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TitleSurficial geology of the Drumheller area, Alberta
AuthorStalker, A M
SourceGeological Survey of Canada, Memoir 370, 1973, 122 pages (3 sheets),
PublisherGeological Survey of Canada
MapsPublication contains 3 maps
Map Info.surficial geology, glacial features, 1:250,000
Map Info.surficial geology, overburden thickness, 1:250,000
ProjectionUniversal Transverse Mercator Projection
Mediapaper; on-line; digital
RelatedThis publication contains Stalker, A M; (1973). Surficial geology, Drumheller, west of fourth meridian, Alberta, Geological Survey of Canada, "A" Series Map no. 1336A
File formatpdf
Lat/Long WENS-114.0000 -112.0000 52.0000 51.0000
Subjectssurficial geology/geomorphology; alluvium; drumlins; eskers; glaciation; ice movements; meltwater channels; moraines; murdlins; outwash; wisconsinian glacial stage; Bearpaw Formation; Edmonton Formation; Hand Hills Formation; Paskapoo Formation; Quaternary
Released1974 03 01; 2015 08 06
AbstractThe Drumheller area of central Alberta covers about 6,000 square miles directly northeast of Calgary. Although the Rocky Mountain Foothills are nearby, only the most westerly parts of the area were affected by Cordilleran glaciers. Laurentide glaciers, on the other hand, strongly glaciated the whole area several times during the Quaternary Period. Information on early glaciations is scanty as most of the area lies near the drainage divide between Red Deer and Bow Rivers-a region ill-suited for preserving early glacier deposits from destruction by subsequent glaciers. Thick sequences of drift have survived in the preglacial Bow Valley, which crosses the southwestern and southeastern parts of the area, but they are poorly exposed. In the southeast, drift overlies enormous deposits of preglacial (Pliocene and Pleistocene) gravel and sand.

The retreat and the deposits of the Classical Wisconsin glacier are described in detail. The chief feature during the over-all retreat was the lnnisfail rejuvenation, which corresponds to one of the Wisconsin stades. During this rejuvenation, the ice thickened at least 500 feet and advanced as much as 125 miles. Most of the spillways in the region developed either during the glacial retreat that immediately preceded this readvance, or during the recession of the still earlier, pre-Classical Wisconsin glacier. They were reoccupied by meltwater streams following the Innisfail Readvance.

Over much of the west half of the area the glacier retreated uphill, retained movement until it had become thin, and was effectively drained. Elsewhere it retreated downhill, stagnated while still fairly thick, and, for the most part, was saturated with water. The result in the western districts was the abundance of esker ridges, ice-flow markings, and spillways, along with extensive areas of till plain and outwash, that form a vivid contrast to the expanses of hummocky moraine and lake plain found in the central and eastern districts.

The term 'murdlin' is introduced to designate an elongate ice-flow feature, previously undescribed. A 'murdlin' resembles a drumlin both in size and relation to ice movement, but it differs markedly in shape and genesis.