Glaciation of the High Uintas Primitive Area, Utah with emphasis on the Northern slope

The High Uintas Primitive Area is located in the western Uinta Mountains in Utah, near the Wyoming border. The drift morphology, vegetation, soil development, stratigraphic relations, and erosional modification show that during the Pleistocene there were at least four major glacial advances in the Uinta Mountains: the Little Dry, Blacks Fork, Smith Fork, and neoglacial. This investigation thoroughly studied the last three glaciations and showed that each glaciation can be further subdivided. -Two stades of the Blacks Fork Glaciation were identified along three river systems, but only one stade, is present in three others. Within the Smith Fork Glaciation a fourth stade, the Agassiz Stade, has been added to the three stades previously recognized. This youngest is further subdivided into three substades. The Neoglacial episode is divided into four stades which are here named: Dead Horse, Tokewanna, Ostler, and Priord. The study area is one of the few localities in the northern hemisphere where four stades of Neoglaciation have been recognized. During the Little Dry Glaciation an extensive piedmont glacier formed on both slopes of the Uinta Mountains. Valley glaciers advanced slightly beyond the mountain fronts on both slopes during the Blacks Fork Glaciation. The first three stades of Smith Fork Glaciation are represented at progressively higher elevations within the mountain front. During the Agassiz Stade and the first three Neoglacial stades, the northern slope was glaciated at higher elevations, whereas the southern slope was nearly clear of glacial ice. The author obtained data by investigating other glaciated areas in the western United States and by aerial photographic interpretation. These data helped to develop a tentative correlation of the glacial chronology of the High Uintas with the other glaciated areas. The author confirms Richmond's correlation that the Blacks Fork and Smith Fork Glaciations correlate with the Bull Lake and Pinedale Glaciations of the Rocky Mountains. The Neoglaciation stadial correlations are as follows: Dead Horse and Tokewanna correlate with Temple Lake I and II, respectively; the Ostler with the Audubon of the Colorado Front Range, and the Priord with the Gannett Peak. Typical glacial features occur in the study area. Their characteristics vary with age. The Blacks Fork glacial features are subdued except for the large end moraines. The soil depth ranges from 35 to 70 inches. The successive Smith Fork moraines become progres­sively smaller, more steep, and less weathered at higher elevations. The soil depth ranges from 5 to 55 inches. The Neoglacial moraines occur only in the upper cirques. The Dead Horse moraines are three to ten feet high and are breached at some locations. The soil depth is four to six inches. Trees cover 30 to 60 percent of the moraines. The Tokewanna moraines are 50 to 100 feet high and are rarely breached. The soil depth is one to two inches. Trees cover 20 to 40 percent of the moraines. The Ostler moraines are 15 to 40 feet high and are not breached. The soil depth is zero to one inch. There is a scattered tree cover. There are no Priord moraines, but there are Priord rock glaciers. The study area has many varieties of periglacial features. Talus landforms are identified throughout the study area. Solifluction deposits occur on slopes void of vegetation. At the highest elevations active and inactive felsenmeer and inactive patterned ground are dominant. Boulder streams and fields are numerous on the southern slope but rare on the northern slope. Both cirque-floor and valley-wal rock glaciers were identified on both slopes. Many of the periglacial deposits were identified as to age. These data were important in the development of the glacial chronology of the High Uintas.