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Hilarity ensues – Part I

Or: Why you should do fieldwork

By Tanja

Just under a week ago I came back from a two-week long fieldwork in the bush area of Western Australia. Not sure if that area really counts as the outback as the nearest town (Esperance) was ~300 km from where we were and we were around ~800 km from Perth… I know it can get way more isolated up in the Kimberleys apparently. So anyways… before I tell you a few short stories about interesting things that happened let me tell you something about this fieldwork itself and why we went there and back again.

In seismology we collect our data by downloading a bunch of seismograms and then processing them in some way – which varies depending on what you need to extract from them. In order to have seismograms you need seismometers that will record earthquakes from around the world. There are plenty of these distributed around the globe and data is readily available.

map
Figure 1: Project area and the array in question. On this particular trip we serviced/installed all the stations shown in either half-red or full-red symbols.
Courtesy of Christian Sippl.

But sometimes you maybe want to study a specific region or a particular structure within the region – this is when you need a seismic array (usually in some shape – elongated, circular, L-shaped, spiral…). There are a lot of global arrays (one of the most popular being the moving USArray) but sometimes you don’t have arrays where you need them. And that is when you have to physically install them. One such array has been installed around ~2013 in remote regions between Esperance and Kalgoorlie in WA (Figure 1). Since then those stations needed to be serviced and occasionally more needed to be added to the array.

On this particular fieldwork I was in the role of a little (literally) helper – my job was mostly to service the already existing stations, but I was also shown how to install them. This involves fun cardio activity that is sure to get you out of the gym, out into the sun to around 40 degrees where you then dig ~1.5 m deep holes.

In the gravel!

Sand if you’re lucky.

Being already involved with a gym and several different cardio activities I had to pass on this brilliant opportunity and was required to service the stations (Figure 2) only.

Recorder
Figure 2: Recorder of seismic data. The big, black, enclosed, bulky thing is the battery. Plugged into the recorder are seismometer (buried in the ground) and a GPS antenna.
Courtesy of Christian Sippl.

This means I have to change the battery in the seismic recorder, to assure it keeps running. I have to collect the data from the recorder – in the form of an SD card, check them on the spot and make sure they are recorded correctly (for example, you can observe an earthquake on them, no components are acting strangely and are active and such) and then close the station, hide it – wrap it into green tarp and cover it in branches so the animals won’t chew on it (Figure 3) and lost humans wouldn’t mistake it for a water cooler. Then you move to the next station.

This whole service usually takes around ~15 mins in total. If something is wrong with the data you have to additionally change the entire recorder. Recorders weigh around ~12-15 kg (I think, at least that’s how it felt) and carrying them back and forth through thick bush is another brilliant cardio activity.

So anyways – that is what I have been doing for the two weeks of my stay in WA. A lot of driving on 4WD tracks (think bumps, holes, sand, fallen trees, salt lakes), traipsing through the bush with a heavy recorder (but I had a helper of my own! I will get to that shortly), trying to find the hidden station by means of a precise GPS, servicing the station, checking the data, potentially changing the recorder, traipsing through the bush back to the car and then some more driving.

It was mostly driving.

Cow_attack
Figure 3: What happens when animals (cows in this case) investigate you recorder – the tarp is scattered in the background and the cables are chewed through. This is why you need to properly hide the recorders and wrap them snugly in a tarp.
Courtesy of Christian Sippl

In the car with me was a member of our project partners called Umar. Umar is the greatest. There I said it – let’s move on now. He was the one who hauled this heavy recorder through the bush while I was carefully stepping and navigating in front of him with my GPS trying to find the station. Thanks to him and his sense of humor I had an excellent time and every time I found something hilarious – so did he. This resulted in a lot of laughs and giggles.

Let me share some of the stuff that happened in the remote areas of WA. I will try in chronological order, but what happened on which day exactly is a bit of a blur – I mean when camping in the bush (mostly) you wake up with the sun (around 6 a.m. if you have trees above you) and go to your swag around 8 p.m.

9 p.m. if you feel very lively.

Days soon become one long stretch.

So … if you are up for a daily account of my adventures in WA, you can find it here.

Seeing and listening to earthquakes

By Chops

The magnitude 6.5-6.8 earthquake to hit New Zealand near Wellington around a week and a half ago brought earthquakes back into the news. Rather than exploring the way the earth rattles and rolls or some other aspect of the science surrounding earthquakes, I thought it might be a great opportunity to explore earthquakes a bit differently. What I want to show off today are some different visualisations (and I use that term loosely here, as will become apparent) of earthquakes that people might find fascinating.

