8 July, 2000
July 8, 2000
Today was a slow day. We finished drilling at this site yesterday, and
gathered borehole video data. All three boreholes have been instrumented
with pressure transducers that will monitor the rise and fall of water in the
holes. We hiked out to look for our next drilling location - about half a
kilometer further away from Hidden Creek Lake. A helicopter will arrive on
the 10th (Monday) to lift our camping and drilling equipment out to the new
location.
The cracking sounds that continue near our camp are beginning to manifest
themselves as surface fractures in thee ice. A crack began opening near our
second and third borehole a day ago. It is now a couple of inches wide and
is extending as a series of left-stepping fractures toward our camp. These
series of cracks was also headed straight for the tent of PI Andrew Fountain.
He picked up and moved his tent well away from this growing feature. These
fractures are developing as a result of the ice dam being lifted and
cantilevered by the rising water of the lake. They show both lateral and
vertical displacement. They are interesting because they are the result of a
primary compression force and not the tension forces that typically lead to
crevasse opening. A few days ago the cracking sounds were a bit unnerving.
I seem to have gotten used to them.
After inspecting the operation of the hot water drill (which he designed and
built), and spending a couple of days with us, University of Wyoming
glaciologist Neil Humphrey and his friend Sue Child left our camp this
morning. What I will remember about Neil is that he can fix anything, and
further, fixing stuff is his passion. He especially likes the challenge when
the appropriate spare part is not available. He spent a bunch of time
talking on the radio with PI Joe Walder at the lake yesterday. Joe was
having problems with some of his transducers and data loggers. Whatever Neil
suggested to change seems to have helped. The borehole camera was damaged in
a manner that I thought was irreparable. Neil did not fix it, but he
improvised some spare parts out of O-rings and grease and returned it to an
operable condition so that it can be used for the rest of the project. His
friend Sue broke the frames of her glasses. He fixed them. The only thing
that he could not fix, try as he might, was our mechanical butane fire
starter that we use to light our stove.
Surveyor Dennis Trabant (U.S. Geological Survey, Fairbanks) is on the bluff
overlooking the lake and ice dam. Every four hours he surveys the position
of the 30 reflectors he put on the ice dam. He is also using his surveying
equipment to monitor the surface of the lake. It is still rising - it rose 2
feet today.
A crevasse began opening near our camp a couple of days ago. It is now 4 inches wide, and continues to expand slowly. This crevasse is also in line with the former tent site of PI Andrew Fountain - he could hear it cracking and popping under his tent at night. He moved his tent to a different location today.
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