Geochemical basalt investigation reveals procurement strategy at the Acheulian site of Gesher Benot Ya‘aqov, Dead Sea Transform, Israel

The production of bifaces is a central feature of the Acheulian culture, reflecting complex planning, material selectivity, and skilled execution. At Gesher Benot Ya'aqov (GBY), a key early Middle Pleistocene site situated within the tectonically active northern segment of the Dead Sea Transform, basalt served as a significant raw material used for the manufacture of giant cores, bifaces (handaxes and cleavers), and associated debris. However, the geological instability of the region, together with the burial and erosion of basalt flows, complicates the identification of the sources exploited by GBY hominins. Here we apply a set of geochemical analyses including major elements, trace elements, rare earth elements, and multivariate statistical approaches to basalt artifacts and regional geological samples, including subsurface drill cores. These data reveal the compositional range of basalts available around GBY and allow the mapping of archaeological specimens onto this geochemical landscape. The results demonstrate that most artifacts were produced from basalt flows immediately surrounding the site, while a subset of tools particularly some cleavers reflect the use of additional flows not currently exposed at the surface. Together, these findings clarify the raw-material procurement strategies employed by GBY hominins and highlight a selective, structured approach to basalt exploitation within a dynamically changing landscape. The integration of geological and archaeological evidence offers new insights into the planning depth, technological behavior, and adaptive strategies of Acheulian populations in the Jordan Valley.