Pain in the Crevasse | Continent 7: Antarctica

Okay team, let Mark the shear zone, so come on nice and close behind us. Thank you. The RAS shelf team has traveled about 30 miles, and they're facing the most dangerous part of their traverse.

Oh, we're just about to enter into the shear zone here. We just want to make sure that everybody's capable should the worst possible case happen. The shear zone looks like a safe patch of snow, but like Mount Erebus, it's full of hidden crevasses. For as benign as it looks, there's a lot going on. One side, we've got sort of the McMurdo Ice Shelf, and the other is the Ross Ice Shelf. It's where two large kind of ice masses are coming together, much like a river comes together.

The reason it's called a shear zone is because there's kind of a shearing effect between the two, so it's quite an active area. Interesting spot. The shear is an intimidating area, around about 6 or so kilometers, that have a number of significantly large crevasses in them. We know that there's a route through there; we really reduce that speed down even further so that we're 100% sure what we're driving on is good to drive across. Just keep a little extra following distance. How far do you want? Maybe 50 meters.

We're just going to be going a little bit slower through here, and if we stop, you should too. We're just going to get all our gear prepared for crevasse rescue. Proceed with caution. Fingers crossed.

Crossing the shear zone should take a few hours, but Tom and Rob have been preparing for it for weeks. So this is the radar boom for our PB 100, and we'll be fitting a GPR unit, a ground penetrating radar. We'll be able to see on the monitor when we're approaching crevasses, and that'll enable us to not drive into them.

State-of-the-art technology—real key piece of this whole project for this year and going into the future as well. So yeah, just got to get it up and running. The boom stretches 24 feet ahead and connects to a screen that shows ice composition up to 49 feet deep. Bends in the lines indicate empty space under the snow. Some of the crevasses through here would literally swallow this whole vehicle and probably the two trailers behind it.

So if we hadn't looked at the radar imagery and we actually just carried on, dropped into a crevasse, it would probably be all over.