Resolving some chronological problems at Nombe rock shelter in the highlands of Papua New Guinea

New AMS radiocarbon dating at Nombe rock shelter in Simbu Province, Papua New Guinea confirms human use from c.25500–19600 calBP and corroborates previous chronostratigraphic interpretations for four major periods of cultural deposition. The original conventional radiocarbon dating program was largely undertaken on bone and flowstones, due to the limitations of dating small charcoal fragments in the 1970s and 1980s before the advent of, and widespread access to, AMS dating. Here, 18 new AMS dates on small fragments of charcoal hand-picked from previously collected sediment samples enable an evaluation that largely confirms previous dating. These findings are significant because they indicate that the chronostratigraphy, at least for the portion of the site redated thus far, is comparatively robust. Primarily, the new dating results indicate the chronostratigraphy for the early and mid-Holocene, a period crucial for understanding the emergence of agriculture in the highlands, is well preserved at the site.