Jonathan Alperstein, Vassar College
(June 29, 2016)—Whether you are working in a pit house or a pueblo room block, one of the most exciting parts of an excavation unit to work on is the floor fill. This year, while excavating the pueblo room we labeled Feature 300, we removed a grueling number of buckets of nearly artifact-free fill, with only the hope of a beautiful adobe wall in the southern part of the unit to keep us sane.
Although the early discovery of a rusted nail in our excavation unit (which looked uncomfortably like the nails we use to mark our excavation boundaries) and the extremely low density of artifacts in our fill seemed at first to enforce our disillusionment, things slowly began to look up when we uncovered a bone awl. This was the first sign that we had begun to uncover more artifact-rich floor fill in our excavation unit, getting closer to our first floor.
It is fairly common for pueblo rooms have multiple floors. This occurs when residents of these rooms remodel the floor multiple times, placing new floors over older ones. Each new floor surface allows us to understand the people living within these rooms. Floors are extremely important to archaeologists for context: they are not just fun to find, but also provide important architectural information, and often have interesting artifacts resting on top of them.
In our feature, floor fill was not a natural level that occurred within the soil, but an arbitrary level of 5- 10 centimeters of soil above the floor. We excavated in this way because it is most likely that many objects in the floor fill level were purposefully left behind before people moved on. Artifacts found directly on the floor are mapped and bagged separately from other items. All other levels, while important, could contain later mixed deposits or other deposits with a less-precisely-understood context than floor fill and floor artifacts carry.
In Feature 300, we uncovered a room floor, which is best preserved near our southern adobe wall. The floor continued throughout the excavated part of the room, but was disturbed throughout from rodent activity and other perturbations.
One of the hardest parts about finding floors and other architectural features is distinguishing them from adobe melt. When our team began to excavate, we quickly ran into a compacted layer that was made of up of adobe melt, a hard material that often resembles a floor. Adobe melt is created from eroding architecture as adobe from the walls melts and re-hardens. Although there was a relatively low density of artifacts in this adobe room, the artifacts we did recover included faunal (animal) remains, pottery sherds, lithics (stone tools and tool-manufacturing debris), shell, and ground stone.
Originally, we thought the room contained mostly undecorated plain or utility ware, with only a few pieces of Salado polychrome pottery. While washing artifacts, however, we quickly realized that some of the dirt-encrusted sherds we originally thought were plain ware were actually El Paso Polychrome. One of the most exciting finds in our floor fill was a few fish vertebrae, a relatively rare discovery in our study area.
The artifacts we found directly on the surface of the floor included a few pottery sherds, a piece of worked obsidian (volcanic glass), an animal bone fragment, and an unfinished stone biface (a stone tool flaked on both sides). Finding the biface was unexpected because it is a much older style that predates the use of our excavated room in the 1300s. This biface has a basal thinning flake taken out of one side. Why was this unfinished biface left on the floor of a much later room? Leaving an Archaic-style point in a room is often thought to be related to a closing ceremony. Finding older points (or darts) in sites is not uncommon, and is seen in kivas as well as residential rooms.
Some of the important features found on floors include pits, post holes, and hearths. Pits can be created for storage, although pits are also sometimes caused by rodents or other animals. Post holes can be important for dating the site, if there is a charred remnant of the post still in the hole. Hearths are where there would have been a fire in the room.
The depth of the floor is also critical to understanding the room’s architecture. For example, in Feature 300, the southern adobe room wall contains a line of four horizontal holes. We can assume they were made by people because of their straight alignment and even spacing. Because our room floor is less than a meter below these holes, we can infer that they were not used for roof support, but had another use—possibly for a shelf or other room furniture. Alternatively, they may belong with a lower floor we have not yet excavated.
Unfortunately, the importance of floors is not just known by archaeologists but also by pot hunters, who will dig to and through the floor in order to find a complete pot. This undocumented digging is unfortunate, because the contexts of artifacts on floors are critical to understanding why and how rooms are abandoned. Floor fill and the artifacts found floor surfaces allow us to answer important research questions about the relationship between people in the past and their artifacts and architecture.