Archaeology Update for the Week of November 28
As the “Gobble, Gobble, Gobble!” from another completed Thanksgiving goes marching off behind us (and our belts return to their normal position!), the Headwaters excavation team got back to work after a week off for the holiday. Although it’s been two weeks since our last post, we don’t have too many excavation updates for you this week since our crew was too busy shoveling cranberry sauce and and turkey instead of dirt from test units. We’ll have more news on that front next time after we’ve had another week of digging finished up.
The Burned Rock Midden and a Bisecting
The crew did complete work bisecting, and eventually removing, the sections of the large burned rock midden inside Block D near the Well Yard. When archaeologists expose a feature like this burned rock midden, we want to see as much of it at once as we can so we will leave it in place and dig outward to find its edges (unless – as is the case with Block D – we reach the edge of our block). This gives us a good view of how big a feature is and its shape. But that only gives us information about two dimensions of a three-dimensional feature. By removing half of the feature and leaving the other half in place (aka “bisecting”) we can see it from the side. We can see if a feature is flat like a hearth or basin-shaped like a roasting pit. We can see if soil stain is just a thin smear or if it’s a deep, organic-rich storage pit. We probably stand to learn more about a feature by bisecting it than by just exposing it from above (or at least just as much). Archaeologists scraping off a layer of soil beneath the burned rock midden. As we’ve discussed in our video feeds and on previous updates here, because of the “Law of Superposition” we know that these soils are most likely older than the midden itself and any artifacts that are recovered from these soils came from people who lived here before the midden was formed.Here’s another view of the midden being bisected. You will note that this feature looks to be only a couple layers of rocks thick. Some burned rock middens can be several feet thick!
The Burned Rock Collection Quandary
We’ve been asked a couple times recently, “What happens to all of those rocks from features like that after they’ve been removed?” While archaeologists collect a LOT of artifacts during excavations like these, more often than not, burned rocks like those seen in the pictures above and discussed in last week’s live update are not collected. We do count them all and weigh them to get an idea of the rock density within a given level and we collect some basic information about sizes encountered but beyond that, these rocks typically are discarded after they’ve been recorded. Some argue (including among us professional and academic archaeologists, actually) that we can learn a lot from these rocks (such as food preparation techniques and food choices) and we should save all of them for future research. In some projects we do save them for that purpose. The difficult reality is that as much as we would like to save everything for future researchers, those rocks take up a LOT of space, and that space costs a lot of precious money to store for future analysis. When you add in the costs that would come from having someone clean and label and tabulate every one of those rocks, for now at least, the long-term cost-benefit indicates that saving burned rocks is limited to dedicated, special studies.
Yum! Pemmican! The first of three evening/weekend themed tours was a success!
In other news: we did host the first of our three themed tours out at the Headwaters site on Thursday evening, November 15th. We had a great time talking about food with AmaTerra Environmental, Inc.’s senior archaeologist (and resident foodie) Rachel Feit. Event attendees learned about feasting and food preparation in ancient Texas and got to watch Rachel prepare pemmican, a Native-American staple across North America that consists of ground-up (pretty-much powdered) dried meat, dried fruit/berries, nuts, and animal fat that was prized for providing valuable calories and energy while resisting spoiling. We all got to try a sample and ya’ know what? It was actually quite tasty! Here’s a link to a site that gives you some pemmican recipes if you’re interested in giving it a try. I promise! It was very good!It isn’t often that an archaeology presentation includes flame! Rachel’s camp stove melted duck fat for her homemade Pemmican.Check out Rachel’s presentation below!
It’s Time to Splash a Little
For those fans of water screening out there (and you know who you are!) hang on to your hats… the sump and pump systems are up and running! Near the center of the Headwaters site, in an area that’s been shown to be damaged by previously disturbance, the crew dug a pit, lined it with plastic, and filled it with rainwater then lowered some pumps in and connected them to garden hoses. Starting later this week, our crews will begin excavating a 50 x 50 centimeter test unit off the edge of the larger excavation blocks and screen that soil through a finer mesh (twice as fine, actually) than our standard 1/4-inch screens.
So… why are we doing that and what does this have to do with water pumps?
Quarter-inch screens are essentially the standard size for most archaeological excavation and survey work in this part of the country. They occupy that sweet spot of catching most of the artifacts while being big enough to get the dirt through as quickly and easily as possible. A coarser (aka bigger) mesh would get the dirt through more easily, but you’d miss a lot more artifacts. A finer mesh catches more stuff but is a lot tougher to screen through, resulting in a slower excavation process (which is more expensive). So for almost all of the excavation work we are doing here at the Headwaters, we are using the standard mesh.
Smaller artifacts can still be useful, though. We are going to be screening a small sample of the site deposits using a finer mesh to look at those smaller artifacts (particularly tiny fragments of chert rock produced when people chip stones to make tools) because they can tell us just how solid and intact these apparent ancient living surfaces actually are at this site because small objects tend to move around more easily in the soil than big ones.
Since we still have a schedule to keep, water is going to provide that soil with some much-needed convincing to get through those screens.
Flintknapping with TxDOT’s Chris Ringstaff on this Week’s YouTube Live Video
Finally, speaking of chipping stones to make tools. This week’s live video (scheduled for Thursday, 11/29 at 10 AM (CST)!) features flintknapping with our special guest, Chris Ringstaff, a staff archaeologist with the Texas Department of Transportation’s Environmental Affairs Division. Chris is a great guy, well known in the archaeology community for his skills at turning a rock into a sharp, functional tool using techniques that are literally millions of years old.
It should be a lot of fun! Really… if you were hoping to have an archaeology video that included blood, this one’s gonna be your best shot!
Please visit our YouTube page to subscribe to our channel and watch us live! Do you have any questions for us? Ask us in the chat window. We got word that a preschool class in Indiana was watching us last week! Hi kiddoes!
Until next week!