As ice wedges grow, they push up the soil at the edges into ramparts; see M. Shahgedanova (2002). Protalus ramparts are coarse, angular, non-stratified thin ridges of rock fragments, about 1 m high, lying along the base of a mountain face. They are associated with persistent snow banks (Sass (2006) Geomorph. 80, 1–2). Shakesby et al. (1999) Geografiska A 81, 1 show that they can be formed by snow-push.