Rapid and high-resolution handheld X-ray backscatter subsurface imaging for field archaeology prediction

Rapid acquisition of millimeter-resolution subterranean images can significantly improve the efficiency of archaeological excavation and facilitate the preservation of artifacts. For excavation sites with limited space, small and portable imaging equipment is necessary. Compton backscatter imaging (CBI) is a single-sided non-destructive testing technique, which typically requires a short scan time to obtain high-resolution images. It has great potential in archaeological excavation, supporting archaeologists to make quick judgments. This research utilized a compact, easy-to-carry handheld backscatter system, making it particularly suitable and beneficial for on-site archaeological excavation. Tests were performed in the framework of the excavation of a chariot pit at Dajuan Han Tomb in Xi'an (Shaanxi Province, China) to validate the applicability of this technique in imaging soil structure changes and detecting cultural artifacts. The experimental results show that CBI can clearly image bronze artifacts buried underground, which means practical value in archaeological excavation.