Hooft, EmilieMcVey, Brennah2019-09-182019-09-182019-09-18https://hdl.handle.net/1794/24890Despite multidisciplinary evidence for crustal magma accumulation below Santorini Volcano, the structure of the shallow magmatic system remains elusive. We use tomographic inversions of P-wave, active-source seismic data to identify a pronounced low-velocity anomaly, 2.8-5.4 km below the northern caldera basin, which causes seismic attenuation and ray-bending. After extensive synthetic testing, we constrain the shape, volume, and melt-content of shallow, inter-caldera magma storage. Low-velocities are elongated ~15 km NE-SW, attributed to a thin mush region (6-12% melt) confined by tectono-magmatic lineaments, which extends from an inter-caldera magma chamber (15-25% melt). The main magma chamber is consistent with depth estimates of pre-eruptive storage and a recent inflation episode. We suggest magma accumulation under Santorini is controlled by crustal extension and local edifice loads. Our results provide the first structural constraints of Santorini’s upper crustal magma system during inter-caldera periods.en-USAll Rights Reserved.Magma ChamberSantoriniSeismic ImagingShallow Magmatic SystemTomographyVolcanoElectronic Thesis or Dissertation