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Salient. An Organ of Student Opinion at Victoria University, Wellington N.Z. Vol. 22, No. 5. June 8, 1959

Some Go West But ... — Victoria Goes South

page 4

Some Go West But ...

Victoria Goes South

Last summer a four-man party from Victoria University made some contribution to the knowledge of a small area of Antarctica by treating it unconventionally.

Nowadays the emphasis in polar exploration is swinging more and more to the large expedition, equipped with modern mechanical transport, and usually with considerable indebtedness to the taxpayer of the sponsoring country. Particularly is this true of the Antarctic, but the same applies to the Arctic as well.

However, in the northern regions a valuable amount of exploration, mapping, geological surveys, glaciological and meteorological investigations and so on—have been carried out, over the years, by small, modestly - equipped parties from the universities of Great Britain.

Because of the difference in scale of the transport problem at the two ends of the world, University expeditions of this kind to the Antarctic have not been feasible, but in this last summer, by using transport facilities generously offered by the United States authorities, it proved possible to mount one.

Valleys Ideal

The Wright Valley and Victoria Valley area of South Victoria Land was ideal for us. It is most unusual, being practically free of ice—and this allowed us to plan a back-packing expedition.

It is close enough to the U.S. Naval Air Facility at McMurdo Sound—about 80 miles away—to make the support of the expedition by the Americans not too onerous a task. It is a small enough area—2500 square miles—to allow us, in a short season, to investigate a reasonable part of it. And most important, it had only been visited once before, by a four-man party who spent 10 days in the Victoria Valley in February, 1958.

Fascinating

This fascinating deglaciated area lies to the west of McMurdo Sound in the mountains of Victoria Land. It is separated from McMurdo Sound by the Wilson Piedmont Glacier, which is about 12 miles broad and rises to 1500 feet above sea level.

In the south the area is bounded by the Taylor and Ferrar glaciers, in the west by the inland ice, at an altitude of about 8000 feet, and in the north by the Miller and Debenham Glaciers. The region consists of continental rocks, whose maximum altitude increases from 5000 feet near the coast to 8000 feet near the inland ice plateau.

It is transected by two major east-west valley systems, the Wright Valley in the south and the Victoria Valley further north. Both valleys are more than 40 miles long.

The Wright Valley averages about five miles in width, and for most of its length the floor is at least 1000 feet above sea level. The Victoria Valley is more complex, splitting into three distinct arms in the western half. It is wider and lies between 1000 and 2000 feet above sea level.

During the early years of this century parties from Scott's and Shackelton's expeditions penetrated the entire length of the Ferrar and Taylor Glaciers, examined the Wilson Piedmont Glacier and the Taylor Dry Valley, the deglaciated coastal end of the valley once filled by a more extensive Taylor Glacier.

This article on Victoria's Antarctic research has been specially written for Salient by members of the party.

However, it was not until reconnaissance flights bad been made in 1956 and 1957 by aircraft of the U.S. Navy and the New Zealand part of the Trans-Antarctic Expedition that the full extent of the ice-free area to the north was appreciated.

Since ours was the first expedition of this kind to the Antarctic we made it a small one. Three of the members, Dick Barwick, the zoologist, and Peter Webb and Barrie McKelvey, both geologists, had spent one or more summers in the Antarctic, while the fourth Colin Bull, geophysicist, had spent two years in the Arctic.

Base Camp

We were taken down to McMurdo Sound in a U.S. Navy Super Constellation and from there to the Wright Valley on December 12 by U.S. Navy Helicopter. A base camp of two pyramid tents and seven weeks' food was established at the eastern end of Lake Vanda, the five-mile long, ice-covered lake which occupies the lowest part of the valley, 30 miles from the coast, and we made also small depots of food and fuel at the eastern and western ends of the valley.

South Arm, Wright Valley, showing Dais mosa on the left (3000ft.) with the 5000ft, high sides of the main valley in the distant background.

South Arm, Wright Valley, showing Dais mosa on the left (3000ft.) with the 5000ft, high sides of the main valley in the distant background.

Member V.U.W.A.E. expedition 1958-59. Left to Right: Dick Barwick, Colin Bull, Peter Webb, Barrie McKelvey.

Member V.U.W.A.E. expedition 1958-59. Left to Right: Dick Barwick, Colin Bull, Peter Webb, Barrie McKelvey.

The Wright Valley, being long and narrow, and having side walls 5000 feet high, completely controls the local winds—either they blow up valley, or down valley.

