Vagueness tainted with profit-driven caution flavour official reponses to
ongoing earthquake trauma in Christchurch:
"Shocks may be last gasp of Feb 22 fault" says The Press -
http://www.stuff.co.nz/the-press/news/christchurch-earthquake-2011/6208949/Shocks-may-be-last-gasp-of-Feb-22-fault
- really?
Why has it taken SIXTEEN MONTHS for top earthquake specialists to start
looking in the right direction - East? Could this be revelatory of systemic
flaws in social privilege and academic hierarchy, producing intellectual
indifference? Quote 1:
"GNS Science natural hazards platform manager Kelvin Berryman said
yesterday that one theory was the Port Hills Fault, or splinters of it,
were responsible for the aftershocks hitting the city since December 23.
'I'm sort of comfortable in thinking this could be some residual activity
from the eastern end of the February 22 fault that didn't rupture all the
way out there,' Berryman said. 'We did see that there was a small patch of
that fault that does go offshore that may not have had much activity until
lately.' The 'patch' had been 'very productive' in generating aftershocks
since the two big quakes on December 23, he said. 'These 5.5s are pretty
substantial but only a quarter, or a third, of the energy of the 6.0 you
had,' he said. Berryman said GNS Science researchers would work this week
to come up with some answers on what was causing the swarm of quakes."
WHY was so much resource committed, so early, in the opposite and wrong
direction ?!? - see
http://www.chcheqjournal.com/2011/focus-network-hidden-faults/ of July
2010.
Quote 2:
"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.' Stress modelling for the
September 2010, February and June 13 quakes showed the area east of the
city had experienced a small increase in stress supporting quake behaviour,
Furlong said. 'The stress changes are relatively small. They in themselves
don't cause the earthquake,' he said. 'But if a region [silo thinking] is
suitably stressed prior to the stress change, then these small amounts of
stress change can advance or trigger the subsequent events. 'Basically, the
situation that Christchurch finds itself in is a region β and by this I
mean the entire region surrounding the city β that was suitably stressed
prior to the September event, and since that time we have seen a sequence
of events that pretty much follow the patterns of where stresses were
slightly increased by the September event. 'What has controlled the actual
space-time pattern of events is not totally clear, but in general it has
been pretty much an eastward march of earthquakes.' Some 'good news' was
that each of the big quakes appeared to be acting independently, he said.
'When the February event occurred, it did not reinvigorate the Greendale
Fault. Similarly, the June event did not reinvigorate either of the two
previous faults, and the recent suite of events has not really lit up any
of the previous regions, including the June rupture," he said. 'It seems to
indicate that each event is effective in reducing the stresses on its fault
such that they are no longer in a triggerable situation.' [? - 22-23 Dec
small Greendale quakes triggered the 6.0!] Some 'good news in all of this
is that the activity is moving east. 'After the June event, since it was on
a structure of different orientation β more north-south β it was unclear
whether the behaviour was changing. These events seem to indicate a return
to the slow but sure eastward march. [That overriding prognosis was already
obvious by October 2010 and should never have been derogated; it was
documented here: http://www.infohelp.co.nz/quake.html -
http://www.infohelp.co.nz/pix/200111-CQL-CHC-Screenshot-8x6.png ] 'None of
this really will make Cantabrians feel better about things, but what makes
this a bit intriguing is that it has continued in such a systematic way for
so long. I guess my arm-waving explanation is that the entire region was
sufficiently stressed, and there were numerous fault segments, none of them
particularly large, that were near failure conditions.'"
Is that all?! If this esteemed gentleman cannot read a map of New Zealand
tectonic history then, politely, he should be bought an urgent ticket home.
