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A Journey to a New Land

Caribou Hunt
Post secondary Level Resources

Meadowcroft Rockshelter

Meadowcroft Rockshelter, located in southwestern Pennsylvania, stands as one of the most published, and most contested, archaeological sites in the Americas.

The site was first excavated between 1973 and 1978 by a team led by archaeologist James M. Adovasio. Although initial radiocarbon dates indicated that the rockshelter may have been occupied as early as 19,000 years BP, the samples that yielded those dates were very small. Adovasio instead suggests that by a very conservative estimate, the site was occupied by about 14,000 years BP, which is at least two thousand years before Clovis points first appeared in North America.

Meadowcroft holds the distinction of demonstrating the longest occupational sequence of humans in the Americas. The numerous occupation layers contained over 2,000 stone flakes and tools, 150 fire pits and 1 million animal remains. A heavily cut and burnt deer antler base, dated to 16,175±975 years BP was the oldest bone found at the site.

Artifacts from the lowest cultural layers include bifaces, unifacial knives, projectile points, and small, prismatic blades. The small blades, struck from a prepared core, are not found at later Clovis sites.

While most archaeologists agree that Meadowcroft was occupied by about 12,000 years BP, the earlier radiocarbon dates have come under heavy scrutiny. Some archaeologists suggested that the dating samples may have been contaminated by coal particles, or by carbon dissolved in the groundwater. This contamination would result in older dates for the specimens. However, Adovasio counters that all samples were rigorously tested for coal contamination, and that subsequent radiocarbon testing using a technique known as accelerator mass spectrometry confirmed the early dates. In addition, an independent geomorphologist inspected samples from Meadowcroft and concluded that no evidence of groundwater activity could be seen.

Although a few archaeologists continue to challenge the validity of the pre-Clovis dates, many believe that the Meadowcroft Rockshelter assemblage demonstrates solid evidence for a pre-Clovis occupation of the Americas.

Meadowcroft Rockshelter

Further Reading:

Adovasio, J. M., D. R. Pedler, J. Donahue and R. Stuckenrath
1998 Two Decades of Debate on Meadowcroft Rockshelter. North American Archaeologist19(4):317-341.

Carlisle, R.C. and J. M. Adovasio, Editors
1982 Meadowcroft: Collected Papers on the Archaeology of Meadowcroft Rockshelter and the Cross Creek Drainage. University of Pittsburgh, Department of Anthropology.