scraping soil, features revealed
ears bless the silence
Our archaeologist is back in the field this week. She’s gone over the results of her controlled surface collection and decided where to place her initial excavations. In the US, the work I’ll describe here is usually called a Phase II investigation. Phase I is the survey that came before.
I’ll bet a lot of you envision something like this if you ever give thought to archaeology.
And the backdrop might look like this.
Some folks do work in such places. And sometimes we do resort to small brushes and hand-crafted chopstick tools for delicate artifacts and skeletons.
But a lot of archaeology is done today in advance of construction projects. It’s often required by various state and federal historic preservation laws. And we don’t have the luxury of spending years at a site, or even an entire summer. We have to get the work done on tight schedules. If you visit our poetically minded archaeologist in the field, you’ll probably see something like this.
Yep, heavy equipment. We use it a lot in open areas such as agricultural fields. When an area has been plowed for years, the upper part of the soil has been repeatedly mixed and churned. Any artifacts within that “plow zone” have been moved from where they were originally dropped. We can make some basic interpretations with these artifacts, but nothing really in-depth (so to speak).
But the soils beyond the plow’s reach are intact. And we can learn a lot more about the people who occupied a site with artifacts and features from those depths. Features are the remnants of things such as hearths and houses and other buildings that have preserved in or on the ground. They can be stone foundations or the rotted remains of wood posts. With these, we can pinpoint where people were living, get an idea what their houses looked like, and see where they did their cooking or made their stone tools and pottery. Sometimes features are obvious above ground. Pyramids are features. The collapsed remains of an 1800s house and barns in a farm field are features.
When you’re on a tight schedule and have 30 centimeters (1 foot) or more of disturbed soils to go through, you will use heavy machinery if you can. It’s often the most efficient and cost-effective way to “open up” enough of the site to see if features have, indeed, preserved. Archaeologists will have the backhoe dig a series of “exploratory trenches” to search for these features. If there are no features, your work is probably done. But I think our archaeologist still has some work ahead of her.
Archaeologists are trained to recognize differences in soil colors and textures. Features that were dug into soil usually look different from the surrounding soil for various reasons. For example, organic material or the heat from cooking fires will change the soil color and texture. Usually, the features are darker than the surrounding soil, as you can see in the photo below.
In this week’s poem, the backhoe has revealed a change in soil color in one of the exploratory trenches. We wouldn’t yet see the profile that I show above. Instead, our archaeologist would see a dark circle on the ground.
Since she hates loud noises and the smell of diesel, she’s happy to tell the operator to shut down for now. If she still needs him to dig more trenches, she’ll have her crew chief monitor the work, hopefully far enough away to keep her from getting a headache. But for now, she’ll switch to some smaller tools to investigate this feature more carefully.
I wonder what she’ll find….