Vibrant public discourse, however, is starting to extract more useful
references:
"Geologist Mark Quigley says the heightened activity isn't unusual after
the big shakes just before Christmas, and they're not likely to be over
yet. 'It's a virtual certainty of getting more earthquakes greater than
five, and even a moderate chance of another six going forward,' he says. Dr
Quigley says the location of these most recent aftershocks means there is
concern about a group of faults in Pegasus Bay, including faults offshore
of Kaiapoi. These haven't ruptured for thousands of years, but are big
enough to generate a quake of magnitude 7.0. 'Because of the way things are
shifting around out there, I think it's difficult for us,' says Dr Quigley.
'We don't know exactly when the last event was. It's difficult to put our
finger on that precisely and also the precise reoccurrence interval.'"
http://www.3news.co.nz/Fears-another-big-quake-could-be-in-store/tabid/423/articleID/238109/Default.aspx
Global warming is a good explanation for more tectonic movement and quakes
(as heated solids expand). We need to be seeing the big picture, which is
how much the lower South Island has moved west over the past five years
(during Fjordland quakes) and that the upper South Island has been forced
to catch up or let go (from Greendale eastwards). Only Banks Peninsula
stood in the way of the Greendale fault tearing straight out to sea. Which
is why the Port Hills fault took the strain and transferred it north-east,
under Christchurch and offshore.
Dr Quigs is finally speaking freely and stating the obvious, fairly for
the public (in sad desperation?), as "to be forewarned is to be forearmed"
- despite official obfuscation. With seismic stress moving from off New
Brighton and onto the more substantial Kaiapoi offshore fault, it is a
reasonable prediction to make that this too will go - sooner rather than
later, on recent ground performance.
An eventual magnitude 6.8 from this 'new' fault source may not be the
feared 7, but it will be no less remarkably scary.
We are wise to use best scientific advice from which to suggest
appropriate emergency preparedness - at all times. We lose nothing should
these steps prove unnecessary; we lose everything by keeping our head in
the sand (or our eyes on the tourist trade).
http://www.stuff.co.nz/the-press/news/christchurch-earthquake-2011/6208829/Mayor-defends-council-agency-performance
Kia ora, kia kaha koutou
~ Rik
ongoing earthquake trauma in Christchurch:
"Shocks may be last gasp of Feb 22 fault" says The Press -
http://www.stuff.co.nz/the-press/news/christchurch-earthquake-2011/6208949/Shocks-may-be-last-gasp-of-Feb-22-fault
- really?
Why has it taken SIXTEEN MONTHS for top earthquake specialists to start
looking in the right direction - East? Could this be revelatory of systemic
flaws in social privilege and academic hierarchy, producing intellectual
indifference? Quote 1:
"GNS Science natural hazards platform manager Kelvin Berryman said
yesterday that one theory was the Port Hills Fault, or splinters of it,
were responsible for the aftershocks hitting the city since December 23.
'I'm sort of comfortable in thinking this could be some residual activity
from the eastern end of the February 22 fault that didn't rupture all the
way out there,' Berryman said. 'We did see that there was a small patch of
that fault that does go offshore that may not have had much activity until
lately.' The 'patch' had been 'very productive' in generating aftershocks
since the two big quakes on December 23, he said. 'These 5.5s are pretty
substantial but only a quarter, or a third, of the energy of the 6.0 you
had,' he said. Berryman said GNS Science researchers would work this week
to come up with some answers on what was causing the swarm of quakes."
WHY was so much resource committed, so early, in the opposite and wrong
direction ?!? - see
http://www.chcheqjournal.com/2011/focus-network-hidden-faults/ of July
2010.
Quote 2:
"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.' Stress modelling for the
September 2010, February and June 13 quakes showed the area east of the
city had experienced a small increase in stress supporting quake behaviour,
Furlong said. 'The stress changes are relatively small. They in themselves
don't cause the earthquake,' he said. 'But if a region [silo thinking] is
suitably stressed prior to the stress change, then these small amounts of
stress change can advance or trigger the subsequent events. 'Basically, the
situation that Christchurch finds itself in is a region β and by this I
mean the entire region surrounding the city β that was suitably stressed
prior to the September event, and since that time we have seen a sequence
of events that pretty much follow the patterns of where stresses were
slightly increased by the September event. 'What has controlled the actual
space-time pattern of events is not totally clear, but in general it has
been pretty much an eastward march of earthquakes.' Some 'good news' was
that each of the big quakes appeared to be acting independently, he said.
