Clay Pots and Porcelain

This week, Team Paleo finished up one project and assisted with another. 

The team has been working on sorting, photographing, and organizing the museum type collection for many months. During the last two weeks, they organized a large collection of lithic points and other objects donated by another local museum. Each piece needed to find a home in the large type collection. 

Later in the day, Team Paleo got to offer a small help to a large project. Dickson Mounds has been adding an exhibition of Illinois life in the early 1800's, so the team got to unpack some of the artifacts that will be displayed. Instead of stone arrow points and earthen clay jars, the collection included steel knives and blue porcelain transferware. 

Sorting lithic points by type and placing them in large wooden drawers for the type collection.

A tiny number of the large lithic point collection to be sorted.

There is always time for some jokes and laughter in the collections room...

Our fearless leader, Dr. Michael Wiant, ponders lithic types.

The Illinois in the 1800's collection- Carefully boxed up and ready to be displayed in the new exhibit.

Early 1800's artifacts. Containers evolve from clay pots to glass and porcelain.

Team Paleo volunteer, Ronan, unpacks a box of interesting artifacts.

Last Dig Day

Often archaeologists discover most of their finds toward the end of the dig. It's a bit of a frustrating conundrum! On Gwen's last dig day, she took lots of pictures of a house the MSU team was excavating.

In a smaller pit feature, we found exposed bone, likely from a meal of a larger bird like the geese and ducks that still inhabit the nearby Emiquon Nature Preserve. Bones and scraps like this are tossed into a garbage pit where we find them today. Obviously, it is helpful to know what the people are eating, but quantity of materials also helps us know how many people may have been living there. For example, if we find large quantities of deer bones we know deer were abundant at that time. We might go further and see if they are using the bones to make tools, like needles, awls, hoes from deer mandibles and scapulae.
We also see a reddish chunk of sandstone in the lower right hand corner of the image. It was exposed to fire at one point, as the sandstone is red. 

The morning weather was unsettled and scattered showers kept hitting the site. But the clouds cleared quickly and by ten in the morning, we were enjoying sunny weather. We can continue to dig during a light rain, with the use or tarps and tents (which also keep the glaring sun off of us on hot days). But we have to 'tarp up' the dig site in heavy rain. This means we must cover every inch of the excavated area with a large tarp, using sandbags to try to seal and secure the edges. Nevertheless, rain water will still percolate into the excavation. It is, after all, a big hole in the ground. Sometimes pumps must be used to siphon the excess ground water out of the excavated areas. 

At the house, we see a cross section or profile of the excavation. Charred logs are easy to see- possibly a sign that the house building burned in a fire. Already removed from this section were 3 or 4 other charred logs. 

This is a closeup of the image above, where we saw evidence of charred logs. You can see that the soil here is yellow and lighter in color than the surrounding soil. The lighter soil is the natural floor of the house when the original residents lived there. In other words, it is ground level. All the darker dirt on top is from the plow zone or A horizon fill- this is soil, organic material, artifacts, and naturally accumulating materials that fill in where the house used to be.
Usually, these homes were built by digging a basin into the earth, then building short walls around the edges. Imagine the classic 'sunken living room' in a modern house- except the entire house is sunken. 

Here you see a large pit feature in the earliest stages of excavation. Across the approximate center is a string, which marks the diameter of the circular shape of the feature. The string provides a straight line, making it easier to know where to dig. You start by digging on one side of the string giving us a clean profile wall along the string. 

This is the same pit feature as above, but digging has commenced. Digging occurs in 10 centimeter deep increments, creating levels that are clean scraped, mapped, and photographed for documentation. The reason for going down 10 centimeters at a time is so you can see the pit feature as it progresses down. This also saves the excavators and screeners from processing clay-like b-horizon soil that is not part of the feature.

Same feature, clean scraped and ready for photography- You can faintly see the edge of the feature where the darker soil meets a lighter, yellow soil, near the upper left hand side of the photograph. So where we see this soil demarcation, the edge of the pit feature is established. 

