Relatrice: Janneke de Laat, University of Twente, Nederland

Titolo: Project SEA-SEIS: Imaging the mantle below the North Atlantic using Ocean Bottom Seismometers

Contenuti: The North Atlantic region is shaped by complex mantle dynamics, driven by the Iceland plume and its interaction with the Mid-Atlantic Ridge. To better understand these processes, Project SEA-SEIS deployed 18 broadband ocean-bottom seismometers (OBS) across the northeast Atlantic to better understand these processes, recording continuous seismic data for 19 months (2018–2020). Fourteen instruments were successfully retrieved, with 12 providing high-quality data. Data pre-processing included clock-drift correction, horizontal component orientation determination, and suppression of compliance and tilt noise to enhance signal quality. Using this dataset, combined with a global seismic dataset, we developed NA25_UM, a new high-resolution seismic waveform tomography model of the North Atlantic upper mantle. The model reveals a complex Iceland plume structure, suggesting that the plume rises beneath Greenland in the transition zone before migrating diagonally toward Iceland and rising vertically and outward along the ridges above 200 km depth. Additionally, the azimuthal anisotropy results indicate a strong southward channelized flow from the Iceland plume beneath the Reykjanes Ridge, with no evidence of radial outward dispersion.In this talk, I will take you through the SEA-SEIS expedition, the data pre-processing, the inversion procedure and the resulting upper mantle tomography model, providing new insights into the dynamics and evolution of the Iceland plume.

Per chi non potesse partecipare in presenza, è possibile seguire l'evento online tramite il seguente link Teams:

https://teams.microsoft.com/l/meetup-join/19%3ameeting_ZGYyYWYwZjgtZjFhZ...