Transpression

Simple model for transpression: strike-slip zone with an additional and simultaneous shortening across the zone. Also induces vertical uplift.

In geology, transpression is a type of strike-slip deformation that deviates from simple shear because of a simultaneous component of shortening perpendicular to the fault plane. This movement ends up resulting in oblique shear. It is generally very unlikely that a deforming body will experience "pure" shortening or "pure" strike-slip. The relative amounts of shortening and strike-slip can be expressed in the convergence angle alpha which ranges from zero (ideal strike-slip) to 90 degrees (ideal convergence). During shortening, unless material is lost, transpression produces vertical thickening in the crust. Transpression that occurs on a regional scale along plate boundaries is characterized by oblique convergence.[1] More locally, transpression occurs within restraining bends in strike-slip fault zones.

  1. ^ Dewey, J. F.; Holdsworth, R. E.; Strachan, R. A. (1998-01-01). "Transpression and transtension zones". Geological Society, London, Special Publications. 135 (1): 1–14. Bibcode:1998GSLSP.135....1D. CiteSeerX 10.1.1.519.2389. doi:10.1144/GSL.SP.1998.135.01.01. ISSN 0305-8719.