A new rock discovery in the United Kingdom may turn the science of petrology on its head. Scientists are baffled, experts befuddled and the public bewildered. Despite and because of this hysteria, I hereby present the first petrographic description of chocolite.
It’s a new episode of the podClast! In episode 7 we discuss really old sponge biomarkers in rocks from Oman, Palaeomagnatism, geology on Google Earth and more. This is the first episode in 7 months and it’s the longest podClast ever, so put down you rock hammer, lift a glass of something cold and listen to the banter of the geoblogosphere.
On page 40 of his notebook M, written after the voyage of the Beagle, Charles Darwin scrolled the following:
I a geologist have illdefined notion of land covered with ocean, former animals, slow force cracking surface &c truly poetical (V. Wordsworth about science being sufficiently habitual to be poetic)
Darwin defined himself as a geologist. His seminal publication On The Origin of Species relied on what would later be known as the Theory of Plate Tectonics in order to geographically isolate and then force adaptation in species. (You can try and read Darwin’s hand written notebook M here or read the plain text version here).
So from one geologist to another, happy bicentennial Charles.
Sandra Herbert has written a book called Charles Darwin, Geologist, which is definitely on my “to read” list between now and the 24th of November, the sesquicentennial of the publication of “Origin”. Which I should probably read through again before that date too. If you’re up for reading through some superb 19th century scientific literature, On The Origin of Species by Means of Natural Selection (here’s the pdf) can be read at Darwin Online (or at Google Books), along with all of Darwin’s other works (and there are plenty).
As Andrew from About:Geology just tweeted, geologists seem thin on the ground on the micro-blogging site Twitter.
I was aprehensive to join at first, but now I’m tweeting up a storm, as too are Dave from Geology News (even Geology News tweets), Brian from Clastic Detritus, Maria from Green Gabbro and Ron from Ron Schott’s Geology Home Companion Blog. So there’s a few of us out there.
In addition to us geobloggers, there’s the likes of The Bad Astronomer, Phil Plait, super biologist PZ Myers, Skeptic’s Guide’s Rebecca Watson, NASA’s Mars Rovers and the good old USGS. Plus many, many others.
So if you’re a geologist and you’re not twittering, give it a go. If you are a geotweeter and I’ve missed you out, let us all know below in the comments and we can be all atwitter about our precious rocks.
This post is a little negative, sorry for diverging from my normally cheery posts.
I’ve been in Australia for a week now (Perth in Western Australia). The one thing that’s been made clear is the job market here for geology graduates, even with post graduate qualifications like me, is dire. If you’re a geology graduate planning on making the trip to Australia with the hope of getting a job, cancel your plans. Or at least postpone them for 6-9 months. After a solid week of plugging away looking for a job, knocking on doors, hitting up recruitment companies and applying for jobs online, I’ve had absolutely zero positive feedback.
The only work that is going seems to be going is for senior geos with 3-5+ years experience in mining. If you’ve got years of experience in mining, as long as it’s got nothing to do with nickle, then by all means make the trip to Aussie, and you’ll have your pick of jobs.
I’ve probably chosen the absolutely worst time to move country in order to get a job. Firstly, being a student for so long made me forget that people don’t tend to employ people this late in the year. With only 6ish weeks until christmas, there’s little to no chance for a graduate like me to get a reasonable position. The other thing that’s causing me and many others so much trouble are the deepening financial problems that are affecting the globe. The mining industry seems to run on credit, and since there’s little easy credit around, there’s very few new jobs.
So I’m resigned to keep on plugging away at the market. Using the shot gun approach. Hopefully something will come up. If I haven’t found anything in the next 3 weeks, I’m simply going to go home. It’s absolutely pointless trying to find work in December. Sigh.
Just another one of life’s adventures. I wonder if I’ll learn anything from this one : ) (Had to have one smiley face, or the whole post would just be a depressing mess).
