GeoNet - Shaken not stirred

You asked for a faster GeoNet......

2012-03-02T08:59:00.001+13:00

Well next week, you get it!

On Tuesday 6th of March our Beta website "GeoNet Rapid" goes live. The team here at GeoNet have been working on this new system for the past year and are excited to see what you think!

The basics:
- Speed : You will be seeing details of earthquakes from around 2 minutes of their occurrence, as a computer system locates the earthquake as soon as the data arrives (rather than a person waiting for all of the data).
- Numbers : More events will be posted to the rapid site, not just the larger/more widely felt events that we put on the 'recent quakes page' (we located over 19,000 earthquakes last year, so there are plenty!)
- Regions : Its easier to view earthquakes in your area, with options to see various regions in NZ as well as 'all' or 'felt' events. You can also view statistics on the earthquakes in the various regions in the last week/month and year.
- History : As more data comes in, the details of an earthquake can change (magnitude/depth etc.) You can see all of these changes right up to the final location as all of the data has been received from our instruments out in the field. The first location can be made in under a minute, as the first data comes in!
- Issues: This is a beta testing site, so things can go wrong! Don't panic, thats why we have the test site, to discover all issues and fix them!

- Remember: geonet.org.nz is still the official source of EQ information, and our duty officers will still be locating the quakes here.

Screenshot of the 'regions' page

Links to the site will be available on the GeoNet website on Tuesday (and on facebook / twitter etc) as well as a comprehensive news story with information from the history of the new system, to what exactly it does!

I will be giving more blog updates on how to use the website and as more features are added, and for those more g33k types out there - you may like to check out the GeoNet Development blog here.

A great example of how fast the new system will be, is shown in the diagram below comparing automatic location times and manual 'human' times to events located on the 23rd of December.

On 23 December 2011 (UTC) there were 106 earthquakes over magnitude 3 in the Canterbury region. On average SeisComP3 (SC3) had a first automatic location two minutes after the earthquake occurred and a final automatic location after four minutes. Compare this to the fifteen to twenty minutes it typically takes to make a manual location

In January i gave a sneak peak at the GeoNet App that we have been working on, here. We plan to have this available on the Android marketplace the following week! < and iPhone later on in the year>

Drums - not the musical kind!

2012-01-30T15:45:00.001+13:00

Now i did a blog last year on how to read the earthquake drums on our website (you can read it here) but we have had quite a few queries recently about the scale and things showing up on various drums - so i thought I'd have another look!

Some key points:
- The drums have scales (top right)
- The scales automatically change depending on the current activity (we don't change them to 'hide activity', if they didn't change you wouldn't be able to see anything!
- The drums often show noise -wind, stock, traffic etc. as the instruments are very sensitive (although we do try and put them in quiet areas).
- If you see an event on the drum and its not on the 'recent quakes' page, it probably wasn't felt.
- There are several different kinds of seismometer in use, so you cannot directly compare them.

And we don't use these drum images to locate the earthquakes, they are just there for you to look at!

The drums on the left, are in the 'Canterbury Quakes' tab here, they will have different scales and you can't directly compare quakes.

Under our earthquake tab you can find Quake Drums, these show instruments from all over NZ. The picture on the right is from December 23 2011, as you can see it clearly shows how widely events were picked up across the country.

Edgecumbe 1987 event on Hicks Bay drum

Here is an example of what the earthquakes looked like on the old drums. This picture (left) is off a drum in Hicks Bay and shows the March 1987 Edgecumbe earthquake and aftershocks, as you can see - its a mess!

Earthquakes - A competitive sport?

2012-01-20T16:04:00.000+13:00

New Zealanders are well know for their competitive nature when it comes to sport, which is great as we are pretty good at it! But it has come of a bit of a surprise lately at the 'mine was bigger than yours' mentality people seem to be getting regarding earthquakes.

I'm sure most people remember the small earthquake in Auckland last year, yes everyone had a bit of a laugh and there were plenty of 'oh no my latte has fallen over' jokes! But in all seriousness Auckland does not get a large amount of felt earthquakes, and living on top of over 50 volcanoes we should let them worry a bit when they do feel shaking - as this is often a precursor to eruptive activity!

Fence crossing the Hope Fault - it was straight until 1888!

Back to the rest of NZ - at GeoNet we record over 15000 earthquakes every year - luckily most are not felt! We do however, get a few 'biggies' every now and then, here is a wee jaunt through our earthquake history::

North Canterbury 1888 ~ 7.1
This earthquake had a shaking intensity of MM9, it occurred on September 1st 1888. As you can see in the picture on the right - it created a fair amount of land movement, there were also numerous landslides, liquefaction and broken chimneys.

Wairarapa 1855 ~ 8.2
With a maximum intensity of MM10 this earthquake was felt all over NZ, around 7-9 people were killed and 5 injured. This is also the famous event that uplifted many areas in Wellington including: the Basin Reserve (sports ground) which used to be under water, as well as the harbor ( Lampton quay used to be the waterline), and even the land our airport is on.


Fault Scarp in Buller Gorge.

Buller/Murchison 1929 ~ 7.8
On June 17 this large event occurred, luckily in an area sparsely populated, though it still killed 15 people and injured 1. The quake had an max intensity of MM10 and was felt all over NZ, and damaged many roads, bridges and buildings. The quake also created 38 new lakes after slips blocked rivers (21 still exist today). If you look at the picture on the left, the wee man on the bike is on the other side of the road, now 4m higher than the rest!

Severely damaged road - Hawkes Bay

Hawke's Bay 1931 ~ 7.8
This earthquake caused the largest loss of life and most damage of any quake in NZ history (prior to the Canterbury events) The MM10 event killed 256 people and injured thousands, the earthquake was followed by devastating fires that were unable to be stopped as the water mains were broken. This event also changed the coastline and deformed much land in the area.

