143-156 - International Glaciological Society

JO URNAL OF GLACIOLOGY
In our case, h = 0.12 m and wh = 1.4. Finally,
u = [U+ Uaw2z exp (-wz) cos wx] + Uaw(0.727 cosh wz-o.716wz sinh wz) cos wX }
W = [- Uaw( 1+ wz) exp ( - wz) sin wx] + Uaw( 1.443 sinh wz-o. 716wz cosh wz) sin wx,
the terms in square brackets are the solution for h = 00. With a uniform velocity at a finite distance the modification
is not negligible, in particular, against the "bedrock" the forward velocity u increases over the bump. The
normal stress at is calculated as
aUt ( a'u a2U)
Tz = -1/ 3 aX2 + aZ2 .
(A-3)
It yields
at = [-Pi + 2TJUaw2( 1+ wz) exp (- wz) sin wx] +
+ 2TJUaw'(1.443 cosh wz-o.716wz sinh wz) sin wz,
o 0
au dx
·
[ 8
] ·
= az U = -0.471 aw Sin wz ->/, = -0.080,
-T/2 -AI.
J au d
t
az I
o
aw
J
[WJ"
ax dt = 7J -,,,
- Tt2
= [ -0.378 65aw sin wx]w = -0.054.
REFERENCES
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