Daily reports from the NGRIP-camp - week 30 year 2000
Monday, July 24th
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| Daily life |
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| Science |
| The drill is still stuck, and we do not know why. In the morning 160
liters of glycol was dumped into the drill hole. Glycol melts ice and is
heavier than the drill liquid in the hole, so the glycol will sink to the
bottom and melt any possible ice around the drill. To avoid closure of
the deeper part of the hole as much as possible heavy drill liquid was
dumped into the hole. Since the upper part of the hole is surrounded by
porous firn the highest possible liquid level in the hole is 64 m depth.
An attempt was made to separate the drill's motor section from the stuck
part of the drill by reverse rotation of the drill, but unfortunately the
operation was unsuccessful. The temperature sensors in the drill indicate
that the drill liquid is -5 C at the bottom of the hole. The drill was
left overnight with a cable tension of more than 10000 N. |
| Logistics |
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Tuesday, July 25th
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| Daily life |
| Despite the sad circumstances a muskox BBQ is prepared for dinner.
The meat is however tough as leather! |
| Science |
| The drill situation is unchanged. A calculation shows that the pressure
in the drill liquid at the bottom of the borehole is larger than the pressure
of the surrounding ice. The hole will therefore slowly expand. The science
team processes the last ice core that was drilled, then the science trench
is closed for the winter. Even if the drill would get loose this year it's
too late in the season for processing any more core this year. |
| Logistics |
| Preparations are made for tomorrow's flight. |
Wednesday, July 26th
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| Daily life |
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| Science |
| The drill is still stuck. Experiments are made to freeze glycol. Monday
liquid glycol was dumped in the hole in order to melt possible ice at the
drill. The problem is if the glycol sinks all the way down to the bottom,
or if it melts ice or chips on the way down the hole. Therefore one will
try to freeze the glycol at the surface and let it sink to the bottom in
solid form. At the bottom the temperature is higher and the glycol will
melt. Then it will melt ice. |
| Logistics |
| The first weatherport tents are taken down. The closing down of the
camp has started. A Hercules skier arrives with four new participants.
18 persons are flown out, so that now a total of 13 persons are left in
camp. The work on trying to loosen the drill will continue, but even if
the drill loosens this year, it is most likely too late to continue drilling
this year, so there is no need for many people in camp. |
Thursday, July 27th
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| Daily life |
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| Science |
| The drill is still stuck. Today glycol was frozen successfully in the
drill trench by use of a freezer. At 9 pm 3.5 liters of frozen glycol cut
into cubes were dumped into the bore hole. Around midnight another 6 liters
followed. According to calculations it should take the glycol 2-4 hours
to sink the 3 km to the bottom… |
| Logistics |
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Friday, July 28th
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| Daily life |
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| Science |
| The drill is free again! After the frozen glycol was dumped into the
hole the temperature of the drill started to decrease. This indicates that
the glycol is active and melts ice at the drill. At 5 am, when a total
of 7.5 liters of glycol was dumped into the hole the temperature at the
drill had dropped from -6 to -9 deg. C. Then the tension in the cable decreased
and the drill started to move upwards! At 7:07 am the drill was back on
surface. The drill has not been damaged seriously. The reason why the drill
got stuck is probably packing of ice at the drill head. This packing did
most likely occur because the drilling has reached 'warm' ice - ice that
is heated from bedrock. This ice has other properties than the colder ice
which has been drilled until now. |
| Logistics |
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Saturday, July 29th
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| Daily life |
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| Science |
| After the drill became loose the bore hole has to be cleaned for the
about 160 liters of liquid glycol that were dumped in the hole Monday morning.
This glycol, which is now located in the lower 100 m of the hole, melts
the sides of the bore hole and makes trouble for the drill electronics.
Therefore a bailer is mounted on the drill and the drillers start to empty
the lower 100 m of the hole for glycol and drill liquid. |
| Logistics |
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Sunday, July 30th
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| Daily life |
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| Science |
| The cleaning of the hole is continued. When the bailer comes to surface
full of glycol it is difficult to clean, so a 'heat box' is constructed
with a Herman Nielsen heat blower, which can unfreeze the tank and its
content. At the end of the day the surface of the glycol is about 88 m
above the bottom of the hole. The cleaning continues in shifts 24 hours
a day. |
| Logistics |
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Read more about Week 31
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