Rift in a paddock - Edgecumbe.

Edgecumbe 1987 ~ 6.5
This event is well remembered in NZ history, it occurred on March 2nd and had a max shaking intensity of MM9. 25 people were injured, and although many buildings collapsed - fortunately they had been evacuated following a large foreshock.

Dusky Sound 2009 ~ 7.8
This event is the largest in New Zealand since Marlborough 1848 and Buller 1929. With a max. of MM7 it triggered numerous landslides and even a small tsunami.

And of course we have the 2011 Christchurch ~6.3 earthquake, with MM9, 181 people killed and 164 seriously injured. For more info on the canterbury events, see our pages here

Although the size of these earthquakes vary, it is interesting to see how the maximum shaking intensity(MMI) is pretty similar. Looking at the maximum shaking intensity is a much better indicator of how earthquakes effect people and the environment, rather than just the magnitude. You can read more on the MMI scale here

Now this is just a few of the major historic earthquakes in NZ, for more info on these events and others go to our 'historic quakes' page here

And back to my original point(s)
*All of New Zealand gets earthquakes, both small and damaging. So stick together - offer help and words of support, rather than tell people to 'get over it' as it was 'only a baby one'. We are only a small country, stick together!
* and remember to look at the MM shaking intensity of an earthquake before you judge on its size, it may have been small but strongly/widely felt!

2012 - A taste of things to come!

2012-01-10T14:36:00.000+13:00

As most of you know, we announced a while back that we were working on some exciting new things for the website, these will be out for user testing in a few months, in the meantime here is a sneak peak...

Introducing the GeoNet smart-phone App...

It has some really cool features and our team of geeks are adding new things all the time! As you can see on the pic to the right ->
it is showing earthquakes from as little as '9 minutes ago' - so yes that means you can find out (roughly) how big etc an earthquake was within a few minutes. It generally takes between 2-5minutes for a preliminary result and as more data becomes available the figures can change slightly (its similar to the system USGS use at the moment).

This pic on the left <-- shows some older events, but also the color coding, the higher the intensity the darker shade of red the event will be. So white = small, light red = felt, deep red = the big ones!

You can also click on each event for more info (links to the www), map, refresh the event and share it.

There is a map button so you can see all of the recently located events and click on each for more info, and you see have 'all' events or select 'my' which allows you to choose events of a certain intensity, from a certain place and even (using your GPS or wireless) quakes near your current location.

So i hope you all enjoy this sneak peak, by the time it is released it will probably have even more neat functions!

NB: at the moment it will just be Android, but we do want / and will be working on an 'i' friendly App.

Happy Holidays ~ the last blog for 2011!

2011-12-21T14:53:00.001+13:00

Hard to believe its nearly the end of the year already, and what a year its been! From the hard times following the devastating quakes in Canterbury, to the highs of GeoNet turning 10. We are all hoping that 2012 will come with less geological hazard activity, well a little bit is OK - we are on a plate boundary after all!
I hope to blog more adventures with our technicians, and other exciting things that happen at GeoNet including the replacement of our earthquake location system (more info here )

The GeoNet tree - with quake proofing!

As many people begin the wind-down at work, i thought i would remind everyone that GeoNet is 24/7, when you feel any earthquakes over the break, don't worry our team will be onto it! Each day (including Christmas) we have one seismologist - based at Avalon, and one volcanologist - based at Wairakei on duty, armed with pagers and close to their computers. So fingers crossed for a uneventful (hazard speaking) few weeks, with some nice weather for BBQs and fun at the beach!

Speaking of weather, my friend Philip Duncan runs the WeatherWatch website, and they have the official Christmas Day forecast here, and its looking good - don't forget your sunblock!

So happy holidays and thanks to all the GeoNet fans out there from myself and the team at GeoNet, we look forward to bringing you new and exciting things in 2012!

- And i hope everyone remembered to quake proof their Christmas trees!

SARA

Nelson Rapid Response

2011-12-20T11:45:00.000+13:00

With a state of emergency still in place in Nelson following last weeks heavy rain/flooding and landslides GeoNet are currently working with Civil Defence, with our landslide rapid response capability.

Sam working hard

Technicians are in Nelson today installing a continuous-GPS site at Grenville Terrace, on a major landslide where 30 houses have already been evacuated as further land movement is possible. cGPS sites, using satellites, allow scientists to accurately record ground movement

Info on GeoNets landslide rapid response capability here

Our thoughts are with all of the displaced families and those affected by the flooding/landslides especially so close to Christmas!

cGPS - freshly installed

Drill rig

Foo Fighters rocked Auckland!

2011-12-15T11:25:00.002+13:00


You can almost pickout individual songs on the signal!

Two seismic stations in the Auckland GeoNet seismic network recorded the ground literally rocking to the Foo Fighters gig at Western Springs on Tuesday night. The Herne Bay -HBAZ and Eden Park -EPAZ (with IESE-Auckland Uni) stations are 1.5 and 2km from Western Springs respectively and recorded a strong low frequency signal associated with the Foo Fighters gig.

The first vibrations were recorded around 7:30pm, part way through the Tenacious D set, but the biggest shakes started at 8:20pm when the Foo Fighters took the stage, and then it all went quiet at 11pm when the gig ended.
The concert vibrations were recorded as a semi continuous harmonic signal with a peak osculation of 3Hz, ie the ground was shaking 3 times per second in a nice rhythmic motion. There are lulls in the signal between the songs and peaks in signal intensity during the songs.

