The rheology of Earth’s upper mantle determines its deformation in response to evolving stress at time-scales ranging from seconds (seismic waves) to millions of years (mantle convection). A holistic, multiscale understanding of mantle rheology is therefore necessary to describe geophysical observations probing plate tectonic processes at various length and time-scales. Laboratory experiments on mantle materials have quantified microphysical mechanisms that impact anelastic and viscous deformation. This has enabled insights into the thermo-mechanical state of the mantle from geophysical observations, and geodynamic models that employ more realistic mantle rheologies. We invite contributions that integrate geophysical observations (e.g., seismic velocity, anisotropy, attenuation), laboratory experiments on mantle materials, and/or geodynamic modeling to better constrain upper-mantle rheology. This includes studies that address discrepancies between observations and experimental predictions, explore the role of partial melt, volatiles, and compositional heterogeneity on rheology, or develop new frameworks for translating geophysical/petrological observations into mechanical properties.

• G - Geodesy
• MR - Mineral and Rock Physics
• S - Seismology
• T - Tectonophysics