Hello!
Right. So, one question that you, the Internet Reader, may have is, "How does ice core drilling actually work?" I know I had that question, and this is supposed to be my job.
It turns out it's simple, really. We have a big drill and we core ice with it. "Oh, great. Thanks, Brad. That was really helpful. You're really good at blogging." Calm down. You want more details? Fine.
There are three of us on the drilling team, Mike The Driller, Dom (a graduate student at Dartmouth), and myself, Brad (I'm a graduate student at the University of Washington). Mike drills, Dom and I help him as we can, and look after the ice cores (the precious!) when they come out of the ground (which is in fact ice as well). Let's set the scene a bit. The drill is set up inside a giant dome tent so that we are minimally deterred by weather. The tent is pretty impressive, over 10 feet high, made of a lattice of orange and blue hexagons and triangles stitched together into a nylon hemisphere. The sun glows through it which makes it like working in a giant stained-glass bubble with "Mountain Hardwear T" occasionally emblazoned on the side.
The drill itself is surprisingly simple looking. There's a triangle base resting on the snow floor of the tent. Bolted on to that is little motor and bicycle chain leading to a winch with about 1200 feet of wire cable all spooled up. The cable leads up one side of a big tower arm that rises just overhead. At the top of the tower a big wheel guides the cable back down the other side where the core barrel hangs. The winch can lower the core barrel up and down the hole we're drilling.
The core barrel is a long silvery, (mostly) hollow tube about 2 meters tall. At the bottom are the three cutters, super sharp and about the width of your thumb (which also happens to be the thickness of the wall of the barrel! Good to know!). The barrel rotates in a circle about its long axis (driven by another motor). The cutters, resting on the bottom of the hole, shave off the ice in a ring. Inside this ring is a core of undisturbed ice; that's what we're after! The hollow barrel bores its way into the ice like this, encasing the ice core.
You might imagine drilling to be a loud and smelly operation. But our whole camp is run off of a wind turbine and a few big solar panels. The drill just has a couple of electric motors. So it's all pretty pleasant really.
Watching Mike drill is pretty impressive. He has a few switches and dials to play with. He watches a little digital dial showing the depth of the drill intently. He can feel the drill humming through the cable 500 feet below us. Like everything I suppose, there's a bit of art to drilling, a bit of science, and a bit of random chance.
Once we've drilled about a meter, we put the winch in reverse and pull the whole thing, encased ice core and all, back up to the surface. In case you're wondering, right when we start pulling up, spring loaded blades dig into the ice core to break it off and hold it in the barrel for the trip back to the surface.
When the barrel comes back up with the ice core in it, the whole tower arms rotates horizontally so we can easily pull out our prize. The cores are three foot long cylinders about the width of your coffee mug, and pretty heavy. They're rather delicate and susceptible to contamination once they are on the surface so the goal is to get them somewhere safe as quickly as possible ("My god, don't drop it!"). Dom and I measure the length, width, mass, take note of anything awesome, like ash layers, staple it all up in special bags to keep them clean, and place them (carefully!) into super insulated boxes which we burry in the snow for safe keeping.
The whole process of drilling and measuring takes about 10 minutes. Then we send the drill back down the hole again. Over and over, until we reach bedrock which is about 200 meters down. Our team gets into a pretty good rhythm; each doing a little task in the right order. We become very mechanical. All the while we must be very careful to not accidentally drop something down the bore hole, like a tool or an ipod or something- it's a long fall and really hard to get anything back up. Everything small in the drill tent is now tied to something.
Yesterday we drilled to 151 meters depth! We're doing very well and should be done with the first core soon. Then we'll drill a second right next to the first. On the 10th of June, two freezer trucks will arrive in Talkeetna, AK. We'll send all our precious cores out (first by helicopter, then small plane) to town. Then those two trucks will drive them to the National Ice CoreA cylindrical section of ice removed from a glacier or an ice sheet using a specialized type of hollow drill. Enter the definition here. Lab in Denver. And that's the whole show.
I'll leave you, dear reader, with a few scientific and not-scientific observations of our drilling operation here on Mt. Hunter.
Ice is heavy. We can fit about 15 core sections in a box. That makes the boxes about 150 to 200 lbs each. This is a great way to hurt your back.
Altitude does strange things to the human gastrointestinal system. In addition to the High Altitude illnesses that Seth mentioned in a previous post, I'd direct the interested reader's attention to HAIF.
The half-life of a box of Oreos seems to vary inversely with our time spent in the field as well as altitude. The result is a highly non-linear decay rate. You might think that a box of said cookies that was on the cook tent table at breakfast (yes, breakfast!) would be there at lunch. Nope.
The drill seems to prefer classical music. The drillers are more open minded.
This is an astoundingly beautiful place to work.
For a group of scientists, we're pretty superstitious apparently. “We've had pretty nice weather so far!" "You fool now we're doomed!" "If we keep up this rate will be to bedrock the day after tomorrow!" {Everyone scrambles to knock on some sort of plywood or something}.
The "Complete Sherlock Holmes" is apparently a remarkable (and enjoyable) physical example of Zeno's paradox. Despite that I read it constantly, the end appears unattainable.
We arranged our camp and built snow fences and walls all in preparation of the storms that would surely blow from the West. Surely. How clever of us. All the storms here have come from the East. Naturally.
Well, that's it for now Internet Readers. Carry on. Cheers, Brad
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