The cause of the shaking is most likely the weight of the 50,000 fans dancing, as 50,000 fans is equal to around 5,000 tonnes of mass moving(or moshing)on the ground for the duration of the concert. This set up a nice harmonic vibration in the ground which was recorded in our nearby borehole seismometers.

The sound system, probably contributed as well, especially the bass frequencies coupling in to the earth. The signal is similar to volcanic tremor that is recorded at places like Mt Ruapehu and White Island, however the strong correlation in time with the Foo Fighters concert and the fact it was only recorded on the 2 stations close to Western Springs assured us it was of man-made origin.

Detail of the signal showing the 3Hz vibration

This is not the first time the Auckland instruments have picked up neat sounds, the Rugby World Cup finals were also seen!

Thanks to Craig Miller and the Wairakei GeoNet crew for the info!

Out and about - Auckland

2011-11-23T15:06:00.001+13:00

I recently traveled up to Auckland to speak at the annual 'Planning for a volcanic crisis' short course - this is a two day course designed for people involved in all aspects of natural hazard management, emergency managers, local council and planners etc. Auckland is a great place to hold this course as it is built upon a volcanic field made up of over 50 separate volcanoes!

Volcanoes in NZ

There are three types of volcanoes in New Zealand:
*Cone eg. Ruapehu and Egmont,
*Caldera eg. Taupo,
*Volcanic field eg. Auckland and Northland,

You can find more info on the different types of volcanoes here .

In Auckland each eruption has occurred at a different location, with a single 'hot spot' of magma about 100km below the city, this means that any new activity will come from a different area - not one of the existing volcanoes. Today most of these volcanoes have been quarried, made into parks or been built on.

The field will probably erupt again as overseas examples show that volcanic fields can last for a very long time (over 1million years) and the Auckland field is only around 250,000yrs old - if it helps volcanic fields typically produce small
infrequent eruptions compared to the other types. You can get more information, and see how GeoNet monitors the Auckland Volcanic field here

Islington Bay

The last eruption in Auckland was about 600yrs ago at Rangitoto Island, we headed over on a ferry to check it out! We had great weather for the trip as well!

Rangitoto Island was formed during two eruptions, 600 and 550years ago, it is 260m high and can be seen just North-East of Auckland city. Thanks to DoC Rangitoto is pest free and also the home to the worlds largest Pohutukawa forest!

You can see various neat geological features on the island, and even explore lava tunnels. These are formed from paehoehoe lava flows, where the exterior cooled and crusted over creating a tube that allowed the molten lava within to continue flowing, as the lava flow decreased at the end of the eruption, these tunnels were left behind. (if you visit take a torch, sturdy shoes and don't think of wetas!!)

A video of some of the sights below...

Are you prepared? Get Ready, Get Thru

Out and about - Christchurch Day 2

2011-11-02T16:27:00.000+13:00

Hi-viz swarm at Brighton

All of the forum attendees donned their hi-viz vests, and a sea of orange and yellow went out to visit sites of interest to see the physical impacts of the earthquake and the progress with recovery.

One of the sites included the (now old) Brighton sub-station which sunk quite a bit due to the liquefaction -you can see in the photos below - a new substation has now been built.

Note the door!

On a slight lean!

Another interesting site we visited was the Bromley Wastewater
treatment plant (just a tad stinky!) Their main problem to face was the large amount of silt coming into the plant, with not much physical damage caused by the actual ground movement.

The various treatment tanks

This was slightly unnerving!

Luckily they had these!

Out and about - Christchurch

2011-11-01T21:02:00.000+13:00

Today i am in Christchurch for the annual 'National Lifelines Forum', this is where members from our energy, telecommunications, transportation and water sectors gather and discuss experiences/lessons etc from the past year. Obviously this year there are a lot of discussions on the Canterbury earthquakes and how each sector was damaged and dealt with the various challenges this presented. GeoNet (including myself) will also be presenting tomorrow.

Going for a walk in the sun at lunchtime, it was strange to see the beautiful buildings in various pieces, and the skyline full of large cranes, but nice to see the businesses still open - even if they had to move to quirky temporary sites.

One place that i was please to see open was the Canterbury museum, where I popped in to visit a friend, he kindly took me around and showed what little damage the museum sustained, thanks to extensive earthquake-proofing some years ago, i also got a sneak peek at an upcoming exhibit - Hearts for Christchurch "which showcases an amazing array of more than 4,000 stitch-craft hearts from around the world. The project of an inspirational Napier woman, Evie Harris, who started creating and gathering the hearts after the February earthquake."

I then went to see the new 'container mall' at Cashel street, it is amazing and it was great to see so many people out enjoying the sun and shopping.
Pics below . . .

Cute Kia Kaha 'flower'

Arts Centre

Cashel St 'Container Mall'


Bridge of Remembrance

Volcano cameras ~ Bugs, aliens and more!

2011-10-26T13:24:00.001+13:00

This picture was sent in on the weekend (great spotting, thanks Ross) its a great pic as you can see a black-backed gull flying past (and you can actually see the top of ) Mt Egmont /Taranaki!

It got me thinking to some other strange things we have seen on the volcano cameras over the years ....

On the left, a spider has a made a home on the Ruapehu cam, and on the right a fly is hanging out with Dino on White Island.

You can also see Dino supporting the All Blacks here

We often get emails in from people curious about black dots (or aliens) showing up on the webcams:

I can assure you these are not aliens! When the sun is shining directly onto our cameras, they find it a bit bright so the sun is shown as a black dot!

At white Island you can also see the robot-looking camera reflected onto the image.

And here a red 'alien' caused by another camera reflection.

