The process of creating stone tools through lithic reduction (by removing stone chips). A hammer (such as a stone or antler) is used to strike the core rock in order to remove smaller pieces. The core is either shaped into a specific tool, like a biface, or the flakes that have been taken off are used or shaped into something specific, like a projectile point.
Surface exposures are areas where there is no vegetation and the mineral soils are visible. These can occur naturally (areas of slumping, beaches, blow-out, or other natural erosional processes), or be caused by human activity (ATV trails, furrows created for site prep and skid trails just to name a few). Surface exposures can be great for covering a lot of ground during survey.
A biface is a stone tool that has flakes removed from both sides. It can be used as a knife, scraper, or further worked into a more recognizable tool. The typical biface shape is an oval with slightly pointed ends. The biface on the left was found near Fort Vermilion in 2016.
While we always prefer to survey areas prior to any impacts, the identification of artifacts in post-impact contexts can be easier because of large areas of exposed sediments. Instead of targeted shovel tests that excavate a very small percentage of a high potential area, we can potentially see everything that is under the ground. However, the context of anything we find must be taken into account because heavy equipment can break cobbles and create things that look very similar to lithic debitage. If we find an artifact in the track of heavy machinery we need to be careful we are not misidentifying what we call a “tractorfact.”
In spring of 2017, we surveyed a proposed Associated Aggregates gravel pit that was being planned in a recently harvested cutblock . We identified several sites that were within the proposed gravel pit boundary, most of which were first identified by spotting artifacts on the ground. It’s not always easy, as vegetation can trick you into thinking you’ve found something, only to realize it was just a leaf.
If you want to try your eye, try to spot the flakes in the above picture!
How many did you find? Give up?
Keep scrolling for the answer…
It can be pretty difficult to spot because of the leaves on the ground but when you really take the time to look you can see five pieces of quartzite debitage.
A core is a larger piece of stone from which many smaller flakes are removed. These flakes are then turned into tools or are utilized as they are. There are many different types of cores, but a common way to describe them is by the direction(s) flakes were removed, or by the shape of the core. For example, unidirectional cores have flakes removed all in the same direction. That has had many stone flakes removed to make other tools.
Obsidian is commonly known as volcanic glass. It forms when a volcano erupts and the lava is cooled extremely quickly, such as when it flows into a water body. In Alberta obsidian is considered to be an “exotic material” because it does not occur here naturally. When we find it here it tells us that people in the past engaged in long distance trade, usually with people in British Columbia or the Yukon. In 2016 Teresa found this lovely obsidian flake at site FaPr-6 located near the community of Caroline.
Specializing in forestry archaeology in Alberta, I haven’t had much opportunity to work in winter conditions. One of the nice things about forestry is its relatively long planning horizon and the flexibility to schedule our work.
Unfortunately, in fall 2012, a variety of factors conspired to push some of our fieldwork into late October, and then we got an unusually early and heavy snowfall in northwestern Alberta. The heavy snow prevented the ground from freezing, so we went ahead with our planned surveys of forestry cutblocks, conducting landform evaluation and shovel testing as normal.
Trudging through 50 cm of fresh powder gave me some perspectives on moving and living in the boreal forest under winter conditions that I hadn’t previously gained. I had wondered what effect snow cover would have on mobility patterns. Summer travel in the forest tends to follow linear features like river and stream valley margins, but I’d wondered if under winter conditions that would still be the case. This week it certainly was. We were working on the Chinchaga River valley, and found that travel along the valley margin was much easier than cutting cross country or on the slopes or lower terraces. I’d say the advantage was even greater than under summer conditions. The level backcountry had deeper snow than the exposed margins, and the snow on the slopes was even deeper than that. The grey overcast sky and falling snow also obscured the sun, which made it very hard to maintain a bearing cross-country without a compass. Without a landform to follow, I could have been walking in circles and wouldn’t know until I hit my tracks.
If I was camping under those conditions, however, I think I’d be choosing very different locations than I would in the summer. The distinct valley margins, corners and points that we tend to focus our surveys on had great views of the river and were on our preferred walking paths. But they were also very exposed to the biting wind coming out of the northwest. Even the south-facing edges were exposed. The most comfortable locations we found to break for coffee were just back from the edge, sheltered in stands of immature spruce. For the last couple seasons, I’d been suspecting that our focus on exposed corners and points was only finding one class of sites, and this experience reinforces that suspicion. I think that winter camps in particular, and possibly all larger camps, would be located back from the sharp landform edges that we’re targeting most. Drainage is still a factor, especially on warm winter days when the snow turns to mush, so we should still be looking for local elevation. But maybe we should be testing some less distinct elevated landforms a little back from the edges if we want to find sites occupied during less than ideal weather.
(This brief article was originally published in the Archaeological Society of Alberta Newsletter Vol. 1, January 2013)