Image of a seismic trace on a drum seismograph. Photo from http://www.flickr.com/photos/nectarous/2883757076.

Continue reading “Seeing and listening to earthquakes”

Dynamics of the rotation of the inner core

By Chops

Some research came out of RSES last week regarding the rotation of the inner core, and how it speeds up and slows down. This research, made by Hrvoje Tkalcic and others, has got a little bit of publicity (http://rses.anu.edu.au/news-events/news/earth039s-centre-out-sync) and also was published in Nature Geoscience last week. In this post, I want to explore a bit of background on how we know what’s happening deep down inside our planet, how this particular research was performed and finally, what sort of significance this sort of work has.

Cutaway of the earth's interior
(Image from iStockphoto/Baris Simsek)

Continue reading “Dynamics of the rotation of the inner core”

Earthquakes and the formation of gold deposits

By Chops

Last month, a piece of geoscience made it (albeit briefly) into the newspapers: namely, the idea that gold forms within earthquakes. This was widely reported, for example ABC Science picked it up and reported it.

Gold from the St Ives Gold Mine, Western Australia
A small sample of ancient gold from Western Australia. New research indicates this gold probably formed in an earthquake 2.5 billion years ago.

Although this news seems quirky more than anything, it is of importance for finding more resources. Although gold is commonly associated with jewellery, it has an equally important role in electronics: modern computers, to name one thing, owe their abilities to gold. Mobile phones have about 50c to $1 worth of gold contained inside them, too; and hey, there’s a heap of mobile phones around these days!

Continue reading “Earthquakes and the formation of gold deposits”

Plosky Tolbachik: Pictures of fire and ice

imagesBy Claire

I absolutely love images of erupting volcanoes, especially when they occur in ice covered mountains. Any lucky for me, today’s blog post includes both of these things!

The Plosky Tolbachik volcano in east Russia has been erupting since November last year after being dormant for 35 years.

New images have emerged of lava flows from this volcano, moving through ice covered slopes. The images are quite spectacular and are making news headlines around the world. Continue reading “Plosky Tolbachik: Pictures of fire and ice”

From the archives: Seismologists can’t predict the future…but they can try!

By Mike (originally posted 22nd May 2012)

I picked up a copy of the New Scientist a couple of days ago to shorten the bus ride to Sydney, and one particular article caught my eye, an interesting piece of recent work by some Japanese geophysicists relating to earthquake prediction. The recent post by Evan about the tragic Italian quake reminds us of a sadly acceptable truth; that even in Europe with its high concentration of science and scientists, we cannot predict earthquakes. We can identify regions in which they are likely (like near tectonic plate boundaries or large fault lines) and we can assess the likelihood of a particular sized event occurring in a given time period (say, I predict one magnitude 7 event will occur in region x over 100 years). However, knowing exactly when and where a quake will occur is still about as accurate as my dart throwing ability after 4 pints of beer, or my pool-playing ability before the same amount (i.e. not very accurate).

Continue reading “From the archives: Seismologists can’t predict the future…but they can try!”

Field Trip!

Artist’s (i.e. Mike’s) impression of the Akaoa volcano.

By Evan

As this post is published, I should be sitting in the Sydney Airport, awaiting departure to Christchurch, New Zealand. Every two years, the PHD students at RSES plan a field trip to explore things of geologic interest in an area that is different from Canberra (you can only look at granites so much!)  We decided to explore the northern part of South Island, which has a ton of interesting things, including earthquake damage, volcanoes, faults, caves, glaciers, beaches, trilobites, dunite and dinosaur footprints! In the lead up to the field trip, we put together a massive 84 page field trip guide (complete with pie shop listing). Here is a description of our itinerary:

Day 1 – Akaroa, an extinct volcano near Christchurch

Day 2 – examining the damage done by the Christchurch earthquake last year, and various interesting sections through Castle Hill and Arthur’s Pass.

Day 3 – Viewing the Franz Josef and Foxe glaciers, and the Alpine Fault that cuts through the west coast of South Island Continue reading “Field Trip!”

Science on trial: The importance of science communication.

By Claire

By now I’m sure you’re all familiar with the case in Italy, of the seven people (six scientists and a former government official) who were convicted of manslaughter for failing to predict the L’Aquila earthquake that killed 300 people in 2009.

Worldwide, there has been outcry from the scientific community (and the community in general) over these charges. In essence, the scientists have been held accountable for failing to predict an event that can not be predicted. It appears that the scientists have become the scapegoats for this disaster, allowing the people affected by the quake to feel like justice has been served in some way.

