In the March 25th, 2011 issue of Science magazine, Michael R. Waters and associates report on the discovery of the Debra L. Friedkin site, a multicomponent archaeological site in Texas with what looks to be a buried, intact Pre-Clovis site at its base. The Friedkin site's Pre-Clovis occupation dates between 14,350-16,170 years ago (optically stimulated luminescence dates), making it one of the oldest accepted sites in the Americas (assuming it will be accepted). It is located within the floodplain of Buttermilk Creek, a small valley cut into limestone bedrock some 250 meters downstream of the famous Gault Clovis site.
But is it an intact site?
Excavation at the Debra L. Friedkin Site. Photo courtesy Michael R. Waters
Pre-Clovis in the Floodplain
Floodplain deposits are dicey to interpret, because of the way they come into existence. Essentially, terraces along creeks, streams and rivers are built up naturally during flood events. Floods, especially flashy ones, erode soil out from places higher in the streamshed and move it downstream where it's deposited in thin layers. Over time, the thin deposits can add up to substantial landforms. Most of the Friedkin site profile, down through the Early Archaic period levels, was probably laid down by natural processes; that is to say, when the flood events eroded soil, they also picked up artifacts and dropped them in the area of the Friedkin site.
Waters and his colleagues are arguing, however, that the Pre-Clovis and Paleoindian layers represent in situ occupations, that people in these groups actually did live on the creek terrace. They're basing that interpretation on the lack of artifact sorting and the presence of refits in these levels, compared to the higher levels at the site. Basically, artifacts that have been laid down by natural forces have certain characteristics: they're size-sorted. Water sorts artifacts by size and weight before dumping them out. If you're making a stone tool, you get tiny, small, medium and large-sized pieces scattered randomly in a circle around you; if that collection of artifacts is flooded, the tiny stuff floats to the top, and the heavy stuff drops out first: that's size sorting.
At the same time, fluvial deposits are random collectors, that is to say, fluvially-collected artifacts may not be associated with one another and in fact may have been eroded out of more than one site. Refits--when two pieces of a broken artifact fit together and are found close together--are evidence that the breakage occurred on site, and not elsewhere and transported in by random flooding.
- Refits are quite an interesting study in archaeology, so feel free to read more about refits
Artifacts from the Pre-Clovis Occupation at Debra L. Friedkin Site. Photo courtesy Michael R. Waters
This in situ evidence is an important argument for Waters and associates to make, because the Gault site, an enormous Clovis site (Gault is the largest Clovis site ever discovered, with over 600,000 artifacts), is located upstream from the Friedkin site, and if the artifacts were fluvially-placed, Gault could be their source. Artifacts similar to the Pre-Clovis artifacts found at Friedkin have been recovered at the Gault Clovis occupation. Gault's location upstream from Friedkin is also why Waters and his colleagues were so careful about compiling a large suite of dates, to support the integrity of the stratigraphy.
Bottom line: Is Friedkin a Pre-Clovis occupation, or the relocation of artifacts from Gault? There are no features at Friedkin, and artifacts are limited to stone tools and debitage; but the artifacts don't seem to be size-sorted, and there are refits among them. You wouldn't necessarily expect to find features or charcoal at a temporary camp suggested by the assemblage. In my opinion, the evidence is pretty strong for an in situ occupation, but clearly there are some caveats to be considered.
Waters and colleagues believe Friedkin is the latest evidence for Pre-Clovis in North America; based on the OSL dates that it certainly is. I would argue that Friedkin doesn't put the nail in the coffin for Clovis-First theories, because I suspect that theory is already dead anyway.
Sources and further Information
- The Debra L. Friedkin Site, site details
- the Gault Site details
- photo essay on the Gault site
- Pre-Clovis cultural description
- Luminescence Dating Techniques
Waters MR, Forman SL, Jennings TA, Nordt LC, Driese SG, Feinberg JM, Keene JL, Halligan J, Lindquist A, Pierson J et al. 2011. The Buttermilk Creek Complex and the Origins of Clovis at the Debra L. Friedkin Site, Texas. Science 331:1599-1603.
- Dig solidifies evidence that first Americans were here 15,000 years ago, David Brown, Washington Post
- Arrowheads Found in Texas Dial Back Arrival of Humans in America, John Noble Wilford, New York Times
- Texas find suggests earlier settlers in N. America, Randolph Schmid, AP