Key Points:
• P wave tomography of the upper crust (<3 km) around Santorini delineates basin structures including buried margins and basement faults
• These structures, also seen in seismic reflection images, result from both the integrated tectonic history, as well as ongoing deformation
• Tectonic structures and stresses localize volcanism in regional NE-SW basins, and, within Santorini caldera, along local NE‐SW lineaments
