Auyuittuq National Park of Canada

Geology

Thor Peak
Thor Peak
© Parks Canada / Christian Kimber

Visitors to Auyuittuq will likely be awed by the impressive display of rock in the park - from the sheer rock faces of granite peaks, to ragged tumbles of giant boulders, and endless deposits of glacial debris. A key feature of the park is the Penny Ice Cap, a vast, 6000 km2 expanse of ice and snow. Outlet glaciers - rivers of ice, some of which are up to 25 km long - radiate from the ice cap in several directions.

Early Geological History

Baffin Island forms the northeastern edge of the Precambrian or Canadian Shield, the ancient stable core of the North American continent. The Precambrian era is the oldest period of geological time, going from 570 million years ago back more than 3.5 billion years to the oldest rocks known on the planet. Most Precambrian rocks have been metamorphosed (altered by intense heat and pressure) at various times during this period. The end product of metamorphism is granite.

In the Auyuittuq - Cumberland Peninsula region, the oldest rocks were formed around 2.8 billion years ago, and metamorphosed into granite about 2.5 billion years ago. Early in the Paleozoic era, around 550 million years ago when life forms were first spreading across the earth, the eastern Arctic was covered by a shallow sea and thick layers of marine sediments were deposited over the bedrock. Around 60 million years ago, a major upheaval occurred as continental drift caused the separation of Baffin Island and Greenland. The Cumberland Peninsula was uplifted and subsequent erosion removed most of the sediments, exposing the bare rock once again. The mountain peaks left in the park today are the highest on Baffin Island, as well as some of the highest in the Canadian Shield.

Effects of Glaciation

Highway Glacier from Mount Battle
Highway Glacier from Mount Battle
© Parks Canada

Auyuittuq's unique and spectacular landscape can be attributed to the more recent erosive influences of ice and glaciation. The area has been scoured by both continental ice (the Laurentide Ice Sheet of the Wisconsin glaciation, which began its retreat from the area around 8000 years ago), and localized alpine or cirque glaciers. It is thought that the northwest portion of the Penny Ice Cap might be a remnant of the Laurentide Ice Sheet.

Along the coast, glaciers have incised the valley floors below sea level, creating deep, narrow fiords with vertical walls up to 900 m in height.

Glacial features that can be seen in the park include:

  • Moraines - ridges or mounds formed by rock debris that were transported by moving ice and deposited at the margins of glaciers. End moraines show the farthest point of a glacier's advance, while lateral moraines show the location of the glacier's sides.
  • Cirques - bowl-like hollows carved out by glaciers in the tops of mountains. Some cirques are ice-free, while others are still occupied by glaciers. Many of the park's sharp mountain peaks and ridges were carved by cirque glaciers.
  • Sand Deposits - Created by the erosive actions of ice, wind, and water. Sand and other fine particles are carried by the wind from moraines and outwash deposits.
  • Perched Boulders - Large boulders sitting atop small rocks, deposited by retreating glaciers
  • Talus or Scree Slopes - cone-shaped accumulations of rocks pried loose from steep glacier-scoured valley walls by frost action. Active talus slopes are unstable and could be dangerous to hikers. Rock surfaces that are lichen-free provide clues that the slope is still active and prone to fresh rockfall.

Geological Points of Interest in Auyuittuq:

  • Akshayuk Pass (Akshayuk Akutinga) - This 97 km ice-free trough cuts through the mountains between Cumberland Sound and Davis Strait. Carved out by the continental glaciers of the last ice age, it has been used as a traditional travel corridor by the Inuit for thousands of years. Today it is the park's most popular hiking destination.
  • Mount Overlord (Pangniqtup Qingua) - This majestic peak (1490 m) stands as a sentinel guarding the southern entrance to Akshayuk Pass. Below Overlord, where Pangnirtung Fiord meets the Weasel River, tides can fluctuate up to 10 metres.
  • Crater Lake (Aqulutaqrusiq) - This beautiful, circular, greenish-blue lake is perched on the west side of the Weasel River, approximately 5 km southwest of the Windy Emergency Shelter. From the main trail, it is hidden by a circular ridge of gravel and sand which surrounds it. This ridge is the end moraine of the glacier above the lake. It marks the limit of the glacier's last advance, which occurred about 100 years ago. Now that the glacier has melted back, the moraine acts as a natural dam, collecting sediment-laden meltwaters from the glacier. To view the lake, climb from the main trail to a higher elevation.
  • The Arctic Circle (Ukiuqtaqtuup) - This imaginary line, marked by a monument along the trail, is at the latitude of 66º 33 ½' North. At any point along the line there are 24 hours of daylight on June 21, and 24 hours of dark on December 21.
  • Schwartzenbach Falls (Qulitasaniakvik) - This white torrent of water, located on the west of the Weasel River across from the Arctic Circle, plunges 660 metres down a steep mountainside to the Weasel River. Its Inuktitut name means "the place to get caribou skins". Long ago, Inuit hunters climbed past these falls to look for caribou in the valleys beyond.
  • Thor Peak (Qaisualuk) - Approximately 27 km down the trail from Overlord, near the Thor checkpoint, Thor Peak can be seen soaring 1675 metres above the valley floor. Named after the Norse god of thunder, it has a cliff face of 1 km, the longest uninterrupted cliff face in the world.
  • Summit Lake (Tasiruluk) - This large lake marks the highest point in Akshayuk Pass. Like Crater Lake, it was formed by the pooling of glacial meltwaters in an end moraine. Glacial waters from this lake flow both north and south into the Owl and Weasel rivers, dropping 500 metres before reaching the Arctic Ocean.
  • Mount Asgard (Sivanitirutinguak) - Located near the summit, this distinctive mountain (2015 m) is one of the park's most famous. Rising from surrounding glaciers, the flat top of its two cylindrical towers has been a goal for mountaineers from around the world.
  • Turner and Highway Glaciers (Auyuittuit) - These glaciers radiate outwards from the Penny Ice Cap like enormous tentacles. In imperceptibly slow motion, these great rivers of ice creep down from the high plateau of the park's interior towards the valley floor, pulled by gravity and the weight of the ice.
  • Owl River Valley (Inatiavaluk) - This scenic tundra valley lies in the northern half of Akshayuk Pass between Glacier Lake and North Pangnirtung Fiord. This area is not hiked as much as the southern half of the pass. Here the landscape is permanently frozen except for a thin layer on the surface. Hikers should be cautious when traversing the mud along the Owl River since some sections may thaw deeply enough to create waist-deep quagmires with dangerous quicksand-like properties. The valley was named after the snowy owls which might be seen during years of high lemming populations. Antlers on the valley floor tell of earlier times when the rich tundra vegetation provided habitat for caribou herds.
  • Penny Highlands - The park is dominated by these ancient peaks of Precambrian granite. Reaching heights of up to 2100 m, they are the highest on Baffin Island, as well as the highest in the Canadian Shield. Most of the highlands are covered by the solid ice of the Penny Ice Cap, which is 300 m thick and covers an area of 6000 km2.