Description of Historic Place

This complex of archaeological sites and natural features is located east of the Athabasca River in the Muskeg River valley, approximately six kilometres northeast of Fort MacKay. It consists of a series of surface and near surface outcrops of bedrock, along with a vast array of associated artifacts representing extraction and processing of Beaver River Silicified Sandstone, the principal tool stone found in archaeological sites throughout Alberta's Oil Sands region. The site complex includes a series of related habitation and task-specific use locales. The designation area occupies 198.55 hectares and encompasses portions of Sections 27, 28, 33, 34-94-10-W4M. It comprises a number of archaeological sites, including two outcrops of fine-grained Beaver River Silicified Sandstone and associated quarrying and workshop locales, areas of potential for additional deeply buried archaeological deposits, and a portion of the surrounding terrain to maintain a sense of place.

Heritage Value

The Quarry of the Ancestors possesses heritage value for its excellent potential to yield additional information on the ancient human use of Alberta's Oil Sands region.

The Quarry of the Ancestors is the principal currently known source location for obtaining in-situ, fine-grained Beaver River Silicified Sandstone, the dominant tool stone found in archaeological sites throughout the Oil Sands region. The landscape that is fundamental to the character of the site and its use was formed by a catastrophic outflow from Glacial Lake Agassiz, the largest inland lake in the world, approximately 9,800 years ago. The massive release of water associated with this event scoured the Lower Athabasca River valley and created the braided channel deposits, gravel bars, and sinuous ridges that structured the unique ancient land use pattern recognized within the core area of the Oil Sands region. Revegetation of this well-drained landscape created an open, productive ecosystem that was extremely attractive to big game and their prehistoric hunters. These conditions, coupled with the exposure of high quality stone tool source material, provided the means and opportunity for the intensive prehistoric human use of this region. Archaeological evidence indicates that the site complex was used for both quarrying Beaver River Silicified Sandstone and crafting it into tools. Time-diagnostic specimens recovered to date suggest that the principal use of the Quarry of the Ancestors occurred between 9,800 years and 5,500 years ago. The site complex represents a focal point for one of the most intensive ancient uses of boreal forest regional environments yet identified in Canada, reflecting a unique set of geological and ecological conditions that existed during early to middle Holocene times.

Early work on the Quarry of the Ancestors suggests that the site complex could illuminate a number of significant research questions on the ancient history of northern Alberta. The Quarry of the Ancestors possesses a high density of artifacts and sites reflective of a wide range of ancient cultural practices. Among the most intriguing cultural materials excavated have been microblade artifacts, a comparatively rare form of this technology in the Oil Sands region, and spear points containing blood residue. Stratified ordering of some cultural materials has also been discovered, along with a number of culturally diagnostic specimens. Additionally, the current environment of the Quarry of the Ancestors retains some of the landscape features formed as a result of the Glacial Lake Agassiz outflow. The preservation of the Quarry of the Ancestors will be essential in reconstructing ancient social life across the region.

Source: Alberta Culture and Community Services, Historic Resources Management Branch (File: Des. 2172)

Character-Defining Elements

The character-defining elements of the Quarry of the Ancestors include such features as:
- location in the Muskeg River valley on the eastern margin of the Glacial Lake Agassiz north-western outwash event flood zone;
- significant landscape features that structured the unique ancient land use pattern recognized throughout the Oil Sands region, including braided channel deposits that consist largely of boulders and coarse gravels; rolling, sand-draped gravel bars separated by sand-filled remnant channels; and the sinuous nature of the ridges;
- near-surface, in-place bedrock formations containing Beaver River Silicified Sandstone and abundant associated cultural materials reflecting primary extraction and initial processing of these stone formations;
- a complex of archaeological sites where raw materials extracted from the quarry were used in stone tool production and subsistence-related activities;
- archaeological resources that occur in a deeply buried context, with multiple soil horizons, reflecting an accumulating sediment sequence;
- microblade technology found at one of the main sites in the Quarry of the Ancestors designation area, one of only two known occurrences in the Oil Sands region of in-situ assemblages containing detailed expressions of this technological tradition;
- localities within the Quarry of the Ancestors that provide evidence that the use of this site complex extended into now water-saturated muskeg landforms that stretch between more typical, elevated site areas, offering the possibility of recovering organic components of the archaeological record;
- the substantial number of chronologically sensitive and culturally diagnostic specimens that have been recovered and the high probability of recovering more;
- blood residue retained on recovered stone artifacts and the possibility of discovering more;
- the potential for additional information with respect to ancient human use of Alberta's Oil Sands region.