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West Antarctic Ice Sheet Stability:
Glacial Record from the Ohio Range of
the Horlick Mountains in the Bottleneck
Hal Borns*, Aaron Putnam, UMaine
Robert Ackert, Sujoy Mukhopadhyay, Harvard.
December 15, 2004 to February 15, 2005
January 2nd 2005

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The East Darling Moraine and Weather

Today started off somewhat clear, with a stiff breeze blowing from East Antarctica. I was up, got the snow, made hot water for the others as they emerged, and scraped off a drift that had formed in the entry to the cook tent, so the others needn’t wade.

We ate breakfast, and set a date for our camp move with AirOps via the Iridium satellite phone (we plan on being ready to move to Mercer Ridge by the 15th, if all goes well). Then we were off, it being my turn to ride on the sled. I suppose I am lucky in this respect, as being the lowest on the totem pole, there was always the possibility that I would constantly ride on the sled! Thanks to an understanding, merciful crew! Some adjustments to my attire rendered me entirely wind-proof, however. One can be entirely unaffected by wind if you put on your windstopper hat, tie the ear-flaps, then pull down your neck-warmer over your inner hat to secure it. On comes the Icelandic wool hat, and that is secured by the ski-goggles. Utilize the optional wind-breaker hood, zipped-up all the way, and no wind will penetrate! It turned out that this get-up would be put to the test later in the day…

We traveled to the first moraine we had viewed from the ice on January 2, located just south of Tuning Nunatak. Robert and Peter went to sample a bench that diagonally traversed the cliffs of Darling Ridge, hoping to find evidence for the maximum ice sheet elevation. It appears as though a bench has been carved along a joint plane all along both Darling and Discovery Ridges, thus suggesting it may have been exploited by ice. Other parallel joints could be seen above and below, but none had been excavated to the point where they formed such a bench. Sujoy suggested that this may be a sort of trimline, representing the maximum stable ice-sheet elevation. Similarly, a darker reddish color of the granite above the horizontal joint suggests it has undergone more weathering – a subtle indicator of a trimline perhaps?

While Robert and Peter were scrambling around on the cliff terrace, Sujoy and I sampled a transect through the moraine below. We sampled the crest, as well as the rocks just emerging through the ice, presented with many nice, angular erratics fitting our list of criteria to a tee.
Over the course of the afternoon, the weather began to deteriorate. Sujoy and I were blasted constantly by wind, and receiving blows from stronger and stronger gusts as time drew on. It is not easy to pin down a sample bag for a picture when the mighty wind keeps trying to whisk it off to West Antarctica! Also, every time you go to take a picture, it is as if the wind knows this, and gives you a push in some sort of playful, yet mischievous manner that makes work difficult…

When finally finished sampling, everyone regrouped at the moraine feeling quite cold and windblown. Climbing out of the windscoop, we discovered our snowmobiles half drifted in with blowing snow, as they were in the main path of the howling freight-train of wind… We dug them out, and had to perform quite a juggling act to make sure no gloves flew away while tightening up the ropes on the sleds.

We quickly got moving, but the surface definition was extremely poor so sastrugi and crevasse alike were invisible until one was perched atop the structure. I felt bad for Sujoy, who had to endure the sled ride back, with me pulling him blindly through the storm!

The wind crept to its final, constant velocity of about 30 kts. Of course it isn’t blowing the tents over, and one can accomplish a certain amount of necessary work in it, but it definitely has a tendency to take the heat right out of you. I again cleared the drift in front of the Endurance tent upon our return, and by the time we were eating supper, the drift had completely reformed…

Looking around outside during the windstorm, you could actually still see all the ridges, and further. Visibility was only obscured by low, drifting snow, however it was all snow merely being redeposited. No precipitation was occurring in this event, yet snow was certainly being focused in new areas. This makes me wonder about ice cores, and if they may be obscured by such focusing events… Regardless, the storm was actually very beautiful and intense.

Moments from today allow me to see an infinitesimal portion of the immense power of the Earth… I now count myself a firm believer in animism, and cannot help but believe that this landscape is as alive as we are, and more powerful than anything we can contemplate.

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