7.0 earthquake hits Christchurch, New Zealand

reply to post by muzzy


There is scant info out there on the Springfield Fault which was only recently surveyed (c. 2005/6) - was here when they were up / down the fenceline using depth chargers to survey.

ir.canterbury.ac.nz...

www.cprm.gov.br...

That sure was a good one about a few minutes ago (22:15 NZT). Sure did roll for a while..... just waiting on geonet to update.
[atsimg]http://files.abovetopsecret.com/images/member/36baa12adf69.jpg[/atsimg]

Just had a large one, centred Waimari, a friend there said it was huge. Also Pegasus area has experienced two large ones in the five minutes. A month on, we're still going through large ones.

# Reference Number: 3382676
# NZDT: Mon, Oct 4 2010 10:21 pm
# Magnitude: 5.0
# Depth: 12 km
# Details: 30 km east of Darfield

Originally posted by Semoro
Just had a large one, centred Waimari, a friend there said it was huge. Also Pegasus area has experienced two large ones in the five minutes. A month on, we're still going through large ones.

It was a 5.0 and centered over at Templeton, not Waimari.

Was very noisy - rumble seemed to last for ages - then a huge jolt and more rumbles. A few mins later there was a 4.0.

And so it goes on.. just as many of us were getting back to some semblance of normality...

reply to post by MoorfNZ


Would you have described it as a "massive" aftershock?

Thats what the newsreader on NewsTalkZB said this morning on the radio news

USGS gave it quite a high reading 5.2mb, but 4.8ML (insert crosseyed smiley here)

Offically it was 5.014ML according to GNS (subject to revison)

Originally posted by muzzy
reply to post by MoorfNZ

 

Would you have described it as a "massive" aftershock?

No.. "bloody big", perhaps, but I'd reserve "massive" for a 6.0..

It's been feeling more active tonight. I wish the Oxford drum was visible as I swear my creaks and rumbles coincide with those small blips.. I'm 15km from Oxford/12km from Darfield.

"GNS Science natural hazards manager Kelvin Berryman said the pattern of aftershocks was changing. Instead of being located around the tips of the recently revealed Greendale Fault, which runs from near Hororata to north of Rolleston, they were more widespread. Earthquake scientists were "watching very carefully" for any signs the underground part of the fault might be rupturing towards Christchurch. "We would be very concerned about that," he said. "What the aftershock sequence does suggest at this stage is there's been a big area of rock being stressed at the ends of the fault that we didn't know about, and strain is being readjusted around the region." Asked if the Greendale Fault extended underneath the city, Berryman said: "We can't rule it out but there's no particular positive evidence at the moment."

I think that any one of us living in the area could have told them that the aftershocks were FAR more widespread than their "normal scenarios" showed.... I knew this sort of news was on the horizon, this was never going to be a normal event IMHO...

Source: www.stuff.co.nz...

From what I have observed, from the maps I created , the aftershocks are within a band width of 28km wide running West to East extending roughly 10km south of the Greendale Fault Trace and 18km north of it.
Thing to remember is the Trace is just that, the surface indications of the fault. It could be angled 10-12km down from the surface toward the north maybe. The main clusters are definitly more towards the city though.

Google Earth Version
Aftershocks to 28/9

Very quiet down here! Things are slowing down very fast and the mag's have dropped. Not quite back to "normal" activity though - not sure we ever will be.. things have changed in Canterbury, forever.

Yep not many being reported now.
But still dominating the NZ Lists

File Created: 5:15 p.m.. 12/10/2010 NZDT
Geographic Rectangular Grid Search
Latitude: -32.056 (north) to -48.868 (south)
Longitude: 164.065 (east) to -176.197 (west)
Source: Geonet National Earthquake Information Database
Date Range: 2010/10/11 to 2010/10/11 UTC
Magnitude Range: 0 - 9.0
Data Selection: Historical & Preliminary Data
Number of events : 13

