After a few thousand years, most of the archaeological record in Alberta has been winnowed down to pieces of rock used to make tools. Organic artifacts, structures, and other less durable things generally don’t survive thanks to erosion and decomposition. To maximize the information we can pull from those pieces of stone, the Alberta Lithic Reference Project (ALRP) was formed by a consortium of archaeological consultants, heritage managers, geologists, students, and university researchers. The goals are to accurately and consistently identify the types of raw materials that pre-contact people used to make stone tools. Why is this important? Specific types of rock were traded and moved widely across the continent and serve as valuable indicators of cultural relationships and/or human mobility patterns.
Alberta occupies a unique position in North America with rivers that drain to the Arctic Ocean (Peace and Athabasca Rivers), Hudson Bay (the Saskatchewan Rivers), and the Gulf of Mexico (the Milk River). The proximity to prairie resources (like bison) also attracted people from west of the continental divide that runs through our Rocky Mountains. Alberta therefore bears records of ancient cultural exchanges between people from coastal B.C., subarctic N.W.T., the Dakotas, Wyoming, Idaho, and Manitoba, to name a few. It’s a fascinating place to reconstruct contact between nations from the Plains, Rocky Mountains, Boreal Forest, Tundra, and Eastern Woodlands. Alberta is also a crucial place to study how the continent was settled. Some of the earliest humans in the New World may have migrated through a corridor of land that extended through Alberta and was bordered by ice to the west and east around 13,000-12,000 years ago. The archaeological record of stone tools in this province may hold keys to unlocking mysteries of how people moved through North America.
One of the biggest problems associated with the use of stone tools to reconstruct trade and mobility is the inconsistent use of terms to identify materials. Some archaeologists have different criteria for defining and naming raw materials that outcrop in Alberta, as well as materials that occur elsewhere in North America and were brought into the province. A major objective of the ALRP is to provide a scientific basis for identifying raw materials using mineralogy and geochemistry. We employ X-ray fluorescence, neutron activation analysis, x-ray diffraction, raman spectroscopy, near-infrared spectrometry, and thin section analyses to accurately determine what raw materials are. These provide types of fingerprints that archaeologists can then use to confirm that a raw material discovered at an Alberta site is in fact from a particular outcrop or quarry (a place where raw materials were collected). The second major objective is to provide photographic libraries that archaeologists can compare with materials they’ve recovered. When used in combination, the data help us understand who was interacting with who, and how Alberta was situated in a network of cultural contact that spanned North America.
The ALRP currently has 12 teams of researchers studying particular raw materials that either outcrop in Alberta (and were used by pre-contact people to make stone tools) or were brought into the province from foreign outcrops. What have we discovered so far? For at least 8000 years, people from the N.W.T. traded or brought a material called Tertiary Hills Clinker over 1000 km into northern and central Alberta. For around 2500 years, groups from coastal B.C. traded jade over 800 km across the Rockies into Alberta. And for at least two major intervals (around 8000 years ago and 2500-2000 years ago), people maintained particularly strong connections to North Dakota based on the presence of a distinct raw material called Knife River Flint. Lastly, based on obsidian sourcing studies (using fingerprints to tie obsidian artifacts back to their volcanic origin), the earliest inhabitants of Alberta likely came from the south. Preliminary work by the ALRP is putting the discipline on better footing to answer significant questions about pre-contact people in North America. We hope the data add value to Alberta’s archaeological record and attract researchers from across the globe.
Three papers have been published about the Alberta Lithic Reference Project: Tertiary Hills Clinker, jade, and Beaver River Sandstone. A growing photographic library of images are available through a Facebook group (Alberta Lithic Reference Project) that researchers are welcome to join, debate, and contribute to. Look for an upcoming paper about Knife River Flint from the Dakotas in the next issue of the Archaeological Survey of Alberta’s Occasional Paper Series (free for download).
Written By: Todd Kristensen (Regional Archaeologist, Archaeological Survey of Alberta)