Here is another example of bisection lines. This feature has not been excavated at the time of the photograph. 

One of the MSU students excavated this feature- a post mold with the remains of the charred post still visible. You can see the bisected profile wall clearly here. Once the feature has been photographed, the charcoal is carefully removed and wrapped in tin foil to protect the friable material. Samples are sent to the lab for analysis of the type of wood used. It could also be dated for age. 

A large fragment of decorated pottery- I found this in the pit pictured above. 

This is an exciting find- burned roofing thatch that had fallen into the pit feature we were digging. Likely to be made from grasses, thatching was used for covering the roof of a structure- probably a home. Preservation in this pit is good, as charcoal often degrades easily. 

Here we see the pit feature containing the charred roofing thatch. We can also see the straight bisection line dividing the pit in half, as well as the excavation boundaries. Each level is 10 centimeters deep, and like stairsteps. Of course, the pit would not have originally been dug in stairsteps- this is a result of careful excavation which shows the borders of the pit at each 10 centimeter level. 

A photo showing the entire excavation block in which we worked. Our pit with the charred thatch is in the center of the image. In the upper left hand side is another large pit feature- you can see that the walls are almost straight down, rather than stepped. This is because the pit is deep and cylindrical in shape, where as the charred thatch pit is more shallow and the walls are bowl shaped. However, later in the dig we discovered that what we thought was a shallow bowl ended up being a six foot deep storage pit.

Gwen at the dig. 

One large block and a screening shade to the right.

The Michigan State University students and teachers along with Dickson Mounds Museum staff

Hidden Treasure

Gwen snapped a few cell phone pics last week during the dig. While clean scraping a house basin she uncovered three (of many) artifacts. 

Decorated pottery sherd. Punctated along the top, with incised curvilinear lines. Likely Mississippian.

Madison point with evidence of heat treatment

An undecorated rim sherd, likely Mississippian. 

Here is an interesting page that describes pottery decoration in Woodland and Mississippian pottery: 

http://www.beloit.edu/logan_online/exhibitions/virtual_exhibitions/north_america/woodland/techniques.php

Excavation Finds at Morton Village

This week brought some interesting finds at the Morton Village dig site near Lewistown, Illinois....

An unusually large pit feature measuring over four feet deep. It may have been a storage pit that was emptied at one point and refilled with garbage. The depth is typical of storage pits.

At the top of the picture you notice the hole is straight and flat like a wall. This is how the profile (center slice) of the pit feature is exposed. If you look in a profile, you can see the shape and border of the pit, making it easier to excavate the other half of the pit. Some pits have post molds or other pits dug into the same area. Profiles help distinguish these different overlapping features.

In this image it is easy to see the layers and different colors of earth. On the profile wall, you can see 'layers' of different colored dirt. This is likely because the people who used it as a garbage pit would place a layer of garbage down, then 'cap' it with a layer of dirt. This continues until the pit is full. This dig showed evidence of capping, and because the soil content was acidic here, much organic material breaks down. We don't see evidence of the organic remains as whole artifacts. We did, however, find a chunk of red ochre (or possibly hematite) and a huge limestone rock.

Also of note is the whitish colored earth at the bottom of the pit, located in the upper left-hand corner of the excavated hole. On the left side, midway down the hole, a scoop is removed from the wall. This is where several pottery sherds were found, likely from an Oneota pot. 

It might be hard to see, but along the middle of the image are two darker colored streaks going from bottom to top. They look a bit like tire tracks from a vehicle. However they are evidence of wall trenches that form a large circular structure. Here is only a few feet of the wall trenches. When we say LARGE structure, we are talking 40 to 60 feet in diameter!

Wall trenches result when people dig into the soil a certain depth, then place upright logs in the trench to make a palisade-like wall. Think privacy fence made of whole logs. What we see is the discolored stain of either the organic remains of the posts or fill dirt that drifted in after the wall trench was emptied. Some of the graduate students working on the dig mused that this great circle may have been open at the top- no roof.  The trench walls are concentric- one wall within another wall not because there was a double wall, but because one feature may have been constructed first, while a second was constructed to replace or enlarge the first feature.

