A Comprehensive Abridged Guide to… Geology
There’s something soothing about geology. Biologists are forever worried about extinction and diseases, chemists make one false move and they lose an eyebrow, but geology doesn’t have to rush. It isn’t going anywhere. For all the impact humans can have on the natural world, we’ve hardly scraped the surface of this big chunk of rock.
And at first you might think that makes geology look pretty boring, because it’s all about rocks. Hoo-BOY are there a lot of rocks! And if you want to get into geology, you’d better like rocks1, because geologists see more silicon than a pornstar.2 But for now I’ll just cover the three basic types so we can move on:
- Sedimentary rocks: Made from little bits of stuff stuck together, like mud, or sand, or shells. This is the type where we find FOSSILS which are AWESOME and COOL.
- Igneous rocks: Ignis means fire, so these are the rocks which form deep underground (anything with big pretty crystals) or are violently expelled from volcanoes (anything with tiny bubbles).3
- Metamorphic rocks: Made by getting other rocks and just heating or smearing the hell out of them. A good example of this is marble (known for its distinct marbled pattern) and schist (known for its fairly schisty pattern).4
Okay, rocks. Check.
The second thing you realise about geology is that it covers a lot of really big cool stuff like volcanoes and earthquakes and mountains. Those guys you see in pictures standing on the edge of volcanoes? Geologists. Looking at mineral formations at the bottom of an oceanic trench? Geologists. Toasting sausages over a lava flow? Drunk. But probably also geologists.
To geologists, the planet is an active, moving thing, throwing up mountains, and smashing plates together like some kind of titanic Greek wedding. The ground beneath our feet is moving, slowly and unstoppably. We’re not standing on a solid rock. We’re not even standing on a solid rock with a liquid centre. We’re standing on a ball of liquid, with a thin, fragile crust, shifting and melting and reforming. New crust is formed in the deepest oceanic trenches, and old crust is pushed back into magma at the edges of continents. The slowest plates shift about as fast as your fingernails grow, the fastest, the speed of your hair.5 And since continents aren’t exactly smooth as silk, when you move them together, or apart, or past each other, they tend to snag a little. Just a little. And when those snags pop apart, they tend to level a city or two, and flood hundreds of coastal villages. In some ways, geologists have filled the shoes of the ancient oracles, looking for signs in their weird devices, trying to predict the whims of the gods. Fortunately, nowadays when they get it wrong they only get metaphorically crucified.
The third thing about geology, that people often forget, is that it’s where the money’s at. You want to get rich in science?6 Don’t be a zoologist, that’s all fighting loggers and begging for donations. Mathematicians are stuck in the ivory tower fighting for tenure. Chemists might get lucky and spend their lives inventing a new kind of glue. But there’s always money in the ground, if you just know where to find it. And people will pay well for someone who can find it. Oil companies, diamond mines, the entire western part of Australia7: to them, a geologist isn’t a scientist, it’s a bloodhound, trained to sniff down those valuable non-renewable resources. And the toys they employ to do that sniffing border on the science-fictional. Sonar mapping, radiation mapping, satellite density imaging… A hundred years ago, if you wanted to find gold, you had to pick a likely spot, dig down, and hope for the best. Nowadays, you can basically point a satellite at a mountainside and see what it had for breakfast.8 There’s gold in them there hills, and also what appears to be a small antimony lode, three wombats, and somebody’s contact lens.
In some ways, geologists have a lot in common with archaeologists.9 They’re the historians of the planet, figuring out what it’s been doing its whole life, what makes it tick. A good geologist would be able to tell you the history of an area just from the roadside cuttings as you drive along. But don’t let that put you off inviting him on your roadtrip, because a good geologist would also bring the beer!
And puns. Maybe let that put you off a little.10
- And puns. Oh god the puns. [↩]
- OKAY, technically silicate compounds, but shhh. [↩]
- Unfairly, the crystalline (or plutonic) rocks are often the most valuable, while volcanic rocks are really good for getting dead skin off your feet. I dunno what they did to deserve this pumicement. [↩]
- Also a rich source of puns. [↩]
- I don’t know who came up with these comparisons, but they rock. [↩]
- AAAHAAAHAHAHAHAHA. Oh, I kill me. [↩]
- I will not turn this into a political rant. I will not turn this into a political rant. I will not turn this into a political rant. [↩]
- I just remembered that I was at one point planning to study geomatics (satellites and mapping). I wonder what my alternate universe self is doing with all that money right now… [↩]
- They even work together sometimes. The geologists probably lend them money for bus fare. At this point it should be noted that I ended up studying archaeology. Sorry Mum. [↩]
- But it’s not his fault. [↩]