Reference, Latitude, Longitude, UTC Date (yyyy/mm/dd), UTC Time (hh:mm:ss), Depth, Magnitude, Darfield Aftershock Felt
3386089, -43.57881, 172.05373, 2010/10/11 1:46:16, 5, 2.88, Darfield Aftershock
3386141, -43.57061, 171.95558, 2010/10/11 2:39:22, 5, 3.345, Darfield Aftershock
3386244, -43.6426, 172.45639, 2010/10/11 7:6:50, 5, 2.199, Darfield Aftershock
3386575, -43.60342, 172.619, 2010/10/11 7:9:10, 4, 2.093, Darfield Aftershock
3386247, -43.61073, 172.30521, 2010/10/11 7:14:35, 5, 2.321, Darfield Aftershock
3386256, -43.61448, 172.50832, 2010/10/11 7:34:43, 5, 2.729, Darfield Aftershock
3386260, -43.63634, 172.3756, 2010/10/11 7:48:16, 5, 2.557, Darfield Aftershock
3386325, -40.4236, 176.28607, 2010/10/11 10:46:46, 36, 3.817, Horoeka, Manawatu, Felt
3386623, -37.81549, 176.67757, 2010/10/11 12:46:11, 4, 2.356, o/s, NW of Matata, Bay of Plenty
3386411, -43.54025, 172.41081, 2010/10/11 15:0:56, 5, 3.337, Darfield Aftershock
3386438, -43.60498, 172.05745, 2010/10/11 16:29:46, 5, 3.529, Darfield Aftershock, Felt
3386522, -39.27816, 173.87761, 2010/10/11 20:42:42, 15, 3.186, SW of Newall, Taranaki
3386630, -40.79061, 174.77328, 2010/10/11 23:49:17, 16, 2.675, o/s NW of Kapiti Island, Cook Strait

Great talk given at Canterbury Uni by Dr Quigley on what happened and what's to be expected.

Large file

ftp.geol.canterbury.ac.nz...&%2027%20Sep/20100927.mov

Biggest aftershock for a while - widely felt... I was down the Waimakariri Gorge walking the dogs at the time and I heard it loud and clear!

4.1 - 20km West of Chch

Universal Time October 13 2010 at 0:28
NZ Daylight Time Wednesday, October 13 2010 at 1:28 pm
Latitude, Longitude 43.57°S, 172.43°E
Focal Depth 9 km
Richter magnitude 4.1
Region Canterbury
Location

* 20 km west of Christchurch

www.geonet.org.nz...

Busy day - just had a 5.0!! I was standing in the kitchen and it felt like a depth charge had been set off beneath the ground.. then all the crockery started rattling.. then I ran to the PC lol

Reference Number 3388384/G
Universal Time October 13 2010 at 3:42
NZ Daylight Time Wednesday, October 13 2010 at 4:42 pm
Latitude, Longitude 43.58°S, 172.43°E
Focal Depth 15 km
Richter magnitude 5.0
Region Canterbury
Location

* 20 km west of Christchurch
www.geonet.org.nz...

reply to post by MoorfNZ


Link doesn't work, could youenclose it in the "link" thingy so the address is complete.
I'd like to hear what he has to say.
Heard that 5.0 on the car radio on way home on Jim Moira's show, half an hour after it happened, thats a bit slack, a 5Mag not breaking news anymore?

Try this link, Muzzy

www.geol.canterbury.ac.nz...

It's the talk on the 27th/Quigley

Question for ChCh residents, has anyone else experienced the below...
I was at my parents place in Halswell today and twice we heard a loud noise (almost a bang but not quite), but very little movement (though an ever so slight shudder)
one was at around 6.30pm, the 2nd a little after 8.30pm saturday
The 8.30 event made all 5 people jump it was that loud. Only felt a slight degree of movement, the noise was far more than the physical feeling.
Geonet has not recorded anything for either time period

My parents have had this happen before a couple weeks ago also.
could it be a shallow but small mag quake ?

Has anyone else had anything like this happen ?

Thanks in advance and may the shaking stop soon......

reply to post by Brogue


This has happened frequently to both myself (out near Sheffield/Darfield), my parents (Kirwee) and my friends (Springston and Chch City).

GeoNet is only reporting larger quakes at the moment, and slowly catching up with the entry of smaller ones. We had a 2.8 almost right under us a few weeks back and no-one else felt it except for us and a few neighbours (we're rural so not many neighbours). My friend in Springston is deaf and she feels heaps AND is in the centre of all the aftershock activity over there nr Rolleston.

So, to answer your question - you may well have felt a close and shallow quake that has not yet been listed due to Geonet being so busy.

Note: the aftershocks are all so shallow, between 5km and 10km mostly, and we hear them out here very loudly as a boom - even 3's.

PS: If you look at Quake Live you'll see others have reported quakes about the time you mention but Geonet has reported on them yet. quake.crowe.co.nz...

reply to post by MoorfNZ




Cheers I wondered if it was something like that.
very unnerving it is.
It will be nice when things settle down

reply to post by Brogue


Yes, it will be nice when things settle down. Unfortunately it may take some time as the displacement takes some time to 're-equilibrate'.

I've been noticing the rumbling (almost sub-audio, intensely deep,and constant) is back after a hiatus which I'm sure was real rather than imagined and my wife has said that she has started feeling sea sick again.

Dr Quigs is hard to track down at the moment, with it being the last week of lectures and all, but he is giving a public lecture on Wednesday evening which I would thoroughly recommend if you are interested ion the mechanisms of the fault as well as the aftershocks.

I don't really appreciate the fact that I am becoming used to these shakes.