We worked in pairs; Peter and Barrie together carried out the glaciological work, while Dick and Colin divided their time between survey, geophysics and biology.

The two pairs worked separately from one another, but, for safety's sake we carried two small battery-operated radio sets and had daily contact with each other, and with Scott Base twice weekly. Using the three scattered food depots we managed to cover adequately the southern half of the dry-valley block and part of the north.

Anomalous

Fascinating is certainly the right word to use for the area. Many aspects seemed anomalous. To start with, the weather was surprising.

At our base camp, which was about 500 feet above sea level the temperature rose on two days to 47 degrees F, while the lowest was only 22 degrees F, and the average for the 52 days that we were there was 33 degrees F.

This is about 15 degrees F higher than the average temperature for December and January at Scott Base, and about 10 degrees F higher than the value for the U.S. station at Marble Point on the coast of McMurdo Sound, 40 miles east of our base camp.

Hot and Cold

The winds blowing from the inland ice were warm; those from the sea were cold, and the switch from the easterly to westerly winds of moderate strength was often very rapid, and was accompanied by an equally rapid change in the humidity. The winds from the plateau were much drier than those from the sea.

We should have avoided writing "up valley and down valley" for the following reason. At the coast-ward end of the Wright Valley the altitude of the valley floor is 1000 feet. In December and January the melt-water from the Wilson Piedmont Glacier forms a considerable river which flows inland for a distance of 25 miles (Is this the longest river in Antarctica?) until it flows Into Lake Vanda, whose altitude is 400 feet.

Further west the valley floor rises slowly over a distance of 10 miles to about 2000 feet, and then more rapidly, over the next six miles, to 7000 feet. No water flows out of Lake Vanda and at present its level seems to remain almost constant, so that the water loss by evaporation must balance the inflow, but in the recent past the lake level has been much higher.

During our seven weeks in the field the two geologists covered about 600 miles on their traverses. We now have a reasonably good idea of the geology of the area.

Naturally, the investigations have not been detailed, but we mapped most of the area well enough so that the specialists, with their particular problems, know what to expect here. The extent of the pre-Cambrian metamorphic basement, and of the younger Beacon sandstones, has been mapped, and the relation of these to the intruded granites and dolerites has been investigated.

Over the last few years many measurements of gravity have been made in the McMurdo Sound area, and a few on the inland ice west of Victoria Land. Such measurements allow one to learn about the stability of the area, page 5 whether or not the land is rising due to the slow removal of the load of ice.

Since the Wright Valley offers an easy route, Bull and Barwick made a 50-mile gravity traverse from McMurdo Sound, over the Wilson Piedmont Glacier and along the valley to within six miles of the plateau. We could not go further in our limited time.

The main results have not been worked out yet, but we did use the gravity readings to determine the ice on the Wilson Piedmont Glacier and the depth of water on Lake Vanda.

Along our route the greatest thickness of ice was about 1200 feet, and since the altitude of the top of the glacier was 1400 feet, the bottom here is very little above sea-level. The greatest depth of water in Lake Vanda is about 250 feet.

Seals Inland

The most surprising biological findings were many seal carcases along the valley floor, from the coast to 45 miles inland. Seals have been found inland in Antarctica before, but never in such large numbers.

We found 99. Some were quite recent, and still soft enough to allow post-mortem dissection; others were very old, so that they had been dehydrated and then eroded by wind and sand until only a few bones remained. Lots of interesting problems are posed.

How old the seals are we hope to find out from radio-carbon dating of the specimens we brought back. Why do they migrate inland? We do know that they eat on the journey—nothing except sand and gravel—but we don't know how long they take.

Because so much of Dick Barwick's time was taken up in helping with the survey work—we took rounds of angles from 10 points in the dry-valley block and on the coast—he could not devote as much attention to the freshwater biology as it deserved.

But we did collect lichens during these survey journeys, noting, yet another apparent anomaly, that they were confined to areas above about 3500 feet in altitude, and we spent a few days collecting specimens from the small lakes near the base camp.

Reluctant

When the helicopter came at the end of January to take us back to Scott Base we were reluctant to leave. Our seven weeks had been very enjoyable and most rewarding, but in that time we had not been able to do full justice to the scientific potentialities of the dry-valley block.

Other Universitiy parties will, we hope carry on with the work. Ours was a "try-out" expedition and we are pleased that we were able to justfiy the confidence placed in us by the New Zealand and U.S. authorities, by the University, and by the many New Zealand firms who supported us.