12,000 Years Ago on the Copper River
Overview of project area and site locales. Originally published in: Reininghaus, Lee. (2019). Recent Archaeological Investigations of Glacial Lake Atna Shorelines in Wrangell-St. Elias National Park and Preserve. National Park Service, Wrangell–St. Elias National Park and Preserve, Copper Center, Alaska, 99573.
Archaeologists Lee Reininghaus and John White have successfully documented people’s use of an area near the upper Copper River over 12,000 years ago. This is many thousands of years earlier than previously documented sites in the Copper Valley. For context, the earliest dated sites found anywhere in Alaska are estimated to be 14,500 years old. These are in the Tanana River Valley.
Reininghaus and White discussed their work in two fascinating public virtual presentations last month. The talks were part of the WISE Virtual Science Lecture series, and are currently available for viewing online at WISE-edu. Reininghaus is an archaeologist for the National Park Service in Wrangell-St. Elias National Park and White is a PhD student at the Center for the Study of the First Americans, within the Anthropology Department at Texas A & M University.
Both Reininghaus and White began their talks by speaking about Ahtna, Inc’s partnership. “First and foremost I need to thank Ahtna, Inc for allowing us to do this research,” said Reininghaus, “The shorelines of Lake Atna didn’t follow any modern land boundaries and they’re located throughout the entire Copper River Basin. Most of the areas we investigated and the sites we identified are actually located on Ahtna [Inc] lands. All of the artifacts that we found represent their deep tradition of connection to the landscape. All of those items and that knowledge belongs to the community so we’re privileged and grateful to be able to conduct this research, learn more about these connections, and share all of that stuff with you.”
Reininghaus credits Ahtna, Inc for their collaboration in sharing traditional knowledge of historic travel through the area. This knowledge was essential to help identify candidate sites within the huge expanse of the Copper Valley for excavation.
White also expressed gratitude for Ahtna, Inc’s collaboration and dialogue throughout his involvement in this project. He added, “This is not my heritage that I'm trying to help understand and present. I really do appreciate being allowed and having the honor and the privilege to help understand and expand on this amazing story.”
White spoke about his particular interest in the Copper Valley area not just in terms of the history of this specific area, but as a part of the larger story of how people first populated all of Alaska and North America. There are multiple theories about how people populated North America, which are not mutually exclusive. Could very old sites in the Copper Valley provide any additional clues?
Artifacts from the Windy Ridge archaeological site, illustrated by Lee Reininghaus. Originally published in: Reininghaus, Lee. (2019). Recent Archaeological Investigations of Glacial Lake Atna Shorelines in Wrangell-St. Elias National Park and Preserve. National Park Service, Wrangell–St. Elias National Park and Preserve, Copper Center, Alaska, 99573.
As discussed in our February 4 edition, archaeologists have long suspected that people were in the Copper Valley long before previous documentation suggested. One tantalizing clue to this was obsidian tools found at very old sites in other parts of North America with obsidian sourced from Wiki Peak in the Wrangells. However, the oldest sites that had been dated from the Copper Valley area were from just about 3,000 years ago.
To begin searching for older sites, Reininghaus collaborated with a team of people from several disciplines to identify areas that might have been suitable for occupation back when the enormous Lake Atna occupied much of the Copper Valley. She imagined that people would have utilized the lake, and were likely to have lived or camped near the shore. Similarly, she could eliminate areas from her search that were likely to have been underwater for the duration of the time period she was interested in.
Geologist Mike Loso was an important part of that team. His expertise in reading the landscape helped to identify where Lake Atna’s shorelines used to be thousands of years ago. There is more than one ancient shoreline, as the level of the lake was not always the same over time.
Reininghaus’ team found almost 70 sites with stone tool fragments and other signs of human use, in several different areas. The sites came from a wide range of dates, and some were not possible to date.
The Copper Lake Trail corridor was identified as a good candidate area for several reasons. Cultural evidence described a long pattern of human use and travel through the area. Geomorphology showed that an ancient lakeshore was nearby a long time ago. The area also has access routes to the high ridgelines that both ancient and modern hunters prefer for upland game hunting, nice camping, and relatively easy travel between one area and another. Upon exploration and excavation, a very promising site was found in that area.
Reininghaus described how the initial excavation immediately uncovered flakes of stone from people making stone tools and charcoal from people making fires. A layer of sand was also found. The sand indicated that the area was on a delta where a creek entered Lake Atna, when the elevation of the shoreline was approximately 777 meters above sea level. White’s team performed analysis and excavation in the same area subsequent to Reininghaus.
Figuring out how long ago people used a particular archaeological site is a big part of the specialized work of archaeology. One technique archaeologists use to date sites is finding and dating hearths. Carbon dating techniques determine approximately how long ago the wood that was burned in the hearth was alive. By contrast, a stone could have formed thousands or even millions of years before someone decided to fashion it into a tool, and the tool making process would not have any impact on its chemistry. Other once living things such as wooden tools, leather, animal bones, etc. can also theoretically be carbon dated if they are in good enough condition. However, these are rarely found in this area because the soil chemistry tends to destroy them over time.
Charcoal from the same layer of the ground where the sand was found was analyzed, and found to be approximately 10,000 years old. Further excavation found charcoal that was dated to at least 12,000 years ago. This work is interesting across disciplines. It provides an approximate date at which Lake Atna’s shoreline was 777 m. It also shows that continuing to look along that 777 m ancient shoreline may help to find more archaeological sites from the same era.
The staggering dates, many thousands of years older than the oldest date of a site heretofore excavated in the Copper Valley, have been confirmed by separate analysis by both Reininghaus’ and White’s teams.
Over 1800 stone tools, tool fragments, and other artifacts associated with stone tool making were found with the combined efforts of Reininghaus’ and White’s teams. None of them were “diagnostic.” That means that so far it is not possible to directly connect the people who left their things at this site with people who left their things in other parts of North America on the basis of similarities between tools.
White discussed some of his examination of the various tools, including traveling through time with his microscope to see the wear patterns of human use on many of the fragments’ edges. He shared that feeling a connection to stone tools was one of the things that inspired him to become an archaeologist.
To the untrained eye, many stone tool pieces look alike. Many of these tools were also fragmented, but White explained that contemporary experiments have helped archaeologists to extrapolate quite a bit from fragments.
There were points that had been sharpened on both sides that could possibly have been used in weapons, tools used to scrape either hides or bark, and a tool that might have been an adze used for woodworking. There was a fine obsidian point that might have been used to make decorative or identifying marks on other tools or weapons. There was one microblade, which White said was a very labor intensive, yet very deadly weapon point that hunters might be motivated to take the time to make when they felt extreme need.
White also highlighted a larger stone that people had chipped away the outside of in order to get to the better quality, unweathered material within. Many of the pieces were found nearby, and much of the block could be reassembled.
White hopes to continue to study this area, both intensively analyzing the little pieces and pondering how they fit into the big picture of human history.
In her future research, Reininghaus will tear herself away from Lake Atna’s shorelines. During the question and answer section of her talk she said it was a difficult decision, but that there were many other areas in the vast expanse of the park that deserve attention. Her future fieldwork will focus on the Beaver Creek drainage.
You can find links to both Reininghaus and White’s lectures at WISE-edu, You can also read Reininghaus’ research article on the ResearchGate website . You can also contact Reininghaus with questions or comments at lee_reininghaus@nps.gov.
By Allison Sayer