'When the February event occurred, it did not reinvigorate the Greendale
Fault. Similarly, the June event did not reinvigorate either of the two
previous faults, and the recent suite of events has not really lit up any
of the previous regions, including the June rupture," he said. 'It seems to
indicate that each event is effective in reducing the stresses on its fault
such that they are no longer in a triggerable situation.' [? - 22-23 Dec
small Greendale quakes triggered the 6.0!] Some 'good news in all of this
is that the activity is moving east. 'After the June event, since it was on
a structure of different orientation β more north-south β it was unclear
whether the behaviour was changing. These events seem to indicate a return
to the slow but sure eastward march. [That overriding prognosis was already
obvious by October 2010 and should never have been derogated; it was
documented here: http://www.infohelp.co.nz/quake.html -
http://www.infohelp.co.nz/pix/200111-CQL-CHC-Screenshot-8x6.png ] 'None of
this really will make Cantabrians feel better about things, but what makes
this a bit intriguing is that it has continued in such a systematic way for
so long. I guess my arm-waving explanation is that the entire region was
sufficiently stressed, and there were numerous fault segments, none of them
particularly large, that were near failure conditions.'"
Is that all?! If this esteemed gentleman cannot read a map of New Zealand
tectonic history then, politely, he should be bought an urgent ticket home.
Vibrant public discourse, however, is starting to extract more useful
references:
"Geologist Mark Quigley says the heightened activity isn't unusual after
the big shakes just before Christmas, and they're not likely to be over
yet. 'It's a virtual certainty of getting more earthquakes greater than
five, and even a moderate chance of another six going forward,' he says. Dr
Quigley says the location of these most recent aftershocks means there is
concern about a group of faults in Pegasus Bay, including faults offshore
of Kaiapoi. These haven't ruptured for thousands of years, but are big
enough to generate a quake of magnitude 7.0. 'Because of the way things are
shifting around out there, I think it's difficult for us,' says Dr Quigley.
'We don't know exactly when the last event was. It's difficult to put our
finger on that precisely and also the precise reoccurrence interval.'"
http://www.3news.co.nz/Fears-another-big-quake-could-be-in-store/tabid/423/articleID/238109/Default.aspx
Global warming is a good explanation for more tectonic movement and quakes
(as heated solids expand). We need to be seeing the big picture, which is
how much the lower South Island has moved west over the past five years
(during Fjordland quakes) and that the upper South Island has been forced
to catch up or let go (from Greendale eastwards). Only Banks Peninsula
stood in the way of the Greendale fault tearing straight out to sea. Which
is why the Port Hills fault took the strain and transferred it north-east,
under Christchurch and offshore.
Dr Quigs is finally speaking freely and stating the obvious, fairly for
the public (in sad desperation?), as "to be forewarned is to be forearmed"
- despite official obfuscation. With seismic stress moving from off New
Brighton and onto the more substantial Kaiapoi offshore fault, it is a
reasonable prediction to make that this too will go - sooner rather than
later, on recent ground performance.
An eventual magnitude 6.8 from this 'new' fault source may not be the
feared 7, but it will be no less remarkably scary.
We are wise to use best scientific advice from which to suggest
appropriate emergency preparedness - at all times. We lose nothing should
these steps prove unnecessary; we lose everything by keeping our head in
the sand (or our eyes on the tourist trade).
http://www.stuff.co.nz/the-press/news/christchurch-earthquake-2011/6208829/Mayor-defends-council-agency-performance
Kia ora, kia kaha koutou
~ Rik
