Homework #2 Humphrey Geology
4888/5888 Fall 2008 GLACIOLOGY
Notes:
This should take you 1-2 hours.
Your work must
be neat, legible, and organized. I am not
willing to wade through a mess and I will just give it back to you to
re-do. You can work with others, but be
aware that you will have to do similar questions on exams and quizzes, by
yourself.
You should be working through
the first 5 chapters of
1 (A question to find out if you
followed the class demo on super-cooled water.)
Assume the water was super-cooled to -5C. What was the percentage of ice in the bottle,
after freezing? (note you do not need the original
amount of water)
2 (And another question to see
if you followed the discussion on stress in a slab type glacier). Consider a long
valley glacier. The central region is
wide and straight. The slope is 3
degrees.
a) Use the ‘1 bar basal
shear stress’ approximation to find the glacier depth.
b) Plot on one graph: 1- shear
stress vs depth, 2- the z component of the normal
stress, 3- the z component of the deviatoric stress,
and 4- the effective stress. In this
question you can assume that there are no longitudinal stresses (no deviatoric stresses in the x direction), and that any cross
glacier stresses are negligible (no stresses in the y direction).
Please come and ask me if you
don’t understand a question. I
realize that the questions may make a lot of sense to me, but not to you!