pm. The total will increase before midnight. (this data will only have a duration of one week from posting) So far today the highest M4.7 at Buckley's Bay Reserve was also the deepest at 13kms.
Mostly eastern coastal hills and the seafloor are being boomed as if by an unseen underground artillery.
Yesterday, June 13 there were 51 quakes ( the largest were upgraded to M6.3 & M5.6) showing overwhelmingly a similar locational preference.
Geoscience has concluded that a NEW fault has occurred in the June 13 events
The Daily Release chart - of quake energy - is also worth a look
Geonet's forecast for this month to June 18 in terms of averages, has already been far exceeded, following a quietening, slowing and down-trending period, mid March to mid April. From April 19 their data reveals an uptrend.
Some data may be subsequently upgraded by Christchurch Quake Map after release & publication.
Update June 16
By 6pm a very high number of aftershocks, (34) with several sizeable magnitudes - with 5 over M4.0
In comparison, on June 13 the new sequence date, there were 8 fore or aftershocks of M4.0 or higher. The Angry Earth just isn't settling according to standard modelling. Daily event totals so far : 67, 51, 34 -from June 13-June 15. Activity has become intense in the Banks Peninsula area, which is an ancient volcanic zone.
http://bit.ly/hDz2ek
Update June 22
Activity has shifted from primarily Banks Peninsula to the Halswell-Lincoln area in the west on June 21. The highest mag of that day was M5.4 in this area. The current Daily Release of energy chart
This summary this morning in The Press talks of anomalous aspects to the June 21 activity
shows June 23 data with a horizontal cluster aligned with the Greendale fault. If that line is taken west to east there are 13 of the 16 aftershocks in that zone
Update June 29
Update June 23
This summary this morning in The Press talks of anomalous aspects to the June 21 activity
Update June 24
Christchurch Quakemapshows June 23 data with a horizontal cluster aligned with the Greendale fault. If that line is taken west to east there are 13 of the 16 aftershocks in that zone
Update June 29
A lull on June 28, only 2 aftershocks, but increasing today with multiple activity in/around Lyttelton Harbour
The Christchurch Press Ask an Expert (geoscientist column) is worth looking at: the question re tsunami potential is particularly worth having an understanding of. Pity that the local council is offering housing subdivisions in Belfast.
Update July 2
Update July 2
Some earthquake science including elastic rebound theory
9,2,10,4,7,2,1...and today, so far 0. This is an unusually quiet lull and with the gravitational factors high from July 1, the week ahead, including lunar perigee on July 7, will be one to watch in terms of a rebounding uptick, as evidenced after prior lulls, on the university graph.
A powerful southern ocean low about to impact NZ for an extended wet, windy & cold winter storm will add atmospheric turbulence into the mix - watch and see if this factor appears to play a role in a seismic uptick. There are people who subscribe to this theory.
Global statistics for the past decade show M4.0-4.9 is the most frequently occurring range globally. Following that are the bands from M. 3, then 2, 5, 1, 6, 7, and finally M8.0-8.9 - source USGS
Update July 8
Canterbury Quake Live is also an excellent site for extra detail, graphs, data, maps.
July 7 saw a M4.4 in the Oxford area which is an expected uptick (largest since M4.4, June 27) after the lull between June 30 and July 4 inclusive, when daily totals were 4,7,2,2,5 aftershocks.
Geonet map of past 60 days
The rich aftershock pattern noted by Geonet continues, with the June 13 events (M6.3, M5.6. The Daily Energy Release graph shows how strong this recent sequence is even though events are far less frequent. (this link will alter over time, but look for early July data)
GNS Science has updated computer-generated quake forecasts for the Canterbury aftershock zone, saying there is a 23 per cent chance of a magnitude-6.0 to 7.9 quake in the next 12 months.
If that does not happen, that will fall to a 20 per cent chance on August 15 for the subsequent year, and, similarly, to 18 per cent on September 15 for the following 12 months.
The probability of a magnitude-5.0 to 5.9 in the next year remains high, at 94 per cent.
