PI: E. Attias (UTIG)
co-PIs: S. Naif (Georgia Tech), T. Becker (UTIG)
Collaborators: M. Agius (University of Malta), Claudio Faccenna (GFZ)
maRine electrO-seismic Toroidal mAnTle flOw imaging expeRiment
Tectonic-driven passive rifting and mantle plume-driven active rifting are two mechanisms frequently invoked as the cause of continental breakups. Both mechanisms result in thermo-mechanical erosion of the lithosphere, which leads to thinning and rupture of the plate. Rifting in melt-poor and complex tectonic settings (i.e., at the boundary between subduction and rift margins) is poorly constrained. Studying rifting in such settings is essential to understand the role of individual and multiparametric mechanisms in the overall rifting process. For example, the toroidal mantle flows around the edge of a subducting slab, and its influence on the adjacent continental plate is characterized by cascading processes that may lead to incipient continental breakup and new spreading rifts. Such a complex tectonic setting exists across the Sicily Channel Rift Zone (SCRZ). However, marine observations to constrain SCRZ’s mantle flow and its effect on the overlying lithosphere are limited.
Evidence for crustal dynamics from intraplate and subduction-related volcanism (Faccenna et al., 2005), compression/extension (Devoti et al., 2011; Bahrouni et al., 2020), heat flow (Fuchs et al., 2021), seismic azimuthal/radial anisotropy and crustal thickness (Agius et al., 2022).
What do we know about SCRZ from existing shallow datasets?
What do we know about SCRZ from existing deep datasets?
Evidence for upper mantle flow due to dynamic slab. Shear velocity structure at 100~km depth adopted from El-Sharkawy et al., (2020), shear-wave splitting from Barruol et al., (2009), and seismic surface-wave radial and azimuthal anisotropy data from Agius et al., (2022).
The ROTATOR project aims to understand the role of complex tectonics on continental breakups. We will collect passive and active marine EM, seismic, magnetic, oceanographic, and biogeochemical datasets at SCRZ to combine with analogue and numerical geodynamic models. Studying SCRZ’s intricate tectonics can promote our knowledge of when/why plate tectonics developed on Earth, the different processes that govern regional volcanism, and how critical elements circulate Earth over broad spatiotemporal scales.
The ROTATOR experiment: A 2-cruise survey plan. Recovery of MT and OBS stations after a year from deplyoment.
Proposal to be submitted to NSF-OCE in December 2023