Geochemical discrimination of Baekdusan and Kyushu obsidian using instrumental neutron activation analysis

Abstract

Obsidian is a key research subject in geological studies on volcanic activity and magmatic processes as well as in provenance research in archeology. In this study, the geochemical characteristics of obsidian samples from Baekdusan (Korea) and Kyushu (Japan) were compared to better understand their formation processes and regional differences. Instrumental Neutron Activation Analysis (INAA) of the minor and trace element compositions of the samples revealed distinct geochemical signatures specific to each region. These differences reflect variations in the magma composition, cooling rate, and tectonic settings. Furthermore, geochemical "fingerprinting" of obsidian provides valuable insights for tracing the provenance of archaeological artifacts. The INAA-based analytical tool provides deeper insight into geological processes and prehistoric cultural exchange networks.