Much as we are shocked by recent city seismic catastrophe, knowing what to expect next would soothe nerves and add hope in eventual recovery. This begins by realising that there is no level or agency of government – central or local, executive or public service – exercising precautionary principle and over-seeing our collective well-being here. That responsibility is all our own.

Christchurch Quake Energy - Crowe.co.nz 030711

Christchurch Quake Energy - Crowe.co.nz 030711


The graph http://quake.crowe.co.nz/QuakeEnergy can show us how soon to expect the next Christchurch 6+ earthquake, should there be one, by observing energy conditions between the previous three. Viz:

Local earthquakes:
# 1. 4 September 2010, magnitude 7.1 ; # 2. 22 February 2011, 6.3 ; # 3. 13 June 2011, 6.3. [1]

Line X. is the 10-Gigajoule average daily energy-release marker: once daily aftershocks have fallen into this zone then the conditional driver for the next Christchurch 6+ earthquake is here.

Historic points A. and B. on line X. indicate where point C. is heading to in the near future – averaging ten gigajoules of aftershock daily energy release – which will shortly precede the next Christchurch 6+ earthquake, most likely, based on the local quake pattern to date.

Of course the number of aftershocks are tailing off over time, as shown by Crowe’s green bars. This can be deceptive, however, given these faults’ rock type and its reported ‘stickiness’ – a propensity to release friction in big, uneven jolts rather than smoothly. Hence community concern at the current seismically quieter period.

But the steady tailing off of aftershocks is what the geologist experts’ mathematical modelling has consistently predicted, so we can draw a measure of comfort from that. Their view that the ancient volcanic crater around Lyttelton Harbour / Te Whaka-raupo is absorbing shocks within its many concentric cooling faults seems real and reassuring. The fact that these analysts were entirely wrong in not foreseeing the second and third local main shocks, however, gives us every reason to extend public-good quake analysis by way of commentary such as this blog and community discussion. It honours those lost, by warning those still here who may face further civil emergency.

Extra info: Canterbury earthquake GNS Science media release:

Aftershocks-map-27-06-2011 GNS Science

Aftershocks-map-27-06-2011 GNS Science

The clustering of aftershock phases in three bands, west to east and following the three main shocks, is colour coded here by GNS Science; will there be a fourth? The accumulated stress beneath the Port Levy / Pigeon Bay area – coloured blue at south-east – may well indicate this as building the next 6+ fault-break location.

Canterbury Quake Energy - Crowe.co.nz 050711

Canterbury Quake Energy - Crowe.co.nz 050711

Updating the latest Crowe Quake Energy chart, line X has almost been converged upon: daily fault-energy release is still averaging just above ten gigajoules (approx), giving us a matter of days/hours before the next 6+ local earthquake, by this already-proven forecast mechanism, if there is to be another one.

Stay strong. Watch Chris Crowe’s graph.

~ Kia ora

[1] Ref. geonet.org.nz
# 1. Magnitude 7.1, Saturday, September 4 2010 at 4:35 am (NZST), 40 km west of Christchurch
# 2. Magnitude 6.3, Tuesday, February 22 2011 at 12:51 pm (NZDT), 10 km south-east of Christchurch
# 3. Magnitude 6.3, Monday, June 13 2011 at 2:20 pm (NZST), 10 km east of Christchurch

Bingo: Magnitude 6.5, Tuesday, July 5 2011 at 3:36 pm (NZST), 30 km west of Taupo
Unfortunately this ‘near miss’ for ChristChurch is not good news, for we share an integrated tectonic system and highly-connected local earthquake effects :-/ ..: Taupo 6.5 quake not good news 4 ChristChurch or NZ

Taupo magnitude 6.5 - GNS Science 050711

Taupo magnitude 6.5 - GNS Science 050711

Update 16 July 2011
Very interesting how the Taupo magnitude 6.5 of July 5th reset the Canterbury seismicity level upwards for the following two weeks:

Quake Chart Energy - Crowe.co.nz 160711

Quake Chart Energy - Crowe.co.nz 160711


Point A shows the daily quake energy level that had declined, to the critical 10-Gigajoule mark “Line X” – until 5 July.
Point B shows how close we are to that aftershock decay level again now.

Advertisements