View down Nose Creek in NW Calgary

Nose Creek today is a calm, meandering stream that winds its way down a peaceful valley in northwest Calgary and is a popular green space for Calgary's growing population. The creek is clearly much smaller than the valley it occupies (a 'misfit' stream) and was not capable of eroding a valley of this size. The current that created the valley now confining Nose Creek was in force back at the end of the last ice age, when large quantities of meltwater spewed out from retreating ice sheets, at times completely filling up this valley. The valley that confines Nose Creek is termed a 'glacial outwash channel', a relic of a climate long ago. Other examples of ancient outwash channels in the Calgary area include the Fish Creek valley, the Nose Creek valley from 17^th Avenue north to Airdrie, and the Big Hill Creek valley that houses the Cochrane Ranche Provincial Historic Site.

Stop 3b W. Nose Creek

Quartzite erratic on top of a sandstone quarry in W. Nose Creek

The large rock ('Split Rock') that rests on top of the small cliff above West Nose Creek is a glacial erratic that began its journey east on a large valley glacier from a valley near Jasper 17 000 to 20 000 years ago. Today, many erratics like this one, including the famous 'Big Rock' near Okotoks, form part of an erratic train that extends from Jasper all the way south to the Montana-Alberta border. This erratic train represents a line where ice flowing from the east and ice from the western mountains met to form a medial moraine.

The small cliff at the edge of the creek is an outcrop of Paskapoo Formation sandstone, which dates back to the Early Tertiary (Paleocene). This cliff was excavated as a potential sandstone quarry, one of many quarries from which Calgarians acquired the sandstone blocks used to construct many of the older heritage buildings that still exist in the downtown area.

Click on a dot to continue the tour:

Legend

	Holocene	Present - 10,000 years ago
	Quaternary	10,000 - 25,000 years ago
	Tertiary	25,000 - 65 million years ago
	Mesozoic	65 - 245 million years ago
	Paleozoic	245 - 670 million years ago