Saturday, October 15, 2011

Digging down through the layers: Stratigraphy at Parc Safari

Week Three for Team Danger was pretty exciting. After locating Magic's remains in a test pit during our second excavation, we arrived at the field eager to see exactly what Group B had been able to uncover. We were not disappointed.

After several minutes of bailing foul smelling water out of the elephant pit, we went to work on the task of freeing the skull from the ground. Our first goal of the day was to locate the midpoint of the cranium. After about an hour without success, we started being concerned if we would be able to remove the skull the next week if we hadn't even hit the half way mark yet! Colin was eventually able to expose it, but time was running out.

While the midpoint debacle was unfolding, other team members were hard at work expanding the pit and getting as much dirt out of there as possible. Anna and Manu expanded the pit by approximately 50cm so we could uncover the mandible and tusks. Success! As the day was coming to an end, we knew we were not even close to getting the skull ready to be removed, but we had made a considerable amount of progress. By 4:15, most of the team hit a wall of lethargy. Snack time had been scarified because of excitement, and because of time constraints. If there is one lesson to be learned, it is to never skip snack time.

As we get deeper into the excavation (pun intended,) we're starting to learn more about other methodological aspects of archaeology. For one, we're looking more closely at stratigraphy. In methodology classes, the common example of stratigraphy is a cross-section of a million years of dirt. The illistrations always show stone tools, ritual artifacts, and several storage pits intruding very clearly into another strata. Our site has none of these exciting features, but stratigraphy can come in very handy. For example, a thick, heavy clay layer that appears to be uninterupted means that we will not find any graves below it. The largest and most common strata we have found is a mixed, dark soil. This can mean that the area has been disturbed from the process of opening and closing graves. The third layer is organic trash that was buried by the zoo. There appear to have been large and small deposits of this material, which are an instant indication that there has been human activity. However, we have learned that organic trash is not an automatic indication of a grave.

Layers are more than just an indication of activity, they can tell you a lot about an area - if you're willing to listen. Roskams talks about the kinds of relationships that strata can have. For one, they can relate to their immediate neighbor and indicate changes that happened when one layer ends and the next one starts. Secondly, what he calls the "true stratigraphic relationship," is the chronological order(Roskams, 155).This can show the history of what has occurred and more importantly in what order. The final kind of relationship, is how layers correlate. A layer my have been interrupted or two layers may almost be the exact same, but are not physically connected. Looking at these connections can be informative and crucial to understanding a site. However, as Roskams notes, it can be problematic to make correlations without 100% proof they are connected.

In our excavation, we're making connections between patches of organic waste or black soil we find in a persue of graves. The organic waste may have been depositied at different times, but it has the same meaning to us whenever we find it; people dug a hole and deposited it, which mean they may have buried an animal too. Moreover, the clay layer indicates to us that we can probably stop digging there. At the back of Magic's head, a uniform clay area is becoming more exposed on the side wall. Colin has noted this could indicated the extremity of grave, but it could also just be a large clay deposit marbled into the other kinds of soil.

Furthermore, when considering stratigraphy, we need to include or exclude certain factors. In human archaeology, there is sometimes an exclusion of any non-human finds (Roskams, 180). In our case, we are doing the opposite. Mountain Dew cans, two-by-fours, and pottery shards are tossed aside to excavate the fauna!

Lastly, Roskams, highlights the importance of the "grave complex". Why was the individual buried that why and why? As we continue the excavation, we will learn more about the orientation of Magic's body and other factors, but for now we do know that h/she was in a mass grave because we have found a small scapula near the skull. Why is it there? The plot thickens, and only more excavation will tell us the answers!

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