We often see the helicopters landing on White Island and various tour groups (so next time make sure and wave)

To see the current pictures from the volcano cams click here they are updated every 15 minutes. You can also view an animation of the last 48hrs of still pictures for each camera, eg White Island here

You can also see our volcano resources page here where you can access older images (going back to 2000), and see various publications as well as other data publicly available.

Out in the field - Taranaki 1.1

2011-10-21T18:24:00.000+13:00

The second part of our day was spent out in the field, the TRC have rain gauges at a few of our sites so they travel out there often and have a look at our sites to same sure they are looking ok and help keep our sites tidy (clearing overgrowth, fixing fences and aerials etc)

First stop was the North Egmont visitors centre to our seismograph site NEZ which was all in order (despite the rain and hail) and after checking the councils rain gauge (very full) we went to our next site.

DREZ

DREZ is located on a dairy farm, and once we waited for the cows to meander their way to the milking shed, we found the site. With no cows to eat the grass within the fence, it tends to get quite long and can even block the solar panels, so Andrew took to it with a weed-eater and its all pretty again!

We keep detailed information on all of our sites, including landowner details and precise details on how to get to each site. Since its construction in 2008, the farmer has moved some fence-lines and the site is in a new paddock, so i made notes of the new directions to the site, and this will be updated on our DELTA database - where this information is kept.

DREZ after clearing the grass

German Hill

We then did the same at our German hill cGPS site.

Out in the field ~ Taranaki 1.0

2011-10-19T11:31:00.001+13:00

This week i traveled up to New Plymouth (to some not-so-fantastic weather) for a meeting, and also i met up with Andrew a Hydrology Officer from the Taranaki Regional Council (TRC). Back in the pre-GeoNet days the council looked after a small network of instruments around the area, we have since taken these over, upgraded them and added a few more sites (you can see the network here). Due to their experience and knowledge of the network, the council have a unique relationship with GeoNet where their staff help maintain our current sites and occasionally help our technicians build new sites - this saves a long travel time as our technicians are based in Taupo and Lower Hutt!

Our first stop was the Taranaki Emergency Management Office (TEMO) which is home to one of our volcano cameras (which you can see on our website here), strong-motion instrument NPCS and a repeater-hub where data from other sites goes to TEMO and is then sent on to our data centres (at Wairakei and Lower Hutt).

TEMO

Volcano camera (circled) New Plymouth city in the background

The strong-motion instrument.

Data from other sites coming into the 'repeater hub'

Volcanoes, a Dinosaur and Rugby?

2011-10-01T21:25:00.000+13:00

So its a big weekend rugby wise all around New Zealand - go teams!

As you know GeoNet monitors all of New Zealand's active volcanoes - one of which is home to 'Dino the dinosaur' - normally he just chills out in the crater of White Island, but he has recently decided to show his support to the boys in black!

So we hope everyone has a fantastic weekend, and you can see Dino here (during the day!!)

Out in the field - the perils of lightning!

2011-09-27T14:01:00.000+13:00

Last week one of our Senior Technicians - Dan, went down to Wednesday Peak and Welcome Bay in Fiordland (here) to replace and upgrade some radio gear that had recently been damaged by lightning. These sites have the important task of transmitting data from the tsunami monitoring site PUYT (Puysegur) back to HQ.

Wednesday Peak

Helicopter leaving the site

Dan then traveled to the other end of NZ, to North Cape (here) (along with a technician from Maritime NZ), to investigate an outage of the tsunami monitoring site NCPT (North Cape). When they arrived it was clear that the lighthouse next to the site had sustained a direct lightning strike and was effectively destroyed, the lightning had also destroyed all of the equipment for our tsunami gauge. Although lightning protection was installed, it was ineffective against such a large strike. Everything at the site was replaced, with divers traveling within the next week to replace the actual tsunami sensors in the water - as the lightening traveled all the way down (over 250m) to the sensors in the water!.

North Cape


Lighthouse and GNS Site(right)

Lightning damage inside the cabinet

Although traveling to these remote locations involves long hours and hard work, the technicians do get to see some amazing views of our beautiful country, and occasionally some wildlife...

This whale was spotted in Te Waewae Bay.

Thanks to Daniel for taking the pics and telling me what he got up to (and for putting up with my pestering)

Exploring the website - ShakeNZ

2011-09-19T20:56:00.000+12:00

When you go to the GeoNet homepage you will see a map of NZ covered in small squares, this is 'ShakeNZ'. Each one of the squares gets near real-time shaking (this means in a few minutes, not right away) from our instruments out in the field. So within a few minutes of an earthquake, you can look at the map and get a rough idea of where it was and the intensity of the shaking.

The key thing here is actually to do with the key! The pic on the right is the key for the map, which shows intensity, not magnitude! So when there is an earthquake and you can see an area of coloured squares, they are showing the intensity of shaking not the size.

The numbers correspond to the Modified Mercalli Intensity Scale, this is a really handy way to describe the effects of an earthquake, and is generally better than using the magnitude alone (as a mag 4 quake at 5km depth will produce a higher shaking intensity than a mag 4 at 10km depth) It goes from MM 1 (barely felt by a few people) to MM 12 (complete devastation).

<--- This is what the map looks like with no activity, small blue/purple squares (blank = no data)

This is the map after a mag 5.5 earthquake, 30km deep near Wellington. -->

Now occasionally when we have technical issues ( the instrument is having a bad day, or a tech is out fixing something) there will be a 'rogue' square! Its usually pretty easy to see that its an error and not a large earthquake as there is just one square showing a high intensity, and when there is an actual event multiple squares will be 'lit up' .
The map on the left shows one station/square showing an orange square, or 7 intensity of shaking, if this was an actual event the squares close by would also show some level of intensity. There are more examples here.

You can also use an interactive version here and go from 60min to the present - a cool way at looking at the squares light up following an earthquake.

