Definition of underthrust in English:


Line breaks: under|thrust
Pronunciation: /ˈʌndəθrʌst

verb (past and past participle underthrust)

[with object]
  • 1Force (a crustal plate or other body of rock) beneath another formation: the Farallon plate was being underthrust beneath the North American plate (as noun underthrusting) this sediment may be deformed by the underthrusting
    More example sentences
    • 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.
    • 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.
    • 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 formation): plate X is underthrusting plate Y in a NE direction


Back to top  
  • An instance of one crustal plate or other body of rock being forced underneath another: the westward underthrust of the Pacific Ocean plate
    More example sentences
    • 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.

More definitions of underthrust

Definition of underthrust in:

Get more from Oxford Dictionaries

Subscribe to remove adverts and access premium resources

Word of the day astrogation
Pronunciation: ˌastrə(ʊ)ˈgeɪʃ(ə)n
(in science fiction) navigation in outer space