1 Force (a crustal plate or other body of rock) beneath another plate or block.
- ‘Here the Papua New Guinea continental crust appears to be underthrusting the adjacent marginal basin and obduction of the ophiolite is occurring in an uphill direction.’
- ‘Patterns of this type can be readily explained by accretionary tectonism, whereby a packet of sediment accreted at the toe of the prism is underthrust and buried beneath an overburden of older strata.’
- ‘The tensional stresses in the uplift can be relaxed by, for example, underthrusting in a subduction zone, or contraction in surrounding regions.’
- 1.1Be forced underneath (another plate or block)
An instance of one plate or block being forced underneath another.
- ‘We suggest that because the upper portion of underthrust sections lacked any thick, water-saturated clastic deposits this did not favour the formation of melanges.’