GEOLOGY: W. E. EKBLAW 
289 
nivation and solifluction attain a degree of importance in northern Greenland 
not generally appreciated. 
Nivation is the process by which quiescent neve effects the disintegration 
of rocks, and the destruction of some land forms, and the formation of others. 
In this process the snow itself produces very little, if any, effect; it is the 
water from the gradual melting of the snow that does the work. The melting 
must be so slow and gradual that the water does not escape by surface run- 
off, but soaks into the layer of rock fragments or soil above the ice-table, and 
then seeps slowly downward and outward from its source. 
Nivation is assuredly most effective in regions of pronounced relief, and 
strong and variable winds, conditions prevalent in Greenland. Under such 
conditions, the snow does not lie as a mantle of uniform thickness, but is 
piled up in drifts of various kinds. For the sake of clearness, I have classi- 
fied these drifts into two, or three, rather distinct divisions, more or less 
characteristic of the kinds of localities in which they are found. These divi- 
sions are (1) dome-shaped drifts, formed on the more or less uneven tops of 
plateaus, on the small plain areas, and on other relatively level surfaces; 
(2) piedmont drifts, formed along the foot of extended cliffs, or series of cliffs; 
and (3) wedge drifts, formed in gullies and small gorges near the top of cliffs. 
The dome-shaped drifts vary in size with the size of the plateau or plain 
surface upon which they lie, and with the strength and character of the winds 
that blow over. On the small segments of a plateau surface dissected by 
gullies or stream beds, these dome-shaped drifts may not be very large or 
very thick; on larger segments, they may form one large dome, or several, 
all, or some, very thick, — in cases even becoming small ice-caps. Thus there 
may be every gradation from small dome-shaped drift to the great ice-cap of 
Greenland. If the winds that blow over vary considerably and rather uni- 
formly in direction, the domes are somewhat symmetrical; if not, they slope 
gradually toward the windward side, and quite abruptly on the other. On 
the plateaus north of Foulke Fjord, the winds blow from almost all points of 
the compass, as often, almost, from one direction as another, and the drift 
slopes almost uniformly from the center to the whole peripheral edge; on 
Herbert Island, where the winds blow generally from the South, the dome 
slopes gently in that direction, while on the north side, the slope is abruptly 
precipitous. Very few of the tops of the plateaus are free from dome-shaped 
drifts; and many terraced moraines, deltas, and plains are covered by the 
same form. 
The piedmont drifts are those that form along the cliffs on the windward 
sides of valleys, fjords, and straits, on the lee sides of capes, peninsulas, and 
islands. They are formed from the snow that comes drifting over the lands 
back of the cliffs, and piles up on the talus slopes below, at the foot of the 
cliffs. Thus, both sides of Foulke Fjord are bordered for almost nine months 
of the year by these piedmont drifts, those on the north side from the snow 
carried over by northerly winds, those on the south from the snow carried 