New faults found "There's multiple hidden fault structures." "We need to be careful and cautious".-
Update July 17
Full Moon event period July 13-17 - significant clusters or events data (USGS)
M4.4 July 16 Chch
M4.0 July 17 Chch
M5.0-5.2 - 7 events Kermadecs region
M5.0-5.2 - 4 events Honshu, Japan
M6.0 Chile
M6.1 Alaska
M5.3-5.9 - 3 events Tonga region
Translating the long-term Geonet forecasts:
90% chance in the period Mid July 2011-mid Sept 2012 of a quake in the range M5.0-5.9 in Christchurch.
25%, declining to 20% chance, in that time frame, of a quake larger than M6.0
Update July 4
A lull period in global seismicity in terms of events over M6 globally ( last being June 26 M6.3 offshore Indonesia) and in Christchurch NZ, daily aftershock totals plunging in this recent sequence from Monday June 27:9,2,10,4,7,2,1...and today, so far 0. This is an unusually quiet lull and with the gravitational factors high from July 1, the week ahead, including lunar perigee on July 7, will be one to watch in terms of a rebounding uptick, as evidenced after prior lulls, on the university graph.
A powerful southern ocean low about to impact NZ for an extended wet, windy & cold winter storm will add atmospheric turbulence into the mix - watch and see if this factor appears to play a role in a seismic uptick. There are people who subscribe to this theory.
Global statistics for the past decade show M4.0-4.9 is the most frequently occurring range globally. Following that are the bands from M. 3, then 2, 5, 1, 6, 7, and finally M8.0-8.9 - source USGS
Update July 8
Canterbury Quake Live is also an excellent site for extra detail, graphs, data, maps.
July 7 saw a M4.4 in the Oxford area which is an expected uptick (largest since M4.4, June 27) after the lull between June 30 and July 4 inclusive, when daily totals were 4,7,2,2,5 aftershocks.
Geonet map of past 60 days
Update July 14
The rich aftershock pattern noted by Geonet continues, with the June 13 events (M6.3, M5.6. The Daily Energy Release graph shows how strong this recent sequence is even though events are far less frequent. (this link will alter over time, but look for early July data)
Update July 16
The official line, earlier this week is contradictory: that things are quietening plus high magnitude events are likely, according to this report (source The Press):GNS Science has updated computer-generated quake forecasts for the Canterbury aftershock zone, saying there is a 23 per cent chance of a magnitude-6.0 to 7.9 quake in the next 12 months.
If that does not happen, that will fall to a 20 per cent chance on August 15 for the subsequent year, and, similarly, to 18 per cent on September 15 for the following 12 months.
The probability of a magnitude-5.0 to 5.9 in the next year remains high, at 94 per cent.
New faults found "There's multiple hidden fault structures." "We need to be careful and cautious".-
Full Moon event period July 13-17 - significant clusters or events data (USGS)
M4.4 July 16 Chch
M4.0 July 17 Chch
M5.0-5.2 - 7 events Kermadecs region
M5.0-5.2 - 4 events Honshu, Japan
M6.0 Chile
M6.1 Alaska
M5.3-5.9 - 3 events Tonga region
Translating the long-term Geonet forecasts:
90% chance in the period Mid July 2011-mid Sept 2012 of a quake in the range M5.0-5.9 in Christchurch.
25%, declining to 20% chance, in that time frame, of a quake larger than M6.0
Update July 18
Check out the broader Canterbury seismic drums. Inchbonnie (Alpine Fault) has acted up twice in 24 hours with lots of noise but no magnitude event
Update July 22
The Geonet NZ seismograph for the M5.1 today 5.39 a.m. at Dunsandel. See the regional drums
Geoscientist's latest forecasting which includes far more detailed breakdowns of their computer modelled expectations. The Wild Card in all this of course that a new hi-mag event sets off a newly energised sequence. Today's event is in the Greendale fault zone of Sept 4 2010. It has been assessed by Canterbury Quake Live as the 19th equal highest mag since Sept 4, shared with 6 other events, but the deepest of that set, at 11.7kms.
