Magnolia Valley Field School: Week 5 Recap

— post by Dr. Peres

We have just finished Week 5 of the MTSU Field School at Magnolia Valley. This means only TWO WEEKS left before we close the site.

Monday was a complete wash and we spent the day in the lab washing, sorting, and bagging artifacts for analysis later this summer.

We were able to start our Tuesday at the field site and get in a few hours of work before the rain rolled in and we had to close up the site for the day. Just as we finished closing up the site and were preparing to head back to campus, we noticed the field school van had a punctured tire and was quickly going flat. Luckily, Field Assistant Joey K., was able to change the tire so we could get it back to motor pool and get a “fresh” van.  The rest of the day was spent in the MTSU Archaeology Teaching Lab. Jesse gave a mini-lecture on lithic analysis and I gave a talk on how to prepare a Curriculum Vitae (CV) — basically a long resume that details one’s education, work experience, research, publications, etc.

Field Assistant Joey Keasler changes the flat tire on the field school van (with help from the students). Thanks guys!

Field Assistant Joey Keasler changes the flat tire on the field school van (with help from the students). Thanks guys!

Artifact washing in the MTSU Archaeology Lab (Nathan Allison in the foreground, Josh Bicknell in the background; hands belong to various students who wish to remain anonymous).

Artifact washing in the MTSU Archaeology Lab (Nathan Allison in the foreground, Josh Bicknell in the background; hands belong to various students who wish to remain anonymous).

 

Finally, Wednesday morning arrived, sunny and mild. Everyone was ready to be on-site and move more dirt! We are all in the groove of the daily morning routine of uncovering the units and setting up the equipment in the mornings, schnitting, troweling, filling out paperwork, and screening for artifacts. Everyone knows what an artifact is — any object made, modified, or used by humans.

Obvious artifact: stemmed spear point made from chert.

Obvious artifact: stemmed spear point made from chert.

 

This week we introduced the students to the art form of feature identification. A feature is a non-moveable area that indicates human activity — such as a hearth, building wall trench, or storage pit.  Features are some of the most important things we identify in the field and why we excavate in a controlled scientific manner. Identifying features is a bit of an art form  and involves a lot of standing back and studying the soils exposed in the excavation units to determine changes in colors/textures/inclusions. Sometimes these changes are flick-you-on-the-forehead-obvious; other times it takes the trained eye of a seasoned archaeologist to tease them out.

Jessica O. trowels the floor of this unit to expose Feature 6.

Jessica O. trowels the floor of this unit to expose Feature 6. The unit directly to the west (the right in the photo) will be opened next to capture more of the feature. 

Can you spy the feature (Feature 4) in this color photo? (Scroll down to the next picture to see the unit in black & white.)

Feature 4, color photo (not an official photo for curation purposes).

Feature 4, color photo (not an official photo for curation purposes).

 

Same unit, only with a black and white filter applied (again – photo is for illustrative purposes, NOT an official curatorial photo). NOW do you see the feature? (Hint: it is dark soil on the lower 1/2 of the unit).

 

Feature 4, black and white filter applied.

Feature 4, black and white filter applied.

 

So far we have identified 5 cultural features (meaning ones created by humans) and one non-cultural feature (meaning likely remnants of where a tree or root once were). The five cultural features are in areas that we targeted specifically due to the remote sensing data Tim DeSmet generated early in the project. Over the next two weeks we will continue to expose these features by opening up adjacent units. We will then document them (by mapping the plan view and photographs) before excavating them. More on that in a later post.

 

Looking to see who visited us this week? Check out our Facebook page and Flickr account for photos!

 

 

The importance of the hypotenuse

— post by Jesse Tune, Project Co-Director

 

Today is the day that many people have been waiting on – the start of actual excavations! The students were split into two crews: one crew of students worked on finishing up shovel tests in Area I, while the other crew headed back to Area A to setup the excavation grid and begin excavations.

The preliminary results of the geophysical survey in allow us to make an informed decision about exactly where in Area A we want to excavate. As a result, we need to carefully lay out the excavation grid exactly the same as the grid used for the geophysical survey. We also must take extra care to ensure that each 2 meter x 2 meter (6.56 ft. x 6.56 ft.) unit within the grid is a perfect square. It is important that each unit is exactly 2 meters x 2 meters so we can precisely document where every artifact and evidence of human activity is located. This process consists of using several long reel-tapes, countless pin flags, a bit of patience, and a little basic trigonometry.

We start by using two tape measures to establish a south and east baseline. Two additional tape measures are then used to mark the west and north lines of the grid and create an 18 meter x 32 meter (59 ft. x 105 ft.) rectangle. However, simply because opposite sides of the rectangle are the same length does not mean that the excavation grid is set up with 2 x 2 meter square units. A diamond has opposite sides of equal length, but they do not meet in 90 degree corners; thus, not squared. This is where a little trigonometry comes in handy. Thanks to Pythagoras of Samos, we can quickly and easily determine if the corners of our grid are 90 degree angles, and thus if our grid is set up correctly.

Grid 1

The only time they are allowed to sit while working! Field school students (L to R: Nathan, Susan, Kelsey) hold down reel tapes and prepare pin flags for the excavation grid.

 

The Pythagorean Theorem says that A2 + B2 = C2, or essentially that if we add the square roots of two sides of a right triangle together, it will equal the square root of the hypotenuse. So we know that the distance between two opposite corners of our 18×32 meter grid should be exactly 36.715 meters.  By using Pythagoras’s simple equation to ensure that our grid is perfectly squared.

A perfectly square 2 meter x 2 meter unit. The orange pin flags mark the corners, the pink string outlines what will be the outside walls of this unit.

A perfectly square 2 meter x 2 meter unit. The orange pin flags mark the corners, the pink string outlines what will be the outside walls of this unit.

We are off to a great start to excavations and already have four 2 m x 2 m units down 10 centimeters (cm) (approx. 4 inches ) or more in depth. We should have at least a total of seven units in active excavation by Friday.

Three of the four 2 meter x 2 meter units in active excavation.

Three of the four 2 meter x 2 meter units in active excavation.