Shovel Test Pit Stratigraphy
We are all familiar with setting up a test dig. Lots and lots of post holes and weighting and counting artifacts and establishing minimum vessel counts. But on my first test dig site I noticed something interesting. We were doing a lot of digging but there was no way to see the stratigraphy of the ground below us…until…An idea occurred to me. What if I could figure out a way to see the sides of the hole.
Fig. 1 shows a typical wall shot in a pit.
Fig. 2 is a high resolution photo mosaic of the same wall used as a teaching tool. This image was constructed from 18 scaled 14.4 MP photos. (The resolution, approximately 200 MP, is greatly reduced for the website.)
Fig. 2 Excavation in Detroit’s Corktown, back of a Workers Row House, c Mid 19th Century
Fig. 3 is a high resolution photo mosaic of a post hole test pit. Notice the inset hole-shot photo in Fig. 3. This is often all you would see of a 30 to 40 cm diameter test pit. However the main image is a scaled high resolution composite of the inside of the hole. Fig. 4 & 5 are additional examples. Camera: Canon Powershot G10, 14.4 MP. (This is my down-in-the-dirt camera.)
Fig. 3 Illustrates the difference between a stratigraphy shot composite and a simple shovel test pit (inset).
The following figures illustrate how to take post hole shots for stratigraphy.
Fig. 6 Monopod Setup
Fig. 7 First Photo Level
Fig. 8 Second Photo Level
Fig. 9 Third Photo Level
Fig. 10 Fourth Photo Level
Fig. 11 Fifth Photo Level
(Leaping tarantula added for my good friends Brenna and Sam whose first encounters with tarantula will never be forgotten!)