On Friday the 24th of October I handed in my MSc thesis, the final title of which, was:
Tracing the origins of refractory inclusions – the Solar System’s oldest solids – a petrographic, geochemical and 26Al-26Mg dating study of CV and CK refractory inclusions
…which I’m sure you’ll agree is a horrendously long title, but does describe what the thesis was about. In short, rocks from space, what they’re made of and their relative age. I’m pretty happy with it, even though there were a few last minute things I may have liked to have been a little less rushed. But I’m just happy it’s done.
What that means is I’m now out of school for the first time in almost 6 years. It also means I’m ready to start my career as an actual geologist. As Murphy or Fail Blog would dictate, I’m entering the industry at the exact time when the market has decided to implode. But far be it from me to give up in the face of other people’s problems, so on Monday I’m flying from the relative safety of my island archipelago to the Australian continent – where everything is poisonous.
It’ll be Perth to start with, but depending on the jobs, I could realistically end up anywhere on the Australian continent. I’m a little worried as I had a call today from a recruiter that’s been looking out for jobs for me. Looks like geo grads aren’t in as high demand as they were mere months ago, so it’s going to be tough. But that’s part of the adventure, right?
In a geological context, I’m going from incredibly young geology (remember I study the oldest of the old rocks), with 200 Myr old greywacke basement overlain with loess from the last glacial maximum, to rocks which are commonly 500 million to 4 billion years old:
Image from Geoscience Australia. And I’m not too confident of the upper limit of the Archean basement in this image – since that’d imply Australia formed just 7.2 million years after CAIs. Which it most certainly did not.
That kind of age jump is incredibly cool, as I really like old rocks. So even as I’m stumbling around the streets of Perth, jobless, penniless and desheveled, I can take comfort in knowing there’s some interesting geology around, underwhich I may be able to shelter until morning. (note: that scenario probably won’t play out).
In the mean time, I’ve got posts to write and my life to pack up. If anyone out there has advice on the Aussie mining industry, it’d be awesome if you let me know in the comments below. Enormous life changing events, here I come.
The unprecedented threat of alien geology must weigh heavy on the minds of human Earth geologists. This month’s Accretionary Wedge (issue 13), opens the alien riddled can of worms that is Geology in Spaaaaace.
My previous post on the 4.28 billion year old gneiss from the Nuvvuagittuq greenstone belt mentioned that the 146Sm→142Nd isotope system was a bit unusual and that absolute dating would need to be done. This is my attempt to explain why.
A recent Science Paper (as reported by Nature and Science Centric) has dated rock samples from the Nuvvuagittuq greenstone belt, on the eastern edge of Hudson Bay in Quebec, Canada, at a staggering 4.28 billion years old. The research team used the (somewhat unconventional for terrestrial dating) 146Sm→142Nd isotopic system, due to the lack of zircon being found within the rock. This means the date will have to be confirmed, preferably with zircons, for many to lend weight to the claims, but all the same, this is an amazing discovery.
It’s pretty staggering how old these rocks are. So let’s put it into perspective:
These rocks were formed 270 millions years after the Earth (4.55 Ga), which means they’ve remained reasonably unchanged for almost the entire history of the planet. They’ve survived 4.28 billions years of: plate tectonics including subduction and obduction, glacial erosion, meteorological erosion, chemical erosion, chemical alteration (maybe), or any other method of rock recycling. It also means we have pushed back the earliest date for continental material existing on Earth by 250 million years (the previous record was 4.03 Ga for the Acasta Gneiss, also from Canada).
These aren’t the oldest terrestrial material ever discovered, however. That title still belongs to zircons from the Jack Hills in Western Australia, that have been dated at a positively geriatric 4.4 GYr. But as a sample of rock, this is pretty exciting so far as early Earth chronology goes.
Geological timescale thanks to Chris Rowan at Highly Allochthonous.
Splash image to the left lifted from Nature, and courtesy of AAAS/Science.
Hi everyone.
Just a reminder that posts for the Accretionary Wedge #13 are due this Thursday (or Friday), your time (25th or 26th of September). Check out the original post for submission details and get those little space themed articles rolling on in!
You may also want to check out the upcoming and previous hosts of the Accretionary Wedge here.
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