Picture of the Week – Fawn

When working east of Nordegg in 2014 Vince found this little fawn. The spots on the fawn are for camouflage, to help him blend into his environment. These spots will last for the first 90-120 days of his life and will fade when he grows his warmer winter coat.

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Finding Archaeological Sites from the sky using high-tech advances in archaeology

In recent months, news feeds have been erupting with stories of “Lost Maya Cities discovered using LiDAR”, “revealing the secrets of Stonehenge using LiDAR”, “LiDAR uncovers ancient city near Angkor Wat”, and the popularity of “space archaeologist” Sarah Parcak, but this technology is not limited to finding the remnants of “lost civilizations” in far reaching corners of the globe. LiDAR is used by archaeologists in Alberta to assist in the locating of potential archaeological sites that are threatened by development.

Figure 1. Marching Bear Effigy Mounds Lidar Imagery (Wikimedia Commons)
Figure 1. Marching Bear Effigy Mounds LiDAR Imagery (Wikimedia Commons)

Light detection and ranging (LiDAR) is the process of mounting a laser on an aircraft and bouncing light pulses off the ground and measuring the time it takes for the laser to return. The process can take 2000-5000 measurements per second and makes the surface appear treeless, revealing surface features that cannot be seen using simple satellite imagery or aerial photos (Figure 1). However, using LiDAR to find archaeological sites in northern Alberta is not as easy as it can be in other parts of the world. LiDAR is great for identifying building structures, walls, and other features common of archaeological sites in other parts of the world. In northern Alberta these features are absent from Indigenous archaeological sites. To study the human history of northern Alberta prior to European contact we have to look at the landscape and identify landforms that would have been suitable for camping and hunting activities.

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Figure 2. Satellite imagery of ridge overlooking marsh
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Figure 3. LiDAR hillshade of the same ridge

In the above images, the first image is a satellite image of a ridge where we found an archaeological site (Figure 2). With just satellite imagery the area appears to be predominantly flat which is not a good area to camp or hunt. This is because the area would be thought to be poorly drained and with limited visibility of the surrounding terrain. When using LiDAR imagery (Figure 3) we notice there is a complex of distinct hills and ridges that would be ideal for making camp.

This technology has revolutionized the process of finding archaeological sites in Alberta and is revealing more about the history of people in the boreal forest. The ability to pinpoint the best landforms without having to do extensive on-the-ground survey has greatly increased the inventory of sites found in northern Alberta. This benefits our clients who will pay less money for the survey of their developments and we can make more accurate predictions about site locations which allow them to modify their developments to avoid potential sites.

Side-Notched Projectile Point

We often post images of beautifully crafted tools such as the besant point from FcPu-11 or the siltstone knife from Buffalo Beach but not every tool we find is a “work of art.” This week’s photograph is of an “ugly” artifact we found in 2016 when undertaking an HRIA for Sundre Forest Products. The site was found on a terrace overlooking the confluence of two tributaries to the North Saskatchewan River. The artifact is a side-notched chert projectile point similar to the Prairie or Plains side-notched typology. The point is asymmetrical with one edge being a rounded convex shape and the other an undulating edge with an angular shoulder. The tip of the point is broken off which is common of the projectile points we find and is likely the reason the point was discarded. While aesthetics can add to the function of a projectile point this artifact demonstrates it was not necessary. The idea that it doesn’t matter how it looks as long as it works was alive in the past as much as it is today.

Sometimes you just can’t win!

Digging in the forest we are always encountering tree roots. It’s a great test when you miss them all. Most days your shovel is sharp enough that you hardly notice the roots as the shovel blade slices through them. Sometimes you have layers of roots, which work as a group to form a wall. You can “smash” through them with a bit of effort, one root at a time. And then there are days like pictured here! Your shovel just won’t go through or you don’t have the energy to “smash” through them, so you have to break out the big guns! I like to carry a folding saw with me in my vest, so roots like these won’t get the better of me! Unfortunately these ones did. So I just dug around them.

Introduction to CRM Part 4: Evaluating a Site

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Figure 1. Positive shovel test that contained lithic debitage.

When we identify a site, we conduct further evaluative testing to determine the type, character, and extent of the site. This is done according to government guidelines, and depends on the type of site, and the type of landform. If the landform allows for it, testing occurs in each cardinal direction or in a grid. Some sites are found on ridges or point terraces, and so in these cases, it is not possible to test in all directions (Figure 1).

Tree Time’s standards are that there must be three negative tests spaced at most 10 m apart in each direction from any positive. Sometimes additional tests are required in order to determine the significance, the size, and type of the site. For example if none of the evaluative tests were positive, further testing might be done at closer intervals to better determine the significance of the site. In addition to rigorous note taking, we also map and photograph the site (Figure 2).

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Figure 2. Vince taking notes at a site.

The evaluation of the site is an important step for two main reasons. The first is to enable the government to maintain an accurate site database and to better inform future researchers of the size and type of sites are in the area (Figure 3).

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Figure 3. We are evaluating an historic site by flagging artifacts with red flagging tape.

Secondly, in this stage we determine the extent and significance of the site. If a client decides to avoid the site, delineation allows us to more precisely buffer the site. This is important because it allows the development to occur as close to the original plan as possible while still avoiding impacts to the site. In addition, if a client chooses to mitigate their impacts to the site through excavation, a more detailed evaluation of a site allows us to better predict the productivity of the site, and to render cost estimates of any mitigation work more accurately.

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Figure 4. Buffer flagged around the site with orange flagging tape.

Once we have surveyed our targets, evaluated any sites we have found, and have finished our notes, it is time to return to the office (Figures 5 and 6).

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Figure 5. Reid is finishing his notes before we move onto another target.
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Figure 6. After a long cold day, Brittany heads back to the office.