Felt Reports: Then & Now

2011-09-02T11:56:00.000+12:00

GeoNet collects earthquake data directly from the public via our website where people can answer questions about what they felt during an earthquake. We use this feedback to assist with mapping the distribution of shaking intensity of earthquakes(see here ) and with scenario planning for future earthquakes.

These days its a quick questionarre on our website, however, back in the early 1900s (pre-internet -shock horror) things were slightly different! There was no GeoNet and no network of instruments across New Zealand.

For many years dedicated volunteers completed reports, filling in paper questionnaires and sending them to the observatory in Wellington. Pre-1930s these, along with newspaper clippings, were used by scientists to calculate where an earthquake was located. This was difficult in NZ as most people lived by the coast, so not much was known about the effects of earthquakes further inland.

Christchurch 1921

We keep all of these old records here at GeoNet
and they can be quite amusing to read, i have scanned 3 examples of 'felt reports' and one old Press article for you to look at here -->

Christchurch 1921

So next time you feel an earthquake and are (very paitently of course) awaiting the details from GeoNet, think back to the earlier years - they never got to find out how big the earthquakes were!

Palmerston North 1923

Out in the field - Canterbury : Day 3

2011-08-28T18:53:00.000+12:00

Day 3 - Lara and i packed up and headed back up to the hills above Akaroa, where we put out one more test site.

And then drove back to Christchurch

With a quick photo-stop at McQueens Valley, home to our popular MQZ.

The last stop was up Richmond Hill at Sumner, it was the first time i had been there since the Sept 4th quake, and wow what a difference. The roads were definitely 'munted' (a popular post-quake phrase) and it was surreal driving around the coast and seeing the wall of containers, to protect from the rockfalls, and the houses perched precariously on the edge of the cliff.

There were still Port-a-loos on every street, and very damaged houses, on the drive up the hill.

Our temporary site is right at the top, on a new subdivision , we changed over the batteries and then it was back to Wellington. The site has amazing views, i wonder if people will still buy there?

From up high, things almost looked 'normal'.

Nb: i didn't make Lara do all of the hard work, i did manage to make it into one photo ; )

Out in the field - Canterbury : Day 2

2011-08-26T13:14:00.000+12:00

Another beautiful day, our first two stops were temporary sites, where we changed over the batteries and retrieved the data cards.

Both sites are on farm land and we are always grateful to the owners for allowing us access to their property, and to leave our instruments there for months at a time.some farmers are fantastic and even give us a hand, the pics right and below show the fantastic views from one such farm, where the kind owner helped us get our heavy batteries up and down the hill on his quad-bike.

We then went out searching for ideal test sites for permanent seismic stations. After the scientists have located ideal areas on maps, we then have to go out to the areas to see exactly how 'ideal' they are! As we need to find areas with low noise (cars, wind etc.) good base rock and relatively easy access for the techs to build them. Once we find suitable areas we then have to track down the landowners and ask for their permission. Luckily this was relatively easy today and they were fantastic, and happy for us to 'play' on their land.

Step 1 - Dig a hole for the vault

Step 2 - Concrete a paving slab to the rock below "to essentially bond the sensor to the rock" to make sure you are recording the actual earths movement, as opposed to the movement of the loose earth around it.

Step 3 - Put the seismometer into the 'vault' - it has to be perfectly level and point north to allow us to derive direction to the seismic waves/earth movement. A lid is then placed on top and the earth filled back into the hole.

Step 4 - Connect the seismometer to the Taurus (data logger) and battery (power), and package up all nicely into a tarp to protect from the weather.

Voila!

Out in the field - Canterbury

2011-08-23T22:22:00.000+12:00

Today i flew down to Christchurch with one of our Operations Scientists at GeoNet (and acting Network Development Manager) Lara. Our task is to replace batteries from our temporary seismic sites around Christchurch, take down some test sites, and scope around for new test areas for permanent sites.

It was a beautiful sunny day, with the odd patch of snow around, left over from last weeks storm! After getting our hire 4WD, we met up with a ChCh based GNS technician who loaded us up with batteries, we then went to our storage lockup and grabbed some more gear (shovels, concrete etc.) and we were off to our first site.

Loading up!


The Christchurch GeoNet temp. storage unit.

Berry Farm

The first site we visited was not far from the airport, and in a farm, so easy access. It is a temporary seismic instrument put out following the Canterbury earthquakes. Technicians have to come out every few months to change the data cards, and replace the batteries.

Summit road - lots of snow left

We then drove to Akaroa via Summit Road, and to the test sites. These are sites carefully chosen by scientists (with maps) to increase our coverage of the Canterbury region (along with NZ as a whole). Technicians then go out in the field (I'll go into this more tomorrow) and install the test sites for a few months, and these are then recovered and the data studied to see how the readings are (eg if its too noisy)
All that is left is a rebar pole and a few rocks painted bright
pink for the boys (so they can find the correct area) to go out and install the 'proper' site later on!

Dismantling the first site

I think the boys should be able to find this!

The sun was setting, and the cows were coming in for a look.

The recent snow, and its melting had made the paddocks pretty muddy so we had to lug all of the equipment back to the ute via foot, the batteries weigh 24kg - so this was a good work up for dinner! The last site we went to, the road was actually blocked by about a foot of snow, so we had to scale fences as well (i'm a shocker at this!) as carry the gear accross the farms.

The last site, racing against the setting sun.

Beautiful view

We finally got to Akaroa at 7, after a quick dinner and shuffle of the batteries in the ute, its off to bed all ready for another big day back out in the beautiful Akaroa hills.

GeoNet - A Quick Tour

2011-07-29T13:35:00.000+12:00

Ever wondered what it looks like here at GeoNet, well wonder no more ....