Around the edges of this image you can see several post mold excavations. 

Here we see an exceptionally dark post mold discoloration, easily defined by the dark blackish soil. You can also see the circular shape. Of course, it could also be the remains of a tree root. Excavation will provide more information. The first post mold Gwen excavated was about 9 inches deep. Some run 2 to 3 feet deep. 

Commentary provided by Gwen McDaniel

Katie Joins the Dig

Katie wrote up a letter of her credentials this spring in hopes of assisting with the summer dig hosted by Dickson Mounds and Michigan State University. Accepted in, she's been working hard this summer.

Screening for artifacts- this technique allows the discovery of artifacts too small to notice while skimming the earth layers, but larger than 1/4 inch in size. This means many small pot sherds, chert flakes, bits of charcoal from fires, clay blobs, and bits of bone.

Pausing for a photo on this hot afternoon. Behind is the shade canopy covering the spot where Katie and Gwen are digging.

All artifacts from this pit feature go into the bag. Later on, they are washed, sorted, and cataloged. Junior volunteers Ronan and Hannah joined in for an hour this day.

The pit feature that Team Paleo has been helping with. They are working with a graduate student from Michigan State University, and learning to differentiate the colors, textures, and subtleties of soil within a feature. This hole goes down about 2 or so feet. 

Gwen Digs a Hole

Gwen decided she'd like to try her hand at a real dig this year. She sent in a letter to Dickson Mounds with her qualifications and interests and was accepted as a volunteer. Each day starts early and ends late with a little sunburn and a lot of fatigue. But Gwen is having the time of her life! The dig is hosted by Dickson Mounds Museum and Michigan State University.

Screening dirt to isolate small artifacts such as chert flakes, pottery sherds, pebbles, and charcoal. 

Gwen's first post mold excavation! 

The screening station 

The excavation 'block' with a tarp over half of it to prevent the dirt from drying out. Each block is 4 meters by 4 meters. This block contains a post mold and another pit feature... so far!

Cleaning the equipment is important! Rusty tools don't work well.

We use wire brushes to clean off the dirt, and files to sharpen the shovels and trowels. 

Searching for Artifacts at the Ogden-Fettie Site

After a wonderful afternoon working with the crew at Dickson Mounds Museum, Team Paleo hit the local ice cream joint in Havana, Illinois. The Team savored some single scoops while we chatted about the day's work.

Three beautiful oaks crown the ancient mound at the Ogden-Fettie site

So, you went out to the Ogden-Fettie site today...

Katie: Yes, we combed the fields looking for artifacts.

Gwen: And gathered artifacts from certain grids so we could map out how densely packed the artifacts were in the area. As well as what major types of artifacts are in each location. The other kids found lots of pottery but we found mostly chert flakes and sandstone.

Katie: And we found a really small pink colored arrow point.

Gwen: I think I found the end of a drill. It was the right width and had chip marks on either side.

How did you find these artifacts?

Katie: We walked in rows looking for any artifacts sticking out of the ground. Any little flakes from the arrow points and bits of pottery... some things just stand out against the dirt and soil in the field.

Under the shadow of a Native American mound, the gals from Team Paleo scan a recently tilled field for artifacts.

So you were searching in a plowed farm field?

Gwen: Yes. The Ogden-Fettie site lies in what is now a farm field. There is a large mound in the center of field- I'm not sure if it was a platform mound for a building or burial mound. The mound is kind of square or rectangular shaped like the one at Cahokia, but this is not as big.

Katie: But we were searching near the mound, below it. It was really interesting being able to just look down and see an arrow point! When I found a raccoon skull, initially I just saw a few teeth, but by digging around I uncovered the whole thing.

