The Shear Zone

The most problematic area on the entire traverse route would undoubtedly be the Shear Zone. Just 30 miles from McMurdo the greater Ross Ice Shelf tries to bend its way around Ross Island. When this happens the glacial ice rips apart, forming massive crevasses.  Crossing this area is dangerous. The crevasses must be detected, assessed, and sometimes destroyed if necessary.

A Shear Zone passage can be intimidating, especially if you’ve seen pictures of how large the crevasses can be. A quick observation of the area reveals no indication that there could be a giant void underneath your feet. From the surface it looks completely flat and unthreatening. We must use Ground Penetrating Radar (GPR) to detect the crevasses.

All the crevasses are marked with 2X4 posts and some have names. There is Mongo, Strangebrew, Personal Space, Baby, Battery Crack, Baby 2, Juanita, Ten O’clock Break, Snap, Crackle, Pop… just to name a few.  And in the middle of all this chaos, there’s the ‘Miracle Mile’ where for some reason there are no crevasses at all.

Today we blasted the two suspect crevasses. We believe the snow bridging them is too thin to support the weight of our tractors. So we blow them up and then fill the resulting hole with snow.

The explosions were impressive. The first crevasse was relatively small. The second however was quite large- over 100 feet deep and 20 feet wide in places.

This is a NEW crevasse and we got to name it.  We gave it the name…wait for it… Justin Bieber. Yup. I’m not sure why we gave it that name, but Derrick keeps calling it Justin BEAVER and this annoys me.

These giant canyons underneath the snow have never been viewed before. That’s a rare thing this day and age to see something that no one has ever seen. We took the time to repel into the largest one to check it out.

Above: View from inside the crevasse looking up.

Below: A crevasse as seen with Ground Penetrating Radar

 

Camp 20

Miles Advanced: 50.1                                                                                                                                             Weather: Ice Fog, 22 Degrees

We dropped off 3 snowmobiles and a few hundred gallons of fuel at Camp 20. Supposedly a plane is going to come grab that stuff and fly it somewhere important- I’m in the dark on this one.

We crossed the ‘Shoals’ without mishap. Dosinga drove the Prinoth while Terry read the radar.

Above: Prinoth with Ground Penetrating Radar.

They did find some crevasses- the biggest one being about three to four feet wide. All of them are about 20ft below the surface which is well within our parameters to cross.

Day 17

Miles Advanced: 58.1

Total Mileage: 672.5

Elevation: 425ft.

Weather: Partly Cloudy, 32 Degrees

Location: Base of Leverette Glacier

Finally, the weather has cleared and we can see the mountains- the massive glaciated peaks remind me of the Wrangle St. Alias Range in Eastern Alaska . We passed the Axel Heiberg, Scott, and Amundsen Glaciers which fall from thousands of feet from the Polar Plateau down to the Ross Ice Shelf .

We’ve made it to the base of the Leverette Glacier, we start ascending tomorrow.

Mechanics had to do an oil change on a couple of the tractors- the oil was cold, so it took awhile- in fact they’re still working on them as I type- its 9:30pm.

Miles Advanced:25.7

Elevation:1717ft.

Weather: Ice Fog, 5 Degrees

We have a fuel tank cached at the bottom of the Leverette Glacier for Twin Otter folks.

They seem to really like this tank because we had to pump an additional 1,317 gallons into it. This took some time and kinda crushed our mojo.

We were on glare ice at that point and had trouble getting the tractors going, they kept spinning out. Also our bladders were swinging wildly back and forth and the tractors wanted to follow the bladders, so we snaked up the hill, ever so slowly.

On the way up, the welds on a D-ring tore loose- and a bladder with 3,000 gallons of fuel was nearly run over. That would not have been fun.

Other than that, I’m running out of booze.