Exploring the website - Landslides.

2011-07-28T09:37:00.000+12:00

Landslides are a common hazard in NZ, GeoNet has a rapid response capability (a team of experts ready to go to a large/damaging landslide) and is compiling a database of New Zealand's landslides.

We also monitor some large slow moving landslides in New Zealand, we have information on these landslides (http://www.geonet.org.nz/landslide/) as well as interactive graphs which you can use to see the various GPS, borehole and rain-gauge sites.

To the right is a graph of the Utiku landslide, showing a period of high rainfall in Sept (C) leading to an increase in groundwater level (B) and subsequent ground displacement (A)

You can also read reports from our rapid response team here.

Exploring the Website - ChCh Aftershock Forecasts

2011-05-31T15:56:00.000+12:00

As its been in the news a bit today i thought we could look at the aftershock forecast map for Canterbury.

In the Canterbury Quakes section of our website (here) there is a tab called aftershocks.

Aftershock Forecast Map

Here you will be able to see an aftershock forecast map. This map is updated hourly, covers a 24-hour period and shows the probability of experiencing slight damage or MM6 shaking. (MMI Scale)

Probabilities are calculated using a background of geological and earthquake information and all of the earthquakes that GeoNet records are looked at. For each event the probability that it will be followed by an earthquake large enough to cause strong shaking is calculated from the known behavior of aftershocks. The shaking that would be produced by such an earthquake is then predicted from the known relations between earthquake size and shaking patterns. The likelihood of that shaking is then added to the background probability on the map.

More detailed info here

Below the map are a few tables:

The top show the number of afershocks that have occured (vs how many were expected) and then there is a
table that shows a one month forecast of expected aftershocks of magnitude 4.0-4.9, and 5.0 +.

Dr Matt Gerstenberger produces these aftershock probabilities for one month ahead and they cover the entire aftershock zone, which extends from Sheffield in the west to Rangiora in the north to Lincoln in the south, and right across Banks Peninsula.

Forecast Table

NB: We are currently looking into extending these forecasts (covering a few months, rather than just one) on our website, shortly.
These longer range forecasts are where the figures in todays news came from. And as far as today's news, the figures for Christchurch metropolitan area are roughly one quarter of the figures given to CERA. So 23% probability for Canterbury becomes 6% probability for Christchurch.

In rough terms, it means the quake probability for Christchurch has become similar to many other parts of NZ such as Wellington, Hawke's Bay, Wanganui, and Poverty Bay where quakes are more frequent. The initial driver of this increased activity was the September M7.1 quake. It started an aftershock sequence that will continue for many months, these aftershocks will gradually get less frequent, but there is still a small chance of a larger aftershock for a while yet.

And.... Its not saying there will be another large event, its saying what the probabilities of one occurring are - there is a difference, and they may not happen. All you can do is be prepared, it is the earth we are talking about here!

Friday - The end of the world is nigh...

2011-05-20T11:07:00.000+12:00

This year has really been the year of 'predictions'! End of the world, large earthquakes, large tsunami etc. have all come at us. (we won't even go into the Moon!) The most recent is the May 21st where .. well its confusing but something to do with rapture and doomsday and then the 'end of days'. But don't forget we also have the big world end on December 2012 (tis very confusing keeping up with them all)!

So in light of this i thought the above song would fit in great for this weekend - REM 'The end of the world'.

PS - No one can predict earthquakes, tsunami, nor the end of the world!! So have a great weekend!

Network - Exploring our website data - Part three

2011-05-07T15:51:00.000+12:00

Ever wondered where all of our instruments are located around NZ? Its all on our website here!


ROPS - Strong-Motion site at Rotorua Police Station

* DELTA - is our database that has detailed information about each of our sites (tsunami, seismic and strong-motion) Including maps, coordinates and photos of the instruments.

You can search by name, location or use the map.

* Network Maps - There are two options here, the first page is an interactive map that allows you to choose what you want to see (different networks, operational, under construction etc.) and zoom around on the map on NZ.

The second option is to view the static network maps (the tab is up on the left). Here you can see full maps of NZ showing our seismograph, cGPS, strong-motion and tsunami sites. Underneath is a map of NZ where you can click on regions and see a more detailed view in each area. All of these maps are automatically updated daily.

ScreenShot of the interactive map.

Auckland Region Network Map

Ruatahuna National Network Site Build - The video!

2011-04-15T09:17:00.000+12:00

Music: Dragon - Rain

Diary of a new site build - day 4

2011-04-14T09:40:00.000+12:00

Fitting the solar panels and building the fence

Finally the sun came out!

The finished site

Day four was an interesting one, by the time we drove out to Ruatahuna it was raining really hard! And as much as we wanted to turn around and drive back to our warm hotel rooms, we all put our wet-weather gear on and drove (Rhino) up to the site. Lara and i got to work digging the post holes for the fence, while the boys started fixing the solar panels to the framing, and putting the satellite dish up. The cabinet was then put in place, this houses all of the wiring, batteries and a strong-motion instrument (called a Basalt - apparently its from the 'rock series' of equipment!) . And we could then finish the fence, its job to keep out the nosy cattle - sheep are ok as they keep the grass down!

The rain finally eased up and the wind decided to add to the fun! So running after stray equipment and cement bags as well as trying to keep the tarpaulins over our gear was amusing.

Unfortunately due to the bad weather all week it wasn't possible to completely finish the site, so a couple of technicians are heading back out next week to wire up the solar panels and the vault to the cabinet. And install the strong and weak-motion instruments, that will do all of the earthquake recording!

A more detailed story on the site build will be in the next issue of the GeoNet News, including the science involved and how the site was chosen.

