oa Large Igneous Province

Large igneous provinces (LIPs), voluminous emplacements of predominantly mafic extrusive and intrusive rock, originate via processes other than those responsible for the creation of crust in the plate tectonic cycle, i.e., 'normal' seafloor spreading and subduction. They are produced when ascending hot plumes of mantle material reach the upper crust, and are generally considered to be relatively or totally independent of the movement of the Earth's lithospheric plates. LIPs and plumes therefore manifest a mode of mantle circulation not accounted for in the existing plate tectonics paradigm.