Útdráttur:
Seismic imaging of the subsurface at volcanoes is crucial for hazard assessment, geothermal exploration, and understanding magma transport within plumbing systems. However, strong geological heterogeneity in volcanic regions makes high-resolution imaging particularly challenging. At Krafla volcano in northeast Iceland, rhyolitic magma was unexpectedly encountered at 2.1 km depth in the IDDP-1 borehole, offering a unique benchmark for geophysical imaging. Using data from a dense temporary seismic network, this study refines earthquake-based reflection imaging techniques to delineate subsurface structures around IDDP-1. Data-driven processing, including the application of a resonance-removal filter, and imaging methods tailored to highly scattering media—such as an adapted migration workflow—reveal coherent phases consistent with reflections from the magma–rock interface at 2.1 km depth. The reflector extends over an area of at least 770 m and is located in the apex of an updoming local brittle–ductile transition within the Krafla geothermal system. These findings demonstrate the potential of passive seismic approaches to resolve fine-scale structures in complex volcanic settings and advance our understanding of magma storage and migration at Krafla.
Öll velkomin!