Mount Desire