Update July 23
The Canterbury pattern seems to have shifted to one of infrequent but high magnitude events, whereas the previous sequence declines since Sept 4 went into extended lower magnitude batches of M2+ and M3+.
Today's M4.3 11kms deep, 7.45 a.m., was again in The Dunsandel area of the Greendale fault.
Data can be searched.
Compare the two M6+ sequences, first starting February, showing highest magnitudes.
1. Feb 22 sequence is 6.46, 5.08, 4.94, 5.32, 5.22, 5.31, 5.55
2. June 13 sequence: 6.37, 5.46, 5.09,Check out the broader Canterbury seismic drums. Inchbonnie (Alpine Fault) has acted up twice in 24 hours with lots of noise but no magnitude event
Update July 22
The Geonet NZ seismograph for the M5.1 today 5.39 a.m. at Dunsandel. See the regional drums
Geoscientist's latest forecasting which includes far more detailed breakdowns of their computer modelled expectations. The Wild Card in all this of course that a new hi-mag event sets off a newly energised sequence. Today's event is in the Greendale fault zone of Sept 4 2010. It has been assessed by Canterbury Quake Live as the 19th equal highest mag since Sept 4, shared with 6 other events, but the deepest of that set, at 11.7kms.
Update July 23
The Canterbury pattern seems to have shifted to one of infrequent but high magnitude events, whereas the previous sequence declines since Sept 4 went into extended lower magnitude batches of M2+ and M3+.
Today's M4.3 11kms deep, 7.45 a.m., was again in The Dunsandel area of the Greendale fault.
Data can be searched.
Compare the two M6+ sequences, first starting February, showing highest magnitudes.
1. Feb 22 sequence is 6.46, 5.08, 4.94, 5.32, 5.22, 5.31, 5.55
(this will be updated as data arrives) Feb 22 started with a slightly higher, though the most destructive due to location, but the June 13 set is followed so far by higher magnitude events.
Update Aug 2 2011
Fun fact: Feb 14 2011 saw a major X-class solar flare send pulsing magnetic material towards earth. Nothing that significant had been recorded by NASA since 1995. Of late the sun has been extra quiet ( see post on Solar minimum & sunspots) but the odd large flare is still in the frame.What we know is Christchurch & Japan suffered extreme quake damage within a month of that event.
Currently amidst a flurry of sunspots across the sun's mid-latitudes, Sunspot 1261 is believed to harbour capacity for another X-class flare. Watch and see what August brings. Christchurch has been very quiet of late though, as if tailing off ( July 22, M5.1 is the last high mag event) View some Chch quake history - graphed
Update August 26
An at a glance look at the quake progression since Sept 4 2010 in Chch/Canterbury shows events are at a similar point to May 2011, still with potential for a M5+ event. Mid June to mid July was the most active recent period and the present period continues at an average/below average event level.
For those who follow Ken Ring -his observations are pointing to caution needed, particularly around late Sept.
My references show a higher gravitational period from Sept 23-30 involving solar and lunar factors, with 27-28th particularly energised by the alignments of Mercury, Mars, Uranus and Pluto. People and places corresponding ( by vibrational resonance) to the turbulence generated will experience difficult/stressful events, but I will leave that to other locational specialists to determine whether Christchurch is in the frame. Certainly people born, any year, on or close to, Sept 27, Dec 26, April 24, July 25 are the prime resonators.
Update Sept 1 2011
After a lull period in August, the end of the month August 31 saw two higher intensity events: M4.0, M4.7 (or .8 in one source) The energy graph shows August 31 was the biggest seismic pulse since July 22 (highest M5.1)
Update Sept 2
Locals will be nervous in the light of the 3rd M4+ event on the eve of the Sept 2010 M7.1.
Today, Geonet reports:
This event conforms to a commonly seen pattern: 4 days after New Moon as well as in close proximity to perigee (Aug 30) , Moon at equator (Aug 30).
