A new study may have answered a long-standing mystery by pinpointing the rough date of the earliest known humans in Canada’s oil sands region.
In a recently published paper, professor Robin Wojwitka of McEwan University in Edmonton, a combination of archeology and geology reveals that people lived around Fort McMurray in Alta at least 11,000 years ago and possibly 13,000 years ago. It is said that it became
“People were in the Fort McMurray area very early on,” says Woywitka.
“Fort McMurray has been connected for thousands of years.
Scientists have long known that the region has a long human history. The site, known as the Ancestral Quarry, has yielded millions of artifacts since it was discovered in the 1990s.
However, it was difficult to put the date.
No standard methods, such as radiocarbon dating, have emerged. The region’s acidic soils destroy the organic matter on which these techniques rely.
Scientists may be able to use earth’s sedimentary layers to date artifacts. However, the area is more stable with less sediment deposits.
So Wojwitka and his colleagues tried something new.
They took satellite maps that revealed surface topography to within a few square meters. They used that information to find the most likely locations of deposits, of which he selected five. One of them was in an ancestral quarry.
Deposits from these sites were dated using a technique called infrared stimulated luminescence.
This technology takes advantage of the fact that grains of sand collect small radioactive particles within their pores. These particles degrade at a known rate when exposed to light. So the longer it is buried, the more particles there are.
Infrared radiation causes these particles to emit energy. It can be measured to reveal when the host’s grain of sand was buried, and whether stone tools were buried alongside it.
In this case the answer was 12,000 years.
“It’s more uncertain than radiocarbon dating, but it’s better than nothing,” Woywitka said.
This finding put those early people at the very beginning when that part of the world became livable. The first inhabitants moved there within centuries after devastating floods drained Glacial Lake Agassiz, a vast inland sea that once covered nearly all of present-day Manitoba and half of present-day Ontario. would have done
Humans first arrived in North America not too long ago, and most archaeologists believe it happened about 16,000 years ago.
They would have found landscapes far removed from the lush boreal forests and lush wetlands that now cover much of northern Alberta.
“People are dealing with environments that are very different from what we see today: open, dry, cold,” says Woywitka. “Probably tundra or grasslands.”
They were probably hunting bison, Wojwitka said. Beyond that, very little can be said.
“Whether they came from the north or the south, we don’t know.”
Despite the proliferation of artifacts, scientists are unable to fit them well into the cultural toolkits of other prehistoric peoples. The existence of material from other parts of the continent suggests trade networks with other regions, but little is known about them.
One thing I can say.
Woywitka points out that the floods that drained Agassiz exposed both the fine tool-making stones that drew people to the area and the oil sands that drew thousands of modern inhabitants.
“People came 13,000 years ago to get that thing,” he said. “We are going to Fort McMurray today for resources.”
Bob Weber
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