Upon further investigation, the scientists have actually been charged for failing to accurately communicate the risk of a large earthquake that in this case, happened to eventuate and kill 300 people. The prosecutor’s case is built on the belief that the scientists gave out “inexact, incomplete and contradictory information”. Continue reading “Science on trial: The importance of science communication.”

Seismologists convicted for failing to predict earthquake

By Evan

I’ve written about this a bit in the past, but today, the news came down that six scientists have been convicted of manslaughter in Italy for failing to predict that an earthquake was imminent after a series of small tremors was a precursor to a major earthquake that killed over 300 people. I have to say I am a bit sad that this was not the top news story this morning (I guess people care more about the fall from grace of Lance Armstrong), given how much of a miscarriage of justice this is. This is from a country that has failed to prosecute a certain former prime minister, so perhaps this is not surprising.

I have to keep this short, due to being busy before heading off to New Zealand next week. I recommend reading the reaction from several leading experts on earthquake hazards on livescience.com. Pretty much all of Italy is at risk of earthquakes due to the collision of Africa into Europe. The damage seen in the L’Aquila earthquake is mostly the result of poor planning to reinforce old buildings that were not designed to withstand an earthquake. I think this quote from the livescience.com article sums it up well:

Evacuation is typically not the best response to these small swarms, according to a 2010 article published in the journal Geophysical Research Letters. That study found the likelihood of death for citizens in L’Aquila’s least-safe buildings was still only about one in 100,000 — a risk that’s better ameliorated by retrofitting dangerous buildings than evacuating entire towns for indeterminate lengths of time on the slight chance of a quake, the researchers concluded. (No charges have been brought in L’Aquila regarding building codes or standards.)

Satellites save lives: pack yours today

By Nick

A SPOT4 satellite image of flooding in Barangay, Manilla, The Philippines in December 2011. Image from the DisasterCharter.org

 

Normally this kind of imagery is something I’d reserve for a Not So Serious Sunday, but these satellite images aren’t just for looking pretty, they help save lives. I’ll admit I didn’t know about the Disaster Charter before listening to this slideshow. But what a great asset it is to the world. Helping to save lives by providing immediate imagery of disaster areas.

BBC News – Saving lives from space.

Continue reading “Satellites save lives: pack yours today”

Not So Serious Sunday 16

by Brendan

Volcanoes are cool, as this video describing a fissure eruption at Kamoamoa on Kilauea  Hawaii in 2011. It contains some amazing footage of a fresh eruption including some awesome lava fountains.

Tsunami Debris

Location of debris from the 2011 tsunami. (NOAA)

By Evan

Perhaps nothing is more sobering to an aspiring earth scientist than the results of major disasters. I remember watching the footage of the 2004 Sumatra tsunami and thinking about the responsibility we have to the public to inform about the hazards associated with natural phenomena such as earthquakes and tsunamis. The last major megathrust earthquake that produced a large tsunami before the Sumatran event was the 1964 Alaska Earthquake, which caused few fatalities due to its remote location. People were unaware of the risks in Sumatra, partially because this style of earthquake does not happen frequently, and there had been few geological investigations to determine the risk there.

In Japan, there is a long recorded history of major tsunamis. However, the sheer size of the earthquake that struck there last year was unprecedented in the past 1000 years, and barriers that were designed to handle historically large tsunamis were insufficient. As a result, there was a massive loss of life, and large amounts of debris were swept to sea. The New York Times is reporting on a vessel carrying volunteers who are documenting the debris that was swept to sea. This project is of archaeological interest, and to determine what might be coming towards the North American coast. People on Haida Gwaii on the west coast of British Columbia are already describing the beaches there as “landfills”. As a goodwill gesture, the Japanese government is offering to help pay for the cleanup, which is probably going to be an immense endeavour. Continue reading “Tsunami Debris”

Another Mars Lander Announced

by Brendan

Artist rendition of the proposed InSight (Interior exploration using Seismic Investigations, Geodesy and Heat Transport) Lander. InSight is based on the proven Phoenix Mars spacecraft and lander design with state-of-the-art avionics from the Mars Reconnaissance Orbiter and Gravity Recovery and Interior Laboratory missions.
Credit: JPL/NASA

Hot on the heels of the landing of the Curiosity Rover, NASA has announced plans to send another mission to Mars in 2016, and it has a very strong grounding in geophysics. The mission, known as ‘InSight’, will focus on the internal structure and thermal nature of the planet. The lander will have two main instruments, a seismometer, which will be used to measure seismic activity (Marsquakes) and a heat flow probe capable of drilling down approximately 5 metres to obtain long term measurements of heat flow.

