16

First-Year Ice

Multiyear Ice

S B = 14.237 0.194TF

12

8

S B = 7.879 0.016TF

4

0

100

200

300

400

TF, Floe Thickness (cm)

kov 5/4

4

3

2

σ C (T-F) = 0.621 + 0.855 σC (Ex)

1

r 2 = 0.942

0

1

2

3

4

σC ( Ex) , Exxon's Horizontal Unconfined Compressive Strength (MPa)

reveals the interrelationship of average ice sheet

and Frederking. However, the modified method

for determining σc gives values that are still offset

temperature and bulk salinity with the bulk po-

rosity.

from the Exxon field test results (Fig. 15). To alle-

Using the *S*B values determined from eq 2, the

viate this offset, eq 5 was revised to read

average ice floe temperature listed in Table 3, and

the equation provided in Figure 13, φB was esti-

(

)

σc = 37 ε0.22 1 - φ B.93/ 270

0.5

0

- 0.65 .

˙

(8)

mated for each of the Exxon ice sheets. These νB,

This revision brings the σc values (Table 3) into

column under each respective heading. Using the

new φB values and the related strain rates in Table

better agreement with the field determinations,

3, σc was recalculated using eq 5. These so-called

as shown in Figure 16.

modified σc values were then compared (Fig. 14)

with the σ c estimates made by Timco and

termined remotely along with ice sheet thickness,

then *S*B could be determined from eq 2 and νB

Frederking (Table 3). As can be seen in Figure 14,

using the above φB estimates in eq 5 gives σc

estimated from an expression similar to that given

in Figure 6 and φB from Figure 17. The data in

values that are comparable with those of Timco

8