The finished vault

View to the site from the 4WD track

Pretty solar panels all ready to soak up the sun

FINISHED! We did think about GNS but decided YMCA was easier!

Diary of a new site build - Days 2/3

2011-04-06T21:18:00.000+12:00

Shopping list for the trip:

3 tonnes of concrete mix
Timber (8 6m 4x2, 10 1.8m 4x4, 38m 4x1)
Metal Cabinet (1.5m x 1.5m x 0.65m)
6 125W Solar Panels
Solar Panel Frame (lots of steel piping!)
50m of Alkathine Piping
1 x concrete mixer
1 x generator
Tools - LOTS!
3 x 4WD vehicles
2 x trailers
1 x Rhino (See Photo 1)
1 x Helicopter
4 x GeoNetters

Ruatahuna is a two hour drive from Rotorua with most of the drive a winding unsealed road through the forest. Day 2 started with rain, lots of it! The site was at the top of a hill on farmland and was a 15min Rhino ride on a 4WD track up and around the hills. Due to the weather,a helicopter and concrete was out of the equation so it took quite a few trips to get the gear up to the site, then we could start the digging! Daniel was hard at work on the vault while Lara and i started on the 15m trench, and Sam was in charge of bringing up the gear in the Rhino. By the end of the day we were all very wet and tired, although the rain did give us a break for lunch! (What a way to spend my birthday!)

The Rhino!

The base at the bottom of the hill

Daniel digging the vault in the rain

Is that heading our way?

Trench - girls can dig great!

All that digging is hard work!

The site

Day 3 was fine! Cold, windy but the sun did peek out at times. The helicopter was called and took the heavy gear - concrete, timber, cabinet and solar panels (and i snuck on!) up to the site. We then got the vault and base for the equipment cabinet, ready and mixed up the concrete - lots of it! Once the concreting was all done we started assembling the frame for the solar panels, then packed up just before the darkness set in.

Dropping off some gear

Daniel 'Boxing' up the vault

Hard at work!

Now we are all off to bed all ready for another long day in the field.
PS - we did let Daniel out of the vault hole!

Diary of a new site build.

2011-04-04T21:37:00.000+12:00

This week we are following the building of a new National Network site Ruatahuna (HERE)

Today the team of 4 (including me!!) drove up in a GNS convoy to Rotorua, and dropped some gear out at the site in Ruatahuna, which is South-East of Rotorua via some beautiful native forest and very windy gravel roads!

Its looking to be a very wet day tomorrow as we begin the build, watch this space.....

Convoy loading up with Diesel

There were lots of horses roaming around

and it was very 'Gorillas in the Mist'

Earthquakes - Exploring our website data - Part two.

2011-03-22T11:56:00.000+13:00

Quake Drums : 101

The most common means of displaying seismic monitoring data is called a seismogram. Traditionally these were drawn by ink on paper, but today are usually created by computers using digital data.
You read a seismogram like you are reading these words; the earliest time is at the top left and then goes along the line to the end and then starts at the left of the next line. The top-left is therefore the oldest data and the bottom-right the most recent. All of our drums cover a 24-hour period.

The drums on the GeoNet website do not display 'real-time' data as the volume of data required to be sent across the internet is too great. Instead, each seismogram is produced every 5 minutes and the web page updated as each new image becomes available.

An earthquake typically is a signal that is much larger then the normal background. A nearby earthquake usually has a very sudden onset and decays away relatively quickly (usually less than 5 minutes). With a more distant earthquake you may be able to see both the P- and S-waves and the earthquake decays away more slowly. Because of the limited resolution of the seismograms you cannot always see the both the P- and S-waves, especially for nearby earthquakes.

The traces are coloured in dark blue and purple so it is easier to see which data corresponds to each line. A seismogram is coloured red if is clipped, ie. the largest parts of the signal are not shown. If this was not done then a large earthquake would obscure much of the seismogram from view. In other words, if the signal is red the real size is larger than is shown on the seismogram.

Seismograms are not all at the same scale. This is as some sites are noisier than others and tend to be plotted at a scale that shows a smaller signal (these sites have a larger scale number). To plot these sites at the same scale as nearby, quieter sites would result in a seismogram completely blue (or red) and would show no useful information.

The seismometers that we use are very sensitive instruments and can sometimes be triggered by unrelated phenomena like weather, traffic or movement of livestock.

NOTE: Not all earthquakes that are widely recorded on these traces are felt by people.

Examples:

Earthquakes - Exploring our website data - Part one.

2011-03-14T20:07:00.000+13:00

We quite often get queries (via email and facebook) wondering on how many earthquakes a particular area gets, and 'was there an earthquake yesterday' etc. and more recently we have had lots of questions regarding Christchurch! I will do a series of posts on how to find and use the data within our website which will hopefully help you answer those questions now and in the future.

You all know we get a large amount of earthquakes in New Zealand every year (we locate over 15,000!) we only put the larger/more widely felt earthquakes onto our 'recent quakes' page (or else it would be chocka!) Now we aren't hiding anything, you can access all of our data via our website! We have heaps of cool things for you to look at on our website via the 'Resources' tab, here are a couple ..

Quake Search CLICK HERE
This lets you search in a particular area, date and size of earthquake.
1 - Draw a box around the area of NZ you are interested in. (or you can put in the coordinates)
2 - Select the time frame - note. UTC = Universal time = at the moment is 13hrs behind NZ time.
3 - If you are interested in quakes of a certain size, put the magnitude in here.
4 - Output: you can choose * CSV= spreadsheet, Here you get all the guff - numbers, mag, depth etc
*Map (with or without towns) and * KML - which will open up in Google Earth.

