The profiles of the crystal grains, as presented in figures 11 and 12, show the 

 relation between the size of the crystal grain and the size distribution per unit 

 area. For nearly all depths in the ice sheet, the highest percentage of crystal grain 

 size lies in the 0.5 mm to 1.0 mm region. 



Other Physical Properties 



CONDUCTED HEAT FLOW THROUGH AN ICE SHEET 

 WITH A SNOW COVER 



Figure 15 shows the conducted heat flow per unit area from the water through 

 the ice sheet, the snow cover, and into the atmosphere. The data cover a period 

 of one week from 27 March to 2 April 1955. Resistance-wire thermometers and 

 Western Electric type 14B thermistors served as the thermal elements and meas- 

 urements were made with a Leeds and Northrup type S bridge. Malmgren's^* 

 values for the thermal conductivity of ice are used in the calculations. The thermal 

 conductivity value for snow is the average value found in Dorsey.^^ The measure- 

 ments represent a preliminary heat-transfer study,, in which the convective heat 

 flux, the evaporative heat flux, and the heat of ice formation have not been 

 measured. 



RESISTIVITY MEASUREMENTS IN SEA ICE 



The apparent resistivity measurements in sea ice represent a preliminary survey 

 of techniques and necessary instrumentation. The apparent resistivities (table 5) 

 show a wide variation with increase in electrode spacing. The ice thickness in the 

 area of these measurements showed an average value of 84.0 cm (33 inches). The 



TABLE 5. Apparent dc resistivity measurements. 



Separation of 









Electrodes 



Potential 



Current 



Resistivity 



a 



E 



(mv) 



/ 



(ma) 



191 a{EID 



(feet) 



(cm) 



(ohm-cm) 



0.25 



7.62 



1150 



78 



705 



0.50 



15.24 



820 



70 



1120 



0.50 



15.24 



725 



58 



1187 



0.75 



22.86 



500 



48 



1490 



1.0 



30.48 



300 



40 



1432 



1.0 



30.48 



575 



82 



1340 



1.5 



45.72 



180 



34 



1517 



1.5 



45.72 



330 



63 



1500 



2.0 



60.96 



325 



80 



1550 



2.0 



60.96 



300 



88 



1300 



3.0 



91.44 



100 



64 



895 



3.0 



91.44 



125 



70 



1023 



4.0 



121.92 



70 



69 



773 



4.0 



121.92 



30 



75 



305 



6.0 



182.88 



15 



90 



191 



6.0 



182.88 



10 



102 



112 



21 



