Winter operations, 1970-1971 / John C. Ayers, Norbert W. O'Hara, William L. Yocum.

5. The Developed Ice Rampart
Continued wave activity builds ice cones around the mouths of the blowholes. This condition may be considered a "mature" stage of the ice ridge, for
its high lakeward face favors undercutting and collapse. Figure 7(22) presents
this stage of the ice rampart.
6. The Collapsed Rampart
Wave undercutting, cracking, collapsing of blocks of the rampart, and the
melting action of sunlight warming the sand incorporated into the ice all act
as destructive forces to lower and compact this rampart. These conditions are
illustrated in Figure 8(24). Figure 9(25) shows the melting effect produced
when the sun warms sand incorporated in the ice.
The above stages appear to be the sequence of events that lead to the establishment of a first ridge of ice immediately along the shoreline. This is
the first ridge of the icefoot and for discussion purposes is designated Ridge A.
As the result of increasing wavr action from north to south in the Cook
Plant area, most of the above stages were present in a progressive sequence from
north to south on 29 Decembl- 1970.
7. The Formation -r Ridge B, The Second Ridge of the Icefoot
Ridge A may wa'- and wane after its initial formation, as the accretive
forces of new,corms, delivering ridge materials, overmatch or undermatch the
destructive forces of undercutting, breaking off, collapsing, and melting.
Eventually, however, there arrives a push of floe ice ("brash" in Marshall's
terLinology) which piles up, reaches to bottom, and freezes into a second ice
ridge close against and just lakeward of Ridge A. The presence of Ridge B shuts
off wave action from Ridge A, and further accretion to this ridge is stopped.
The destructive forces, however, continue to operate and Ridge A becomes progressively lower, more compact, and more sandy as can be seen in later figures.

6