THE CHRONOLOGY OF FREISENHAHN CAVE: DETERMINED BY URANIUM-SERIES DISEQUILIBRIUM DATING OF JUVENILE MAMMOTH ENAMEL

Freisenhahm Cave, located outside of San Antonio, Texas, in the Edwards Plateau, was selected for excavation because it was hoped that early human remains would be found there. The cave was excavated by Glen Evans who recovered a Late Pleistocene fauna including Homotherium and juvenile Mammoth but no human remains. He determined that there were multiple stratigraphic units that indicated several periods where the karstic cave had been opened to the surface allowing periods of deposition and erosion. The teeth were found in zone 3 near the surface. Sporadic excavation of the site has continued by University of Texas and Concordia University. Radiocarbon dating indicated an age of 19,000 years BP on relatively poor material (Evans 1961).

Uranium Series Disequilibrium dating of juvenile Mammoth tooth enamel produced ages of (36E2: 49,000 BP, Error: +8000 -7000) and (39E2: 45,000 BP, Error: +6000 -6000) confirming that early human occupation is unlikely.

References

Evans, Glen L. (1961). "The Friesenhahn Cave." Bulletin Of The Texas Memorial Museum 2: 7-22.