Sunday, November 25, 2007

Reflections from Granite Harbor

In my last blog, I shared information with you about the science conducted at the Mackay Sea Valley Seismic Survey. It was a very successful field season, and great information was learned about the subsurface rocks – to help us plan for the next drilling season.

This blog will share the personal experience of that same trip. I had anticipated this experience for quite some time, and was overwhelmed with excitement when my chance finally came to head for the field.

I flew out of McMurdo on November 12 in an Huey helicopter. I arrived at the helicopter pad two hours early, even though I only needed to be there half an hour early for my safety briefing. I flew out with Ken, another ARISE participant, and Thai, the mountaineer for the final leg of the field season in Granite Harbor. We were flying to the north around 100 miles to a location on the Ross Sea, adjacent to the Mackay Glacier which flows out of the Central Transantarctic Mountains. The field party had already been at work for 3 weeks – and I was flying in for the final push. As we flew out, Thai sat near the window and surveyed the ice beneath us. Our camp was set up on sea ice, and the traverse back to McMurdo was going to involve driving 100 miles across sea ice which, at this time of year, is starting to show significant cracks.

From the window of the helicopter I marveled at the icebergs which had calved off from glaciers and became frozen into the sea ice when it froze for the year last year. It was like watching time stand still before my very eyes. Some of the icebergs stand 200 feet tall or taller (and considerably deeper than that below the water surface) – and they reflect light in the most amazing ways, with every shade of white and blue and gray. They stand like sentinels with ever-changing light.

As we flew, we left the volcanic province that surrounds the McMurdo area, and flew past the Dry Valleys and along the Central Transantarctic Mountains. By the time we started to land, we were in an area with high granite cliffs surrounded by expansive glaciers coming right down to the vast frozen Ross Sea. Many of the mountains were covered with ice, but mountain peaks could be seen deep into distance.

As we approached camp we could see flashes of blue and yellow on the frozen seascape below. Towering pinkish granite cliffs came right down to the ice. We gently landed right next to camp, and, when given the signal, I took off my helmet and climbed out of the helicopter. I had arrived!

My friends, who had gone out three weeks earlier, welcomed me warmly and showed me around camp. I was struck by how cozy and warm camp was – out in the middle of the Antarctic wilderness. There were 2 Rac tents, one for cooking/eating/socializing, and one for computing/data processing/ storing and drying out field gear. Scott tents were used for sleeping, 2 per tent, with one bathroom tent.

I couldn’t get over the views from camp. For the first hour, I couldn’t bring myself to go “inside.” Rather, I just walked around and around thinking, “I must be the luckiest person in the world!” Then, when Joan, our cook, made a beautiful dinner of beef in a coconut curry sauce, I knew that I had indeed found Nirvana!

A typical day was to wake up between 6:30 and 7:00 am, and eat a hearty breakfast of pancakes and bacon, or eggs and potatoes, and coffee. By 8:00 we were on our way to the field. (See my previous blog to learn about the purpose for the survey and the way it was conducted). Before the seismic surveys were done, a line had to be flagged. For the first couple of days I was involved with flagging the lines. This entailed using a GPS unit to establish a location. A 50 meter cable was then used to plant a flag every 50 meters, keeping a perfectly straight line with the previous flags. When the flag location was determined, an auger was used to drill a hole in the ice to securely plant the flag. The lines were typically 1 or 2 kilometers long. Once the line was established, we had to go back and label all of the flags, and get an accurate GPS location for each flag, as these would soon be linked to the geophysical data being collected.

The driller and the science lab, both pulled by Piston Bullys, followed later. They would pull their equipment up to each flag and drill, and then collect seismic data. I worked both with the driller, shoveling snow away from the drill hole, and with the science lab, deploying the airgun into the hole. At the appropriate moments, the seismologists would fire the airgun, and their computers would monitor the return of the sound waves from the sea floor and below to the geophones which were in a streamer behind the mobile science lab.

My first day in the field, we were concentrating on flagging a line, when suddenly we saw three emperor penguins walk up to us! They are so playful and curious – and walked right up to us, with absolutely no fear. They stood near us for at least 15 minutes while they interacted with one another, squawking and rubbing beaks, and finally the scooted off. Little did they know they had absolutely made my day!

One day, after our work was done, we went exploring a nearby point called Cape Archer.
To get to Cape Archer we drove our snowmobiles past some deep pressure ridges with seals all around. Here we were able to get up fairly close to see the mother seals and their young pups. The mothers noticed when we approached, but were not afraid. Nearby, there was a seal hole where a mother and her pup kept bobbing up and down in and out of the water. I felt so privileged to have this close encounter with Weddell Seals – and for them to not be frightened of me! I knew I was a visitor in their territory and I felt humbled by their acceptance of me.

A bit beyond, we came across a magnificent ice cave at the edge of the interface between a granite cliff and a glacier. The colors, texture, and lighting were beautiful as we treaded into the cave – through an old crevasse which used to be deep in the heart of the glacier before it advanced its way toward the sea.
One was always aware that bit could break off or shift at any time – so we didn’t venture too far in, but it was spectacular nonetheless.

After just 9 days in the field, our work was done and it was time to head back to McMurdo with all of our gear. We were going to traverse back from Granite Harbor to McMurdo. The traverse was one of those profound events in life that are
difficult at the time, but that you wouldn't miss for anything. I rode on the back of a snowmobile for 13 hours. The traverse party consisted of 2 snowmobiles, each with 2 persons, and two Pisten Bullys pulling laden-down sleds full of gear, and a total of 6 passengers.
We left sunny Granite Harbor, and in less than a half hour, we were in overcast skies and moderate visibility. The ride on the snowmobile was cold and windy, but a great adventure.
We rode past icebergs, nursing seals, big cracks in the sea ice. We plodded along slowly, with the Pisten Bullys being our limiting factor (maximum speed of perhaps 15 mph). But slowly the mountains and glaciers moved behind us, and Mount
Erebus come closer into view. The snowmobiles stopped at the ANDRILL drill site for a brief bit of warmth and a tour, while the Pisten Bullys went on ahead. 45 minutes later, we took off from the drillsite and sped on to catch up with the advance party of Pisten Bullys. Partway there, 3 Adelie penguins came waddling across our path. With due humility, we silenced the engines and squatted low for them to come and check us out. They appear to be such happy creatures! Again, there were fearless and inquisitive!

When they were done checking us out, and slid off on their bellies, we ignited our engines and took off for the final stretch – to catch up with the Pisten Bullys and make it home in time for "midrats" (Midnight Rations – the midnight
meal served in McMurdo). A windstorm picked up on our final stretch, and our last leg was though a blizzard. We followed the flags to circumnavigate the ice runway, and finally reached McMurdo just before midnight.

Room keys were awaiting us at the housing office. We charged for the showers – and welcomed the chance to get clean – and then settled in for a hot meal and some much needed sleep.

I would have happily stayed out for another two weeks – but I am thrilled to have had the opportunity to get out into the deep field.

Meanwhile, back in the ANDRILL lab, we hit our target depth of 1,000 meters and the windows into climates past are continuing to captivate the science teams. After a brief pause to do some logging of the drill hole, we will continue drilling for another few days before calling it done. The ice is started to soften a bit, and they will need to haul the whole rig (90 tons of it!) soon. What a sight that will be!!

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