Geology Reference
In-Depth Information
Figure 1.8.
Marvin (left) and Crozaz (right) in the C-141 Starlifter en route from Christchurch to McMurdo.
develop most readily on ice that has no outlet but loses
volume due to ablation of its exposed surface.
1.14.2. The North Victoria Land Camp
In 1978-1979, the NSF had built a season-long field
camp, similar to the Darwin Camp, to serve several pro-
jects in North Victoria Land (NVL), 600 km north of
McMurdo Station. John Schutt and Bob Fudali arrived
at the NVL Camp on 24 November to carry out recon-
naissance of ice patches that were visible on air photos.
They also planned to visit a small circular feature at Littel
Rocks to determine whether it could be an impact crater.
They made numerous helo flights over ice patches that
were strewn with rocks, but frequent stops revealed that
the rocks were terrestrial, with no noticeable meteorites
among them. When they left the area, they reported that
they could not declare there were
no
meteorites in the
rocky debris at NVL, but using their best efforts they did
not find any.
The crater at Littel Rocks proved to be a former lake
that had been overridden by ice more than once. They
found no sign of impact features associated with it. So
Schutt and Fudali returned to McMurdo.
Figure 1.9.
Measuring the 5-cm ablation of ice at a flagpole of
the geodetic net.
a short distance westward. However, a succession of
storms that barely allowed them to complete their mea-
surements prevented them from making an addition at
that time. They left the field on 13 December.
Schultz and Annexstad reported the following results:
the ablation rate of the ice at the Allan Hills Main Icefield
averages about 5 cm per year (Figure 1.9). This serves
well to expose new meteorites that have been frozen
within the ice. Their measurements of horizontal ice dis-
placement since 1978 indicated that ice moves rather rap-
idly eastward from the western plateau toward the Allan
Hills, but it slows down and becomes stagnant at the foot
of a steep slope that leads to a narrow flat-bottomed
valley about 4 km wide. On its icy surface, it holds the
meteorite concentration. Concentrations like this one
1.14.3. A Visit to Granite House
Before the season began, I had persuaded Bill Cassidy
by telephone to request a helicopter flight to Granite
House, a historic edifice that was built in 1911 by four
members of Scott's expedition, led by Griffith Taylor, who
were mapping the coast of Victoria Land. When they
exhausted their kerosene, they fashioned this structure out
