Temporal evolution of mantle temperature and lithospheric thickness beneath the ∼1.1 Ga Midcontinent Rift, North America: Implications for rapid motion of Laurentia

•Melting conditions in 1.1 Ga Keweenaw Large Igneous Province, Midcontinent Rift.•Major and trace element modeling constrain mantle temperature and melting depths.•Lithospheric thickness decreased from >85 km to 85-100 km thick lithosphere) and high mantle potential temperatures (>1480-1630°C) related to the plume. Potential temperatures decreased to near-ambient conditions (∼1400-1445°C) during the latter portion of the Early phase, with these lower temperatures persisting throughout the Latent (1104-1098 Ma) and Main (1098-1090 Ma) phases. Major element-derived pressures of melt equilibration place broad constraints on lithospheric thickness, which