One of the big scientific questions around Mars is whether it has any sort of plate tectonics and if not, why not? Continue reading “Another Mars Lander Announced”

Pumice island found off New Zealand

An area of floating pumice 250 nautical miles in length and 30 nautical miles wide in the South Pacific ocean. Picture: AFP / New Zealand Defence Force

(Story from News.com.au)

A giant floating island of pumice was created when a previously dormant volcano erupted amid more than 150 earthquakes over two days last month, scientists say.

The eruption of the Havre Volcano, about halfway between New Zealand and Tonga, is believed to have caused the 7500 square kilometre pumice “raft”, which was encountered by a New Zealand navy ship last week. Continue reading “Pumice island found off New Zealand”

Mount Tongariro erupts!

By Claire

Ash cloud over Ohakune.

At around midnight last night, Mount Tongariro, on the North Island of New Zealand erupted.

There are reports of ash in the area immediately surrounding the volcano, however, there have only been small amounts of lava ejected during the eruption. Scientists believe that the eruption was driven by hydrothermal processes, rather than through the build-up of lava.

Ash in the area surrounding Mount Tongariro.

The eruption comes after 3-4 weeks of volcanic unrest, including a large number of small earthquakes, leading up to the eruption. At present, there is no indication that the volcanic activity is escalating.

Follow all of the updates on the One News website.

Victoria- on the move!

A fitting slogan
Source:www.ozbargain.com.au/node/41123

By Kelly

Once again, local earthquakes are dominating the morning news. Yesterday evening  a magnitude 5.3 tremor shook southern Victoria, with the epicentre located 9.9 km beneath Gippsland along the state’s south coast.  The largest felt in almost 110 years. Geoscience Australia (GA) has reported that around 60 aftershocks have been felt in the region since and that tremors may continue for the next week. GA seismologist David Jaspen has attributed the seismic activity to the compression of the Australian continent due to the motion of plates around the Pacific region. When speaking to The Age this morning he said:

‘‘that compression leads to a building of stresses within the earth’s crust. Once that stress exceeds the strength of the rock, it will break and release energy. That’s how we generally see earthquakes occurring in Australia, a build up and then pop.”

Continue reading “Victoria- on the move!”

Seismometers in schools

Natalie Balfour looking rather pleased with her seismometer

By Kelly

In a previous post I took a peek at the career trajectory of Dr Natalie Balfour -seismologist and geosciences educator extraordinaire. Natalie is the coordinator of the “Seismometers in Schools” program, which was launched last week at Melrose High School here in Canberra. This week I’d like to follow up with more on the program itself, and why it is an incredibly effective tool to engage young scientists in the Earth Sciences. An idea that is very much in line with a certain blog I know…

“Most seismology lends itself to high school classrooms, particularly when students are learning about the physics of waves, whether it be sound or light” says Natalie. The idea of placing scientific equipment to measure seismic waves is not new, with successful programs run previously in the U.K, the U.S and in France. Students use data collected from their own seismometers to learn about wave properties such as frequency, wavelength and amplitude. However these seismometers are no toys. Display software produces seismographs allowing students to actually apply the fundamentals of maths and physics to their surrounding (and not so surrounding) environment. With the right filtering, this equipment has been able to pick up earthquakes as far as Chile, and even the recent earthquake in Italy! Continue reading “Seismometers in schools”

“Nat”ural Hazard

Map of potential sites for AuSIS instruments (red) and existing sites in ACT (yellow). The location and number of stations per state will change depending on school response and logistical considerations. Source: http://rses.anu.edu.au/highlights/view.php?article=221

By Kelly

Our Research School of Earth Sciences has a plethora of talent, tucked away in the many corridors, labs and lecture theatres. This kind of environment can foster a well-rounded graduate (or blog follower) if you actually take the time to go to the many seminars, or talk with your colleagues (or read the blog). Seismology has made it into the news, and into this blog on a number of occasions recently. So with these things in mind, I set off upstairs and was lucky enough to talk to one of our very promising and inspirational early career researchers about her current work. I say lucky as I thought I was busy, however I look positively sluggish next to Dr Natalie Balfour.

Natalie is a post-doctoral fellow in seismology with the Earth Physics group. Her position is a little different from most as she is not only a researcher – she works on the source mechanisms and rupture models for earthquakes in Indonesia – she is also coordinating the Australian Seismometers in Schools Network. And so, her position is funded through a combination of a joint linkage project with AusAid/ARC, the Australian Governments Overseas Aid Program and the Australian Research Council, and AuScope, an organisation for a national earth science infrastructure program. So how does one end up being a seismologist leading the coordination of national educational programme? Continue reading ““Nat”ural Hazard”

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