Reconstructing history: 3D high-resolution GPR analysis based on SAR discoveries in the ancient Siniyah Island of Umm Al-Quwain, United Arab Emirates

The Siniyah Island in Umm Al-Quwain is one of the pearls of the United Arab Emirates. Archaeologists have discovered vivid evidence that brought to light a vibrant multicultural past occupation. Among the substantial findings were tools of prehistoric settlements, a Christian monastery and a wide marine trading network between the Arabian Gulf and other far regions. These revelations deliver a valuable depiction of the socio-economic, cultural, and religious dynamics of the Siniyah Island prior to the Islamic era. Here, we present for the first time on the island, A high-resolution Ground Penetrating Radar (GPR) survey was carried out in three priority areas delineated through an integrated Synthetic Aperture Radar (SAR) analysis and machine-learning–based spatial screening. SAR tomography provided intermediate-scale subsurface assessment, reducing spatial uncertainty prior to field investigation. The subsequent GPR surveys enabled detailed imaging and three-dimensional reconstruction of buried structures, allowing validation and refined characterization of candidate archaeological features. Despite the anticipated theoretical hostile conditions to investigate electromagnetic waves, GPR results perfectly align with the geometry of the unearthed ancient structures. In addition to the known archaeological sites, GPR data, analyzed through B-scans, C-scans, and three-dimensional models, reveal a high concentration of sharp anomalies resembling archaeological features, suggesting that the island was once home to a high-density ancient population.