Callan at NOVA Geoblog has a new meme going:

What are ten things that every geology major ought to know about? The only restriction is you’re not allowed to list anything that has already been listed by a previous geoblogger. You don’t have to list everything, just ten important things

Mel at Ripples in the Sand has added to the list (both can be seen at the bottom of this post) and now it’s my turn. Embarrassingly I know nothing of “Pedogenesis” or “How aquifers work” as listed by Mel, but this is all about brushing up, isn’t it? : )

Here’s my list of 10 things every geology major should know:

1. The difference between absolute and relative radiometric dating.
2. Uranium-lead dating and how each element on the uranium 238 decay chain interacts differently with the environment.
3. The difference between a continent and a tectonic plate.
4. The properties of felsic, intermediate and mafic lava types.
5. How and why the melting temperature of a rock changes depending on the the concentration of volatiles therein.
6. What an ophiolite is and the significance of very old ophiolites.
7. The structure of the deep Earth (the upper and lower mantle including the MoHo and other zones)
8. The biological explanation for the formation of banded iron formations.
9. The insignificant difference between a volcanic sill and a volcanic dike.
10. How to spot changing environments in a stratigraphic column.

I could go on, but those seem pretty important. Below are Callan and Mel’s lists

Callan’s list:

1. The relationship between cooling rate and crystal size in igneous rocks.
2. The fact that rocks can flow, given sufficient temperature and pressure [and low strain rate, for the purists out there].
3. The idea that sedimentary rocks reflect specific depositional settings. By studying modern depositional settings and the sediments they contain, we can interpret ancient sedimentary rocks in light of the conditions under which they accumulated.
4. The fact that the chemical stability of molecular configurations (minerals) changes with different temperatures and pressures (metamorphism).
5. Large Igneous Provinces, and their potential role in tectonics and expressing mantle plumes.
6. Elastic rebound theory for the origin of earthquakes.
7. The notion of partial melting, and its relationship to Bowen’s Reaction Series.
8. An understanding of the carbon cycle, and an understanding of the atmospheric physics that facilitate global warming.
9. The role that rivers play in shaping the landscape: nickpoints, terraces, quarrying, abrasion, drilling of potholes, etc.
10. The Earth is 4.6 billion years old, which is extremely old in comparison to human life — and the reasons we think it’s so old [Pb isotopes, etc.].

Mel’s list:

1. Evolution.
2. Evidence for plate tectonics.
3. That fossils (and trace fossils) can provide more information about the rocks they reside in – depositional environment, chronology and correlation, water temperature, stratigraphic up, relative rate of deposition, water depth, etc.
4. And vice versa, the rocks can tell you a lot about the fossils that are contained within them – geography, taphonomy, chronology and correlation, etc.
5. The relationship between sediment production –> sediment transport –> sediment deposition.
6. How to identify minerals.
7. Differentiation and fractionation and how they apply to the planet, the solar system, and isotopes.
8. How aquifers work (or don’t work if we drain them too quickly).
9. Where our energy supply comes from. All facets from petroleum products, to solar radiation, to conductive metals extraction, etc. (These are also useful for seeking gainful employment as a geologist.)
10. Pedogenesis. How it takes thousands of years of chemical reactions and transport to generate the soils we use for agriculture. (And how we should be taking better care of them.)

2009-03-16 | by Chris | Comments (7)

2009-02-25 | by Chris | Full Article | Comments (4)

2009-02-25 | by Chris | Full Article | Comments (11)

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).

2009-02-12 | by Chris | Comments (1)

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).

2008-11-10 | by Chris | Comments (6)

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.

2008-09-26 | by Chris | Comments (3)

2008-06-26 | by Chris | Full Article | Comments (6)

2008-06-26 | by Chris | Full Article | Comments (4)

American Dad encounters the Langley Falls Town Geologist. Without doubt the most accurate portrayal of a geologist yet seen on screen. And the breakfasts? I’d call them outstanding!

2008-06-20 | by Chris | Comments (4)

2008-05-11 | by Chris | Full Article | Comments (4)