Here is an example of all of the earthquakes in Canterbury from March 1st until the 14th:

Christchurch Landslide Response ~ Site 2

2011-03-02T15:23:00.000+13:00

The team are now at Clifton and about to install equipment on a property with very large cracks in the lawn as shown in the pics below:

In this photo you can see the temporary gps equipment set up in the background.

Andrew connecting the gps.

Christchurch Landslide Response ~ Site 1

2011-03-02T13:15:00.000+13:00

Todd and Andrew and busy installing the first of the gps sites. I spoke with Andrew this afternoon and he said this site is at Redcliffs above the slip that fell onto a school.

Todd digging a hole next to the temporary gps installed last week.

And Todd again, tinkering with the new semi-permanent gps equipment almost ready to go.

ShakeNZ Animation of the 22 Feb 2011 Christchurch Earthquake

2011-03-02T11:34:00.001+13:00

Christchurch Landslide Response

2011-03-01T17:17:00.000+13:00

Two of our team (Andrew and Todd) are gearing up to head down to Christchurch for GNS Engineering Geologist and landslide wizz Chris Massey.

The team are going to install two precision gps instruments (pictured right) at Sumner and Redcliffs landslides, to monitor potential land movement.

More info to come tomorrow!

Christchurch Rapid Response ~ The finale

2011-02-28T17:34:00.000+13:00

The team have now finished with all sensors are now in place; 6 weak-motion - as far away as Duvauchelle (at the head of Akaroa Harbour) and 4 strong-motion around the Port Hills.

Both teams are now on their way back up to Wellington. Before leaving the city, they stopped off at a welfare centre to donate all of their uneaten food.

A very weary team, all packed up and ready for the long trip home! (L-R Caroline, Charlie, Sam, Lara)

Finished site at Otuki Valley.

Christchurch Response ~ Day 3

2011-02-28T10:02:00.000+13:00

The team have two weak-motion sites to install today and then they can begin the long journey home. They are all looking forward to their own comfy beds, though I'm sure they will miss being woken up by the camper van shaking around in the aftershocks during the night!

Cool pic of the day: This is an earthquake just as the team were checking the system on the seismograph they were installing east of Tai Tapu.

Christchurch Response ~ Day 2 ~ Pt 2

2011-02-27T21:58:00.000+13:00

The team had another long day in the field, four strong motion and four weak-motion sites are now installed. Tomorrow they are off to Akaroa.

I asked Lara what her thoughts were as they were driving around Christchurch, (as we had both travelled around the city in November to distribute the 'GeoNet News Special Edition' and love ChCh) she said: "it still feels unbelievable to see an area you know looking so broken. Everywhere you see roads are cracked and you see signs for water. Like a war zone. but locals are amazingly resilient and positive and still happy to help"

Lara (with lots of gear) about to go for a hike to find a site east of Diamond Harbour. After all that lugging they get to dig!

A large part of Charteris Road has collapsed, this is on the way to Diamond Harbour.

Lara, armed and dangerous with a compass, making sure the seismograph is aligned correctly.

Caroline putting the finishing touches on the forth weak motion site, east of Tai tapu. The electric fence is too keep nosy animals from checking out the equipment!

Christchurch Response ~ Day 2

2011-02-27T10:25:00.000+13:00

Some of the team all snuggled up in their 'home sweet home' testing instruments and planning their sites for the day. Summit Road is closed so they have to relocate one of the sites they had planned.

Below is a one of our strong motion instruments (basically a lot of technical guff all housed in a grey 'suitcase' ) and below right is the temporary home, in a garage, which a kind member of the public has allowed us to use.

They have also sent through some of the now familiar sites of Christchurch, below...

Christchurch Response ~ Day 1 (+ Updates)

2011-02-26T12:34:00.000+13:00

With Team 2 travelling down from Kaikoura today, Team 1 (camper) set off this morning and have installed the first temporary site, north of the city
(you can see the site locations here: http://www.geonet.org.nz/var/storage/images/media/images/news/2011/deployment_feb/57163-1-eng-GB/deployment_feb.jpg yellow pins are short period (like in the photo left) and red pins are strong motion instruments.)

Pics to the left show Lara at the first site install of the day, and Sam in charge of the camper cooking!

PM ~ Update

Both teams have now split into two and have been hard at work all day. So far they have installed two sites each, progress has been slow due to traffic detours and hard digging. One hole the team had to dig took over an hour!

One of the many unbelievable sights the team have passed whilst travelling around Christchurch, this picture shows some houses sitting precariously on the cliffs at Sumner.

Caroline(left) and Lara (below) from today's 'girl power' team, installing a short-period sensor on the hills above Sumner.

Christchurch Response ~ Team 1 Arrive

2011-02-25T20:54:00.000+13:00

After some interesting sights on the trip from Picton, the 'camper team' have finally arrived in Christchurch.
Below are a slip just south of Seddon and a petrol station in Kaikoura.

This is the first quake damage they came across, Burwood Rd in Christchurch. The team will camp up tonight and begin deployment first thing tomorrow.

Christchurch Earthquake Response

2011-02-25T10:37:00.000+13:00

Following the devastating earthquake on Tuesday February 22nd, a team of four GeoNet technicians and scientists are on their way down to Christchurch to deploy instruments to better capture the aftershock sequence, and get a better understanding of the local fault structure. I will follow their progress and update you with photos.

Due to limited accommodation in Christchurch our team have traveling and are staying in a camper van.

UPDATE 16:00 Team one (camper) have just driven through Seddon, and Team 2 are currently on the ferry, though a late boarding means they will be spending the night in Kaikoura
before heading down to Christchurch and meeting up with the camper team.
Below - the very full GNS ute of Team 2, waiting to load onto the ferry