From May 15th to 19th, I attended the 2017 National Park Service Archaeological Geoprospection Workshop held at the Pea Ridge National Military Park (the site of the largest Civil War battle west of the Mississippi River) in Pea Ridge, Arkansas. As an archaeologist whose research is focused on the northeastern United States, northwestern Arkansas was not an area I had ever envisioned conducting fieldwork. However, as I delved into the cultural resource management reports for the Delaware Water Gap National Recreation Area, where I work, I discovered that archaeological geoprospection techniques were incredibly effective at uncovering archaeological features buried below ground. At the suggestion of my advisor, Dr. Megan Kassabaum, I enrolled in the NPS workshop and flew out to northwest Arkansas to learn these techniques from the experts so that I might apply them to my own research in the future.
Archaeological geoprospection is a suite of remote sensing techniques that allow archaeologists to hopefully create a map of what exists just below the ground surface before any actual digging is performed. To do this, archaeologists measure some physical property of the soil (e.g. its electrical or magnetic conductivity or resistivity) at an archaeological site which can then be interpreted and mapped to create an idea of what may be buried below. Some popular geoprospection methods include ground penetrating radar (GPR), magnetometry, gradiometry, electrical conductivity, and electrical resistivity. Because they allow archaeologists to see below the ground before they dig, geoprospection techniques are employed by archaeologists both working in academia and the cultural resource management sector to better conserve buried cultural heritage for future generations. Geophysical instruments can also be employed to save valuable time, money, and labor in archaeological excavations (although the equipment itself is far from cheap).
I arrived at Northwest Arkansas Regional Airport from Philadelphia in the early afternoon on Sunday May 14th as the workshop started promptly at 8 am the next morning. After checking into my hotel, I decided to check out the town of Bentonville, where the hotel was located. I only mention this because staying in Bentonville allowed me to visit the Crystal Bridges Museum of American Art, which was one of the highlights of my trip. I wish I could have spent more time in Bentonville and at Crystal Bridges but the workshop took up most of my time in Arkansas.
The workshop started promptly at 8am on the morning of Monday, May 15th. All the participants and instructors for the workshop met at the Pea Ridge Library for breakfast provided to us by the town of Pea Ridge and to begin the workshop. The morning consisted of lectures introducing us to the workshop, Pea Ridge and the Battlefield, geoprospection and why archaeologists use it, and aerial techniques such as LiDAR and aerial photography. In the afternoon, we arrived at the Pea Ridge Battlefield to receive a tour of the battlefield, learn more about the site of the former Leetown village where we would be working, and to see how the geoprospection equipment we would be using throughout the week operated. Later that evening, we would return to the Pea Ridge Library to talk with the instructors about what we hoped to learn.
The rest of the week would follow a similar pattern of lectures in the morning and evening. The afternoons, however, provided us with the opportunity to test out the geophysical techniques ourselves. The data that we collected would be processed in the evening lectures to show us both how to process the data (which is far more difficult than operating the equipment) and see what our work was revealing below the surface. The data we collected would also be used later in the summer to guide the excavations of an archaeological field school at the Leetown village. Each afternoon from Tuesday to Thursday that week, I helped to collect data from the site by operating a number of different geophysical instruments including two different GPR rigs, gradiometers, and electrical conductivity and electrical resistivity meters. Unfortunately, due to the potential of tornadoes in the area later in the afternoon, I was forced to leave Arkansas earlier than anticipated and was unable to attend the last afternoon session.
Overall, the Geoprospection Workshop at the Pea Ridge National Military Park proved to be an amazing experience. I was able to learn from archaeologists employing these techniques from around the globe and I hope to be able to employ what I learned in my dissertation research in the near future.
Justin Reamer is a graduate student in the Department of Anthropology.