Living Reference Work Entry

Encyclopedia of Planetary Landforms

pp 1-5

Date: Latest Version

Pressure Ridge

  • Henrik HargitaiAffiliated withPlanetary Science Research Group, Institute of Geography and Earth Sciences, Eötvös Loránd University Email author 
  • , Jarmo KorteniemiAffiliated withDepartment of Physical Sciences, University of Oulu
  • , Serina DiniegaAffiliated withJet Propulsion Laboratory, California Institute of Technology


The term pressure ridge is applied to meter-scale ridges made up from platy material, which was fragmented from relatively thin crust and piled up by pressure. Kilometer-scale wrinkle ridges form by similar mechanism. Pressure ridges may be composed of:
  1. (1)

    Lava: An elongate uplift of the congealing thin crust of a lava flow, up-buckled by laterally directed pressure and uncoupled from underlying structure and topography (Bryan 1973; Walker 1991; Neuendorf et al. 2005; Fig. 1) or

  2. (2)

    Ice: Pack ice crushed under pressures (e.g., by winds) into linear or sinuous conglomeration of ice fragments (Fig. 2). The submerged volume under a ridge is termed ice keel (WMO 1989); the rubble above the water line is called the sail (Timco et al. 2000).
Fig. 1

1.5 m high pressure ridge along a 1982 lava flow at Kilauea (From Takahashi and Griggs 1987, p. 883, Photo by T. J Takahashi 1984)
Fig. 2

Ice pressure ridge along Lake Balaton, Hungary (Photo by H. Hargitai 1999)


Meter-scale pressure ...

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