Where does the Obsidian we find come from?

Obsidian is a volcanic glass that was used by pre-European contact people all over North America. Known for its natural sharpness, ancient peoples sought the material for making tools for cutting and slicing. Additionally, it is easier to flintknap than the harder and more readily available materials local to Alberta.

As many of our readers know, there are no volcanoes in Alberta, so the obsidian is getting here either by trade or by the movement of people. Luckily for archaeologists, each source of obsidian in North America has a unique chemical signature, allowing us to trace where the material is coming from.

Finding obsidian in Alberta is rare, but over the past few years we have recovered three pieces (Figures 1-3) while working for Sundre Forest Products and Weyerhaeuser Pembina Timberlands Ltd. in the foothills region of the province. These artifacts were lent to Todd Kristensen at Alberta Culture and Tourism as part of the ongoing Alberta Obsidian Project. The artifacts we found were analysed using a technique called portable X-ray fluorescence.


The results show that two of the flakes (FbPX-10 and FaPr-6) track well with Yellowstone and one flakes tracks to Bear Gulch which is just outside of Yellowstone to the west. The source within Yellowstone is unknown, but it is assumed that it is the Cougar Creek source, which is the most wide used source.

Obsidian Sourcing Results

When we input the distance from FbPx-10 to Yellowstone National Park, we can see this artifact traveled 1,136 km and would take 231 hours to travel that distance by foot. Similarly, FaPr-6 was 1,033 km from Yellowstone National Park and FePr-4 was 979 km from Bear Gulch. This reinforces how valuable this material was for the First Nations of Alberta.

Distance between Yellowstone Park and FbPx-10


Top Ten Sites of 2018!

Now that all the reporting is done, we thought it was a good time to look back on some of the exciting sites we worked on from the past year. We find over 100 sites every year but these sites stand out either because we found interesting artifacts or the site is unique. It doesn’t matter how many points an archaeologist has found throughout their career, they will still get really excited when they pull a projectile point out of the their screen! In fact, compiling this list got me really excited to get out of the office and back into the field where an archaeologist belongs.

FbPv-29: Found while assessing a proposed cutblock for Sundre Forest Products near Fall Creek. The site is located on a small knoll overlooking a tributary stream. In our final test at the site we identified a feature in the corner of the test (Figure 2). This hearth/cooking feature has fire-cracked rock, several pieces of calcined bone (Figure 1), and discoloration of sediments. We sent a sample of the calcined bone recovered for carbon dating and received dates of: 2770-2750 Cal BP (820-800 BC) and 2845-2787 Cal BP (895-837 BC). That is one old camp fire!

Figure 1: Corner of positive test with feature

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Figure 2: Calcined recovered at FbPv-29

FcPf-26: Found while assessing a new phase for the Paradise Shores RV Resort on Buffalo Lake (Figure 4). The site is located on a small rise overlooking the lake to the north (Figure 3). While the site is small, we identified the tip of projectile point (Figure 6, Figure 5) and a variety of lithic materials including petrified wood. A number of different stone materials is a good indication that the area was used more than once to create a tool. When see the views from the Paradise Shores RV Resort, you can definitely see why a hunter would want to hang out here!

Figure 4: View of Buffalo Lake from south shore


Figure 3: View along the Buffalo Lake margin


Figure 5: Kristen holding the point tip

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Figure 6: Projectile point tip

FcPs-14: Found while assessing a gravel pit for Pidherney’s along the North Saskatchewan River valley margin. The site is interesting for the layers of history represented at the site including a precontact First Nations campsite (Figure 8) and an early 20th century dwelling. The dwelling is identified by the presence of depression, ceramic, metal, and glass artifacts. One piece of the glass has a purple tint which tells us the site probably dates to Pre-WWI. (Figure 7).


Figure 7: Purple glass found at FcPs-14


Figure 8: Sample of lithic artifacts recovered at FcPs-14


Found in the South Horburg region of the Sundre Forest Products FMA, the site is interesting for the recovery of two large tools and the large extent of the site (200 m). The tools were a quartzite cobble spall with a unifacial retouched edge and a large quartzite biface. In addition to the tools we found a variety of different lithic materials which suggests this was an area that was revisited year after year.

Figure 9: Biface recovered at FcPt-15


Figure 10: Unifacially retouched cobble spall


Identified on the relict valley of the Baptiste River for Sundre Forest Products. Eric found the base of a large tool, likely a knife or spear point (Figure 11). He was pretty excited to find it as we can see in the photo below (Figure 12)!

