13 
that covered the whole region (8, 32) . It is thought that the present main 
drainage lines, such as those of Athabaska, Peace, and Slave rivers, have 
maintained themselves with modifications from late Cretaceous or early 
Tertiary time, and have persisted through the Pleistocene. The Cretaceous 
plateaux of Birch and Caribou mountains have, according to Cameron (8) , 
had a large influence upon the position and character of the Glacial 
deposits. 
The plateaux of Watt mountains, Caribou mountains, Birch mountain, 
Eagle mountain, and Buffalo Head hills are considered to be remains of 
the above-mentioned continuous plain which was dissected in pre-Glacial 
times. The remaining uplands were high enough to greatly affect the 
course of glacial movement during Pleistocene time. “At least three 
definite glacial lobes are apparent in the area. One extended up the 
valley of Hay river; a second swung west, south of the Caribou mountains, 
and probably sent tongues up the valleys of the Peace and Wabiskaw 
rivers; while a third lay in the basin of Athabaska lake with its tongue 
pointing up the valley of Athabaska river” (10). 
As the fronts of these lobes receded, the waters from the upper basins 
of the Hay, Peace, and Athabaska were impounded against them to form 
large post-Glacial lakes. From studies of terraces in the valleys of the 
main rivers, of elevated shore-lines on Great Slave lake, and from the 
results of topographic surveys, Cameron has designated four of these 
ancient lake levels, formed successively at 1,600 feet, 1,100 feet, 800 feet, 
and 700 feet above sea-level. The 1,600-foot level appears in the park 
area only along the southern border, on the margins of the Birch Mountain 
upland. The remainder was completely covered by the glacier with the 
exception of the higher parts of Caribou mountains. At the 1,100-foot 
level the shore w T as formed on the north, east, and south fronts of Caribou 
mountains. This lake extended far up the valleys of Hay, Peace, and 
Athabaska rivers, while the ice front had taken such a position that about 
half of Athabaska lake was exposed, and the remnants of the Peace and 
Hay River lobes were still apparent. The Peace lobe reached across the 
present valley of the Slave and over the upland nearly to Moose lake. 
The Hay River lobe stopped a short distance north of Buffalo lake. 
What appears to be the terminal morainic system formed at this ice 
front in the region w T est and southwest of Fort Smith has been located 
with a fair degree of accuracy by the writer and by Camsell (13). The 
Ninishith hills, converging to the northward near the place where they 
are crossed by Little Buffalo river, appear to be on the southern side of 
a re-entrant angle that lay between the remnants of the Hay and Peace 
River lobes. South of the Ninishith the system is expanded over many 
miles of territory lying between Pine lake and Moose Lake basin. Hills 
having a northwest and southeast trend between Moosehorn slough and 
Peace point are probably further extensions of this system. The terminal 
moraine mentioned by Cameron as occurring north of Buffalo lake, and 
making the dam that holds the latter, is the probable western limb from 
the angle. 
At the 800- foot level the ice had receded off Athabaska lake and 
covered only a portion of the eastern arm of Great Slave lake. The shore 
of the lake within the park area followed, in general, the margin of the 
Alberta plateau. The Buffalo Lake region was probably covered, as were 
91963-2 
