Whitesail Lake Map-Area

accumulated first on the crest of the Coast Mountains. When the accumula-
tion reached sufficient proportions the ice flowed off these northwesterly
trending mountains in an initial northeasterly direction. Any easterly or
northeasterly trending valley would naturally provide an excellent channel
for ice movement. As the process continued the ice grew thicker, filled the
valleys, and finally flowed over the top. To do so the ice must have reached
a thickness of around 4,500 feet finally moving as far east as the Nechako
Plain (Armstrong, 1949, p. 8) and merging with ice from other gathering
grounds. It would appear that this ice advance was alpine and piedmont
glaciation on a grand scale.