To search for artifacts, each person (or team of people) tackles a 30 X 30 meter square. We simply walk up and down the square, covering a 3 foot swatch at each pass. After about 10 laps the square is covered. Depending on the density of artifacts, a square could take 20 minutes to an hour to search through.

What goes through your mind when you pick up an artifact?

Katie: It's interesting that Native Americans have touched these things and we are here hundreds of years later, touching the things that no one has seen in centuries.

Gwen: I'm always surprised that the artifacts are still there. I see something and know it is a chert flake, but others might just think it is a rock. One thing that I do is I try to imagine what it was like when there were houses here- or a settlement. Dr. Mike says there might be pit features there because we found areas dense with pottery sherds and chert flakes.

Katie: I love being able to work on uncovering all these artifacts. Ancient people LIVED here, worked here, spent their whole lives here- How interesting to work in the same place others did hundreds of years ago.

Team Paleo and Dr. Mike

Using the Total Station Transit To Prepare the Excavation Site

Last Friday Team Paleo found themselves working in the field at a local dig site, known as the Morton Village Site, to prepare for students from Michigan State University to excavate in a few weeks. When we arrived at the archaeological site, Dr. Conner, the person in charge of the dig, handed us a satellite map with a grid, and a long pole with a mirror on top. He showed us a rectangular box sitting atop of a tripod. The box was a device called a Total Station Theodolite. When we aimed the reflector pole at it, the Total Station would bounce a laser off of the mirror. The machine measured the time it took for the laser to return, and used trigonometry to figure how far away the reflector was.

We would be using the reflector to measure out 30 meter (98 feet) squares for magnetic surveying. After trekking approximately 30 meters through knee-deep grass, the team received information from Dr. Conner over a small radio, telling us how far we needed to move to get to the right spot. Finding the exact location to place a stake usually went something like this: * Static * “...Move it 1.6 meters towards me...”  * Static * “...6 inches to your left...” * More static * “...That looks good... Move it right 4 inches...” * Static * “...Go south 15 meters...” We would move back 15 meters and repeat the process all over again.

Several hours passed, and finally our work was complete. We returned with the reflector, where Dr. Conner informed us that in the next few weeks, the folks in charge of the survey would arrive with a magnetometer and scan the squares we laid out. A magnetometer scans the ground to detect minor differences in the magnetic properties of the soil. Dr. Conner invited us back to help with the survey. We all agreed, and are eager to try our luck with another expensive machine.

Total Station Transit

Reflector

More Information on the Total Station Transit 

A Total Station, which we used to determine the location of our dig site, is designed to measure the distance and angle between itself and another point. It starts by sending an electric laser to a reflector. When the beam returns from the reflector, the transit measures the return time and uses trigonometry to calculate the distance from the reflector. A grid, established in the 1980s at the Morton excavation site, allows us to pinpoint the coordinates of the point we want to find. Using the original grid as a starting point, a handheld computer calculates the coordinates so that we don't have to figure it in our heads.

We used a GIS, or Geographic Information System, to map information about the site. The GIS also stores coordinates for past excavations, allowing us to refer to them. Team Paleo identified new excavation areas we wanted to survey and then we placed the coordinates of the 30 x 30 meter blocks into the GIS. Then the information was transferred to the handheld computer. The computer signals the Total Station transit to find the first set of coordinates, and the transit calculates the angle and distance of the location. When the person manning the transit aims it in the given direction, the person in the field with the reflector lines up with the transit. They move back and forth until they find the coordinates indicated. In the last satisfying moment, an indicator stake is placed at the final coordinate.

Articles written by Gwen McDaniel

Preparing For Dickson Mound Summer Dig

Today, Team Paleo tried their hand at something new. Using surveying equipment, the Team and the experienced archaeologists at Dickson Mounds marked off a potential dig site. First the area is measured out and marked with orange stakes every 30 meters. Later on, remote sensing equipment will be used to determine if there is anything good down there to dig up. More on that in a few days...

Finding the right spot

Driving in the stake and marking the measurements

Dr. Conner explaining the plan to Team Paleo