Table 1.

Relative timing, kinetics and products of fault activity along the Outer Hebrides Fault Zone from the Grenvillian to the Caledonian orogeny, including possible post-Caledonian activity based on observations from the island of Barra

Tectonic eventMain fault productsOrogeny/age (Ma)
Top-to-the-NW ductile thrustingMylonitesGrenville/1100–1000
Top-to-the-NW brittle thrustingCataclasites, pseudotachylytesCaledonian/490–390
Top-to-the-E–NE sinistral strike-slipPhyllonitesCaledonian/490–390
Top-to-the-ENE–ESE dip-slip extension on low-angle faultsPhyllonitesCaledonian/490–390
Top-to-the-ENE–ESE dip-slip extension on high-angle faultsCaledonian/490–390
WNW–ESE oblique extensional and reverse strike-slip faultsMesozoic(?)/>250

Modified from Fettes & Mendum (1987), MacInnes et al. (2000), Osinski et al. (2001) and Imber et al. (2002).