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Words With Rocks

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


The first thing geology ever said to me was, "Ouch!"

I was five years old, and Mount St. Helens was busy erupting all over my teevee. I made it a get well card. It looked like it hurt. Thus began an ongoing conversation between me and objects people tend to think of as inanimate until they explode, rip apart, or fall down.

You'd think, growing up in Northern Arizona, that the Grand Canyon would have been my gateway drug for geology. Not so. Yes, it's grand. Yes, it's gorgeous. Yes, it has volumes to tell us about geological history. But we saw it so often before I'd learned the language of rocks that it became that huge hole in the ground we had to go see every time relations from the Midwest visited. Volcanoes were different. Watching those roiling gray clouds of ash pour from St. Helens, having some of that ash placed in my thrilled young hands by neighbors who visited the volcano shortly after its May 18th eruption, connecting her to the volcano that loomed outside my back door - that hooked me. That event taught me that geology matters. St. Helens gave me a volcano phobia, and then cured it. St. Helens taught me to extrapolate from the present to the past, a major tenet of the science of geology.


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I'm here, talking to you about talking to rocks, partly because a volcano blew out sideways, and fifteen years later, I turned to look at another volcano I'd known my whole life and saw the same lateral eruption rip it apart thousands of years in the past. "What happened to me," St. Helens said, "is exactly what happened to them. Your San Francisco Peaks were a peak before that day. Oh, and it would've been a really bad idea to stand where you're standing now, what with the lahar and all."

I just stood there with my jaw agape, looking from the lahar deposit to the gash in my beloved Peaks, sputtering the occasional overwhelmed expletive as the thrill of realization and the enormity of what had happened pinned me to ground that was perfectly safe for the geologic moment.

This is what I want to give you, my dear readers: the indescribable euphoria that comes from understanding a place for the very first time. Those stones you glance at as you pass, those nondescript little brown and gray rocks that seem hardly worth noticing, are Rosetta Stones. They speak, and we're learning their languages. They're storytellers and guides, sometimes bearing fresh tales of events that happened only yesterday, sometimes transporting you into deep time. A few of them have stories of other worlds. Those little unregarded rocks have important things to say about how the Earth works, and where its dangers and refuges are. They tell us where it's safe to build and where we'd best not. They give us insight into layers of the Earth we can't see directly. They trap carbon and act as aquifers. They allow us to reconstruct past climates and get an idea of where the present one is headed. We extract wealth from them, energy, rare earth elements without which computers and smartphones wouldn't work. There's geology in your iPhone, and it's not just the app you may have downloaded for determining strike and dip in the field.

Geology has a practical bent. I've known this all my life, of course: I'm a coal miner's daughter. All right, so technically, he's an engineer and didn't dig out the stuff. But he worked at a mine, took me to see it as a young girl, and made it impossible for me to see coal in my stocking as a threat. Like most people, I thought he was digging up dinosaurs to light our houses. The truth is so much cooler than that: swamps and lush deltas, full of exotic plants and trees, were buried and became metamorphic rocks that burn. The economic importance of coal can't be minimized: ancient plants fueled our Industrial Revolutions. Now that we're beginning the Green Revolution, we can stop removing mountaintops and filling our atmosphere with ancient carbon, and get on with enjoying the stories those metamorphosed forests can tell.

I grew up on the Permian Riviera. A lot of people joke about oceanfront property in Arizona: baby, I had it. So the oceans had been gone for hundreds of millions of years. So what? With geology, the past becomes present. A lot of people come to Sedona for the vortexes and vibes and crystal magic. I come there for the lithified beaches. You can be in the middle of some of the driest country in the world, enjoying sea breezes. And while other folks talk about how many miles they walked, we adorers of the good science of rock-breaking talk about how many millions of years we've passed through.

Geology does bizarre things to your sense of time. It's like becoming a Time Lord. A million years is mind-bogglingly large to most folks. For us, it's barely an eyeblink. Volcanoes that have been around hundreds of thousands of years before the first human cities are young upstarts, most of them with no staying power. The Ice Ages changed landscapes dramatically, leaving the hills Seattle is built on, carving out deep lakes and sounds, coating the landscape in thick deposits of outwash and till, and leaving enormous deposits of windblown soils that feed millions. They also plucked up maclargehuge boulders and left them sitting tens and sometimes hundreds of miles away from home. But in a few million years, you'll barely know those ice sheets were there.

They're dramatic while they last, though. I first made friends with glacial landscapes in 2000, when I came up to Seattle for a research visit. I headed down to a place I'd set a scene in, Discovery Park, and fell madly in love with the South Bluff. I vaguely suspected then that each thin layer might have a story to tell, but I didn't get to hear it until years later, when I'd moved up here and pursued my fancy for geology in earnest. Everything here speaks of ice, from the sharp, glacier-carved peaks of the Cascades and Olympics, to the low rolling drumlins of the Puget Lowland. It's more beautiful than you can imagine, gorgeous enough to forgive the long winter rains. But it pays to know geology well. Build in the wrong place, and your lovely house overlooking the Sound will, after a good soaking rain, end up underlooking the Sound. Things come slip-sliding down round here all the time, because building on glacial sediments is only marginally better than building on sand. Compared to the Lawton Clay, sand sometimes looks like an excellent choice for a foundation.

And that's even before we get to the fact that the glaciers just put the icing on the cake, so to speak. Our scenery owes quite a lot to the subduction zone right off the coast. Yes, the one that will someday let rip with an earthquake that will allow us to experience Japan's March 2011 catastrophe at first hand. Yes, the one that's created our dramatic and often overly-exciting volcanoes. The geology round here that doesn't speak about continental glaciation is busy babbling about subduction zones and all of the antics they can get up to, and if we choose to stick our fingers in our ears and squeeze our eyes shut and pretend we can't hear it, we're all going to be in for a nasty shock someday.

You'd be surprised at what your local geology might tell you, if you take a moment to give it a listen.

And no, it's not all gloom, doom and despair. Sometimes, it's a nice, silent day on the deep ocean floor. Sometimes, it's a quiet craton, with pretty streams and forests and the occasional dune field. Geology has a full library - it's not just thrillers.

A lot of folks don't think they can read the rocks. They think geology's hard. They stopped at the basics they learned in school: they can recognize a volcano, and maybe tell an igneous rock from a sedimentary one, and they know vaguely what the San Andreas Fault is. They can, in a sense, point to a few items on the menu and exchange a few words, like "Hello, how are you? My aunt's pen is on my uncle's table. Goodbye!" And they think they'll never, ever be more fluent than that. They believe they're doomed to conversations about menu items and pens for the rest of their lives.

You, dear reader who has gotten this far, may be one of those people. And you're afraid, from what you've seen so far, that I'm going to whip out words like ophiolite and allochthonous and clastic detritus, and you won't have any idea what I'm talking about. You'll never learn the lingo. That's for experts, and you're going to flee the very second I bring up papers with titles like “Revised ages of blueschist metamorphism and the youngest pre-thrusting rocks in the San Juan Islands, Washington.” (Coolest geology paper I've read this year, btw, though the year's still young.) "But, Dana!" you howl as you prepare to sprint in the general direction of away, "I'm no expert!"

Well, truth be told, neither am I.

I've had exactly two classes: Geology 101 and Physical Geography, taught by the incomparable Jim Bennett. I've read a ton of books on various aspects of geology written for layfolk. And I've roadtripped through and lived with utterly fabulous geology. That got me started. I did up a few posts on all of the nifty geology my intrepid companion and I had seen in our rambles, and then got adopted by the geoblogosphere.

I told them I wasn't a geologist. They said, "Malarkey." I told them that no, seriously, totally not a geologist, just an amateur who writes about geology, and they had words with me. Many. Words. These are folks who carry rock hammers around. I refuse to argue, although I, too, carry a rock hammer. They're faster on the draw than I am.

And you know what? They're right anyway.

You don't have to get a PhD to learn the lingo. You don't need years of training to make it through a geology paper, and enjoy it. What you need is to have got out there and looked at some rocks, read some books, talked to some geologists, got out there and looked at some rocks with geologists, and read some harder books, and blog posts by geologists, and then suddenly one day you're dipping your toes in the scientific literature and going, "Hmm. Tingly." And I promise you won't even need all that here in these pages. I'll 'splain as we go along, or at least sum up. Before you know it, you'll be out in the field with a rock in either hand, saying things like, "This one's gneiss, but this is the schist!"

Puns, I'm afraid, are practically a requirement.

Stick with me, and you'll come to know geologists like Anne Jefferson and Chris Rowan, Brian Romans and Silver Fox, Evelyn Mervine and Ron Schott, Helena Mallonee and Ryan Brown, Michael Klass and Ellie Goeke, Cat and Gareth Fabbro, Callan Bentley and Jessica Ball, Ellen Morris Bishop and Dan McShane and Wayne Ranney, and so many others, people who know what the rocks say and how to translate. These folks turned me from a mildly-interested amateur into a person who drools at the sight of a new technical paper. These folks can strike stories from stones that will leave you with your jaw hanging agape, awestruck by the immensity of time and the amount of information we've managed to coax from the rocks.

And you'll meet Lockwood DeWitt, who is, hands-down, the best geology teacher I've ever had.

You'll be spouting phrases like "metamorphic facies" with the greatest of ease. And it won't hurt a bit. Unless you're spouting them whilst bashing away at a rock which demonstrates metamorphic facies without wearing eye protection, but you'd never do that because eye protection is key and you'll know that, too.

Come along, my darlings, and join me round the rocks for some rip-roaring good tales. Then head on over to David Bressan's place for the history of geology, which is just as fascinating as its present. And join me in the cantina at En Tequila Es Verdad for the after-party, where I'll still be serving serving up cocktails. On the rocks, of course!

 

Right. That sums me up, and gives you some sense of what Rosetta Stones is all about. But it's really all about you guys. Storytellers, whether lithic or biological, need people to tell stories to. So please do take a moment to introduce yourselves. Let me know what your interests are. If there are any particular geologic locales or concepts you'd like to see explored here, put in a request. I don't always have time to answer comments directly, but I listen, and do my best to deliver.

Over to you, my darlings.