Wave Rock is a natural rock formation that is shaped like a tall breaking ocean wave. The "wave" is about 14 m (46 ft) high and around 110 m (360 ft) long. It forms the north side of a solitary hill, which is known as "Hyden Rock". This hill, which is a granite inselberg, lies about 3 km (2 mi) east of the small town of Hyden and 296 km (184 mi) east-southeast of Perth, Western Australia. Wave Rock and Hyden Rock are part of a 160 ha (395-acre) nature reserve, Hyden Wildlife Park.
A wall lies above Wave Rock and about halfway up Hyden Rock and follows the contours of the wall. It collects and funnels rainwater to a storage dam. The wall and dam were constructed in December 1928 by the Public Works Department for the original settlers of East Karlgarin District. Both were renovated in 1951 to increase water capacity for the Hyden Township. Such walls are common on many similar rocks in the Wheatbelt.
Hyden Rock, of which Wave Rock is part, consists of 2.63 billion year-old biotite K-feldspar porphyritic monzogranite that is part of the Yilgarn Craton. Hyden Rock is a granite inselberg, which consists of three domes. The central and western domes are separated by a deep valley, which is now occupied by a reservoir. The central and eastern domes are linked by a low platform. A multistage process of landform development created these domes. The initial step in the development of Hyden Rock was the subsurface alteration by weathering of granite bedrock beneath a lateritised land surface during the Cretaceous Period between 100–130 million years ago. Depending on the degree to which it was fractured by jointing, the granite bedrock underlying this surface was altered to varying depths beneath the land surface. This process formed underground "domes" of solid granite bedrock surrounded by deeply weathered, relatively loose, and disaggregated granite. Following separation of Australia and Antarctica and accompanying tilting of what became southwestern Australia, periodic erosion of the deeply weathered granite, which underlaid the surrounding land surface, exposed these buried solid bedrock domes over time as Hyden Rock.
Wave Rock is a spectacular example of what geomorphologists call a "flared slope". A flared slope is a concave-upward or -inward bedrock surface that is typically found around the base of inselbergs, bornhardts, and granitic boulders and also on their higher slopes. Flared slopes like Wave Rock are particularly well developed in granitic landforms of south-western and southern Australia. The flared slopes are argued to have formed by the concentrated chemical weathering around the base of an inselberg by groundwater. The chemical weathering of the bedrock by groundwater produces a concave-upward or –inward pocket of deeply weathered, relatively loose, and disaggregated bedrock within the formerly solid bedrock base of an inselberg. When the land surface, which is underlain by deeply weathered bedrock, around an inselberg is lowered by erosion, the pocket of deeply weathered disaggregated bedrock is also removed to produce a flared slope such as Wave Rock. It has also been argued that flared slopes can form during erosion of slopes of inselbergs.
In popular culture
The site of Wave Rock was used as a backdrop for an episode of Japan's Next Top Model in 2008. It featured some comedic bloopers containing an inebriated Australian attempting to run up the course of the rock.
The rock was also mentioned in the popular video game franchise "Sly Cooper".
In the game show "Where in the World is Carmen Sandiego?", one of the episodes featured the theft of Wave rock.
Wave Rock Weekender
Wave Rock hosts the nearby Wave Rock Weekender event, a music festival held once a year. In 2012 the event was held on 29–30 September.
- Twidale, C. R. (1968) Origin of Wave Rock, Hyden. Transactions of the Royal Academy of South Australia. vol. 92, pp. 115–124.
- Qiu, Y., and N. J. McNaughton (1999) Source of Pb in orogenic lode-gold mineralisation: Pb isotope constraints from deep crustal rocks from the southwestern Archaean Yilgarn Craton, Australia. Mineralium Deposita. 34:366–381.
- Twidale, CR., J.A. Bourne, and J.R. Vidal Romani (2002) Multistage Landform Development in Various Settings and at Various Scales. Cadernos do Laboratorio Xeolóxico de Laxe. 27:55–76.
- Twidale, C. R., and J. R. V. Romani (2005) Landforms and Geology of Granite Terrains. Taylor & Francis, New York, 359 pp.