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11 December, 2002
Drilling Extravaganza
Date: 12/11/02=09
Latitude: 82=B0 00=92 03.59=94 S
Longitude: 110=B0 00=92 29.59=94 W
Time of Observations: 10 PM local time
Temperature: -16 C/ 3 F
Wind speed: 6 knots
Wind Chill: -23 C/ -9 F
Wind direction: Northerly
Meters of ice collected: 142m=09
By Susan Kaspari
As Betsy put it, we were busy as a beehive in the middle of nowhere
today. It was an overcast day, but the winds died down and made
working outside a pleasure. Betsy did three successful ozone
measuring balloon launches (the beanie babies went along for one of
the launches). Markus drilled ice cores for the continuous melter and
worked on a firn air vs. snow air ozone concentration experiment.
Gordon and Blue did a survey at their mass balance site and started
drilling the Beta ice cores with the drill. Paul, Mark, Dan and Susan
drilled ice cores with the drill. Brian worked on his radar
antennas, and Jim was the man around town helping Brian and Betsy out
and double-checking the radar data. Lynn and Carl welded brackets for
a tailgate for the Berco sled, loaded empty fuel barrels on the sleds
and organized cargo. Andrea was again successful at fattening us up
and keeping us happy. We had a yummy BBQ dinner with fresh potato
salad.
The name of the game in camp today was ice core drilling. US ITASE
uses two drills, the diameter drill, and the diameter Eclipse drill
that is our primary drill. The Eclipse drill was designed by Icefield
Instruments of Whitehorse, Yukon Territory and has been used in=20
Antarctica, on Mt. Everest, in the Tien Shan range in Asia, and on
Mt. Logan in the Yukon. The Eclipse drill that we use was specially
built and purchased for US ITASE. The advantage of the Eclipse drill
is that it is lightweight (800 lbs), can be broken down into 50-60
lbs. bundles, can be assembled in the field, is mounted on a sled,
and is a dry drill. Dry drilling has no impact on the environment. In
comparison, wet drills go to deeper depths but require fluid that is
the same density of ice to keep the drill hole from closing up. The
Eclipse drill is an electromechanical drill made of aluminum and
stainless steel that can be powered by solar panels or gasoline. The
winch on the drill requires 3000 watts of power when raising the
core, so we use a gasoline powered generator to run the drill.
The drill has an inner and an outer core barrel. The inner barrel has
cutters on the end of it, and as the drill is lowered into the ice
the inner barrel spins and cuts the ice. The outer barrel has
anti-torque strips at the top of the drill to prevent it from
spinning while in the hole. We drill ~1m long pieces of ice. When the
drill is lifted the=20 core dogs, which are small cutters with
springs attached, grab into the ice, break it, and prevent the ~1
meter long ice core from falling out of the barrel as it is lifted
back up out of the hole. Ice chips from drilling the ice core are
pulled up with the ice core in the top of the core barrel. Operation
of the Eclipse drill requires a professional driller. Mark knows the
drill inside out and does an amazing job keeping the drill running
smoothly. After a piece of ice is drilled, the whole drill is lifted
out of the hole with the winch, and the core barrel tilts
horizontally so the ice core can be extracted. Susan measures the
length, diameter and any breaks on the ice core and Dan weighs and
packages it for shipment back to the United States. One meter of ice
weighs about 4 kg. This adds up to be a lot of weight to haul around
in the field. The drill, designed by Mark, is similar to the Eclipse
drill except that it is smaller, lighter - only 200 lbs and is
powered by solar panels and a hand winch. We have to dig a 1m pit to
lower the Eclipse drill into the ice, whereas the drill can begin
drilling at the ice surface, which means we don't have to dig snow
pits. The Eclipse drill is better designed for drilling at deeper
depths (it has a 200 m cable) and provides a larger core so that more
analyses can be done. The 2 drill's advantages are that it is
lightweight, highly maneuverable, and can be operated without a
professional driller.
It's great to finally be on the road and doing our research. We'll
wrap up our research at site 1 tomorrow, pack up, and the road
trip=20 will continue on to scenic site 2.
Contact the TEA in the field at
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