Figure 11: Tool base recovered from FdPv-8

Figure 12: Eric holding the tool base


FeQa-5 was found overlooking a tributary to the Brazeau River for Weyerhaeuser Pembina Timberlands. The site is extensive with beautiful views of the valley margin below. While testing the site out we found a variety of lithic materials including possible Knife River Flint.

Figure 13: View south from the site to the valley below

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Figure 14: Possible Knife River Flint recovered from FeQa-5


A very interesting site identified for Weyerhaeuser Pembina Timberlands near Edson, AB. The site was initially identified when we found an old corner of a cabin (Figure 15) on the crest of a small knoll. The knoll was quite prominent compared to the surrounding terrain and close to a lake, so we thought it had pretty high potential for a pre-contact component as well. A test near the cabin corner identified fire cracked rock, two hammerstones, and several pieces of lithic debitage (Figure 17, Figure 16)Sites like this either show that people at different times used the same landforms, or they may be evidence of continuous use by Indigenous people from pre-contact times through the fur trade. It would take more work to figure out which.

Figure 15: Cabin corner found at FkQa-10

FkQa-10_1 top_side view

Figure 17: One of the hammerstones recovered


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Figure 16: A sample of the quartzite debitage recovered


Found while assessing a cutblock for Vanderwell Contractors Ltd. Along the Athabasca River (Figure 19). This precontact campsite is huge (800 m) with great views of the River to the east. The site was found in a post-impact context (Figure 20). While it is normally required to obtain HRA approval prior to harvest, this block was assessed post-impact because a recent blowdown event made the block hazardous. The risks to the site are balanced by better visibility and artifact recoveries. We found lots of different materials, fire-cracked rock, a biface, two cores, and one Besant projectile point (Figure 18)!

Figure 18: Besant Projectile Point recovered


Figure 19: View toward the Athabasca River

Figure 20: Flake found in the exposed sediments


Pinto Creek Plateau:

Rather than a single site, this entry is for a group of sites on the Pinto Creek Plateau found for Sundre Forest Products this year. We found several sites on a variety of landforms ranging from low hilltops overlooking beautiful alpine meadows (FbPx-10, Figure 22) to high steep cliffs overlooking alpine stream valleys (FbPw-17, Figure 21). The coolest artifacts include a piece of obsidian (Figure 23) and a beautiful chert end scraper (Figure 24). The obsidian was sourced and the chemical signature matches the obsidian source in Yellowstone. The scraper narrow at the proximal end, indicating the use of a hafting element. Stay tuned for articles about the scraper and the obsidian sourcing!

Figure 22: View north of a meadow from FbPx-10 and the location of the obsidian artifact


Figure 21: View from FbPw-17 and a deeply incised river valley


Figure 23: Obsidian flake recovered from FbPx-10


Figure 24: End Scraper recovered from FbPw-17

FcPt-16 and FcPu-27:

Found on the old valley margin of the North Saskatchewan River for Strachan Forest Products. These two sites are separated by a steeply incised stream channel, located back from the current valley. At FcPt-16 over 70 artifacts were recovered from one 40 x 40 cm hole! Additionally we found a very unique spokeshave. Spokeshaves are usually made by retouching a flake, but this one was chipped and ground out of a smooth tabular rock (Figure 26). At FcPu-27 we found a large site with a variety of lithic materials, including one piece of salt-and pepper quartzite. Most interesting is a large Siltstone preform that we found (Figure 25).

Figure 25: Siltstone preform recovered at FcPu-27


Figure 26: Spokeshave recovered from FcPt-16


Birgitta Wallace

In honour of International Women’s day we will explore the life and studies of Birgitta Wallace. She is a Swedish-Canadian female archaeologist and expert on Norse archaeology in North America.

Born in 1944, Birgitta Wallace studied and received her degree in her home country, Sweden. She studied at Uppsala University and underwent field training in Sweden and Norway. In 1975, after receiving her masters degree in Pittsburg, Wallace moved to Canada and started her work with Parks Canada. She would continue to work with Parks Canada until retirement and she is best known for her work on the archaeological site L’anse aux Meadows.

Figure 1: Recreated Sod House at L’anse aux Meadows (Wikimedia Commons)


While it was long accepted that Christopher Columbus was the first non-aboriginal to set foot in the Americas, the Viking settlement of L’anse aux Meadows predates the landing of Christopher Columbus in North America by almost 500 years (dated around the year 1000 CE). L’anse aux Meadows was established as a Norse site due to definitive similarities between it and settlement structures found in Iceland and Greenland. While there are other suspected Norse sites in the New World, it si currently the only confirmed Viking settlement in North America south of Greenland. The area that the Vikings settled along the Atlantic coast is referred to as “Vinland” in Norse lore by explorer Leif Erikson. The exact locations and reach of Norse settlement remains a mystery. In particular, the location of a lost settlement referenced in Erik the Red’s saga continues to elude researchers. The story of this settlement, referred to as Hop, captured Wallace’s attention and, even after her retirement, she continues to theorize about Hop.


