New chronology of the deposits from the inner chambers of the Guanyindong cave, southwestern China

Guanyindong Cave is one of most important Palaeolithic sites in southwestern China, due to its presence of the earliest Levallois artifacts in East Asia, which was dated to two discrete periods at similar to 160-170 thousand years ago (ka) and similar to 70-80 ka, respectively, based on optical dating of the artifact-bearing sediments from the west entrance of the cave (Hu, et al., 2019a). There were five excavation pits at Guanyindong during the initial excavation seasons in 1960s, all of which have yielded abundant stone artifacts and fauna fossils. However, in contrast to the excavation pits at the west entrance whose chronology and lithic industry were intensively studied, the chronological frameworks of the excavation pits inside the cave chambers have not been established. Here we report optical dating results of sediment samples taken from two of the pits inside the cave (Profiles 2A and 3). We established Bayesian age models for the two profiles based on our new optical ages and the U-series ages obtained in previous studies. Our results indicate that the group B deposits in the main chambers of the cave accumulated between similar to 200 ka and similar to 100 ka. The chronology of the deposits from the inner chambers, together with those from the west entrance, provided a new age constraint for the Levallois artifacts from the site and suggested that hominins occupied the cave from similar to 180 ka to similar to 80 ka, spanning a full glacial and interglacial period (from MIS 6 to MIS 5).

Automated summary

Guanyindong Cave is an important Palaeolithic site in southwestern China, where the earliest Levallois artifacts in East Asia have been found. The artifacts were dated to two discrete periods approximately 160-170 thousand years ago and approximately 70-80 thousand years ago. Optical dating and previous U-series dating were used to establish chronological frameworks for the cave's excavation pits, providing insight into the occupation of the cave by hominins from approximately 180 ka to approximately 80 ka.