Figure 2: Birgitta Wallace in Greenland (National Post)

In 2018, Wallace claimed only a particular area of New Brunswick can accommodate all the criteria found in the saga writings. Wallace theorized that due to the “(abundant) lumber, masses of salmon, halibut, and grapes” referenced in Erik the Red’s Saga, New Brunswick is the most likely candidate for the location of Hop. Other areas theorized as possible locations – New York, Maine, New England – lack one or more of these resources. Perhaps her most compelling argument, was that she identified a species of plant at the site of L’anse aux Meadows which is exclusively native to New Brunswick.

While we may never know the true locations of Vinland or Hop, rest assured Birgitta Wallace will continue to search for us. Her story is one of a career archaeologist who continues to stoke the fires of our curiosity well after retirement. If you would like to know more about the adventures of Women in Archaeology you can read “Ladies of the Field: Early Women Archaeologists and their search for Adventure.

If you share Wallace’s insatiable interest in Vikings, you can read her many works on the topic and make sure to visit the Vikings exhibit at the new Royal Alberta Museum in April.

Ground Penetrating Radar

Ground-Penetrating Radar (GPR) is the process of sending radiowaves through the ground. As these radiowaves pass through the ground, any change in the subsurface materials will cause some energy to be reflected back to towards the surface while the remaining energy continues deeper. This information is recorded by a receiver which records the time it takes the wave to travel from the source, reflect off the buried object or disturbance, and travel back to the surface. The receiver converts this signal into a depth for the disturbance or object under the ground.

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Figure 1: Brian Leslie walking a transect with the GPR

The ability to map and record information below the earth’s surface without excavating is a valuable tool to an archaeologist. The excavation of archaeological sites is a destructive process, so having a non-invasive way to analyze and interpret sites is sometimes necessary. This is particularly important when dealing with sensitive cultural remains and unmarked graves.

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Figure 2: Corey Cookson and Liam Wadsworth surveying for unmarked graves

As part of an Archaeological Society of Alberta project, Tree Time Services Archaeologists, Corey Cookson and Brian Leslie, and University of Alberta Graduate Student, Liam Wadsworth, completed a GPR scan of an area identified by a local community as having possible unmarked graves. The team spent the afternoon surveying a grid to identify possible grave-shaped anomalies. The data was analyzed and the GPR scans revealed several clear grave-shaped anomalies 1.5 m beneath the surface. Some of the grave-shafts were narrow and may have contained a single individual (Figure 3, #1), while others were wider and may represent a burial pit with multiple individuals (Figure 3 #2, at least 5 m wide). This larger internment may have been the result of mass burial. It was speculated that these graves were dug around the time of the First World War and the Spanish Flu pandemic.


Figure 3: Radargram with pit-shaped anomalies


Figure 4: Same Radar gram with interpretation of pit-shaped anomalies

Purple Glass = Pre World War I

When we find post-European contact sites in Alberta we find a variety of historic resources including: cabins, ceramics, metal, and glass. The style of each of these can be a good indication of age and, in particular, glass has several features we look for. This includes molds, pontil marks (Figure 2), lip forms (Figure 1), and colour.

Figure 1: Bottle lips crudely applied by hand prior to 1880s when lipping tools invented (Source: Wikimedia Commons)


Figure 2: Pontil mark on the bottom of glass bottle on all bottles dated before 1860 (Source: Wikimedia Commons)

This year, while assessing a gravel pit along the North Saskatchewan River, we found a multi-component site (FcPs-14) with both a pre-European contact First Nations campsite and a post-European contact dwelling. In addition to the typical lithic debitage, we found a cabin depression, ceramics (Figure 3), metal (Figure 4), and glass artifacts. One shard of glass caught my eye because of the purple tint to the glass (Figure 5).

Figure 3: Ceramic recovered from FcPs-14

M1182_modifiedFigure 4: Nail recovered from FcPs-14


Figure 5: Purple glass recovered from FcPs-14

From 1885 to 1914, manganese dioxide was used as a clearing agent by glass makers to make sure the glass remained clear. However, when exposed to the sun over time, the manganese dioxide in the glass will cause the glass to turn a purple tint. The main source of this clearing agent was Germany. This supply was cut off with the outbreak of World War I. After World War I, selenium became the preferred clearing agent. When exposed to the sun’s rays, selenium will turn glass yellow.

By recovering this piece of glass, we can make a reasonable interpretation that this component of the site dates to before, or shortly after, 1914. Even a seemingly commonplace artifact like a shard of glass can tell us a lot about a site.

Rat’s Nest Cave – Pictographs

Last year I visited a very interesting site located near Canmore, AB. The Rat’s Nest Cave is accessible through the touring company, Canmore Cave Tours, and can be visited all year round. With the help of my guide, Brent, I rappelled 18 m into the cave and squeezed through many tight water carved gaps and tunnels. Eventually you reach “the grotto” where you can hang out by a crystal clear pool and several beautiful stalagmites and stalactites.

Left: Repelling into the cave.  Right: One of the many squeezes you will experience!

Also in the cave are many animal bones dating to approximately 7000 years ago and, although I didn’t see any while on the tour, several stone tools dating to 3000 years ago. One of the most fascinating aspects of the cave are the pictographs located at the entrance of the cave. Inside the cave, are several small rock paintings that indicate the cave was of cultural significance for the First Nations people possibly for thousands of years. My guide also informed me that there are several pictographs on the outside of the cave above the entrance but due to years of weathering they are not visible to the naked eye.

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Assemblage of animal bones found in the cave
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One of the rock art images inside the entrance to the cave

Luckily, recent advances in technology allow us to digitally enhance rock art paintings. A process called Decorrelation Stretch or simply D-Stretch is currently being used by archaeologists and rock art researchers to enhance even the faintest of pictographs. The process works by increasing differences in hue and stretching the contrast for each colour variance. When D-stretch is used to enhance the image of the entrance of the Rat’s Nest Cave, a series of handprints can be seen going up the wall.

wall above entrance
Left: Normal image of the wall above entrance.  Right: D-Stretch image of wall above entrance
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One of the handprints isolated (Photo Credit: Jack Brink)

Continuity – Buffalo and Sucker Lake Region

Before 2013, archaeological survey in the Sucker and Buffalo Lake regions only identified three sites.  In contrast, just 5 km east, in the Logan and Clyde River systems, around 25 sites had been found. This is likely due to the location of developments being surveyed, but it may also reflect older archaeological survey methods.  The dense river systems and the sandy sediments typical to these two areas really increase the archaeological potential.  This means there are numerous sites that have yet been identified by archaeological survey.

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When Millar Western Boyle and Alberta-Pacific submitted new forest plans for this region, we knew we could improve the archaeological understanding of the area. Over two field seasons we put in 477 shovel tests and surface inspections. We increased the sites in the area by 14 sites!

Not only did we find sites, but we found two artifacts that really help us understand the people who used this area by helping us determine a date and possible trade connections. Two artifacts, one projectile point and one knife, were the most interesting finds of the survey.

  • The projectile point is the base of a dart thrown by an atlatl. This is an older technology than the bow and arrow, used prior to 2000 years ago. The point is likely Scottsbluff style which is dated up to 8,000 years ago. This atlatl dart point is also made of Knife River Flint. Knife River Flint is a very significant material that only comes from a quarry site in North Dakota (over 1300 km away!).
  • The knife is an asymmetrical corner notched siltstone knife. The only known knife typologies in Alberta belong to the Cody Complex; however, unlike this knife, the stems of Cody knives are usually straight and have a flat base. Further research at this site and about this artifact may significantly alter our knowledge about knife manufacture and technology in Alberta. The style may also be representative of a knife style found in other regions of North America which would suggest travel or trade.

Cabins and historic trails were also identified during the assessment. These are from late 19th to early 20th century occupation of the area, possibly associated with First Nation or Metis use and of cultural significance. At site GgOw-10, two cabins were present, one older than the other. We know this because of the way the two cabins were constructed: one with chainsawn logs and the other with an axe. This is indicative of significant, long-term land use in the Buffalo Lake area. At this site, many metal and glass artifacts were also observed, including a wagon wheel hoop, cans, pots, pans, and a cast iron stove. In addition, we identified wagon trails used to travel along between Buffalo Lake and other nearby settlements such as Philomena.

The area is still being used today and remains an area of importance to local First Nations. A prayer tree was identified while surveying a cutblock along a tributary stream. The cutblock was dropped from the harvest plan due to the presence of the prayer tree. The tree was a jackpine with a red and white pieces of fabric tied to the trunk. The prayer tree can indicate an area where a ceremony took place or an area with medicinal plants. A photo of the tree was not included out of respect for Indigenous traditions.

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Reid documenting an area near the prayer tree

We always look forward to returning to areas we have surveyed in the past.  Continuous archaeological survey helps us better predict where other sites are likely to be and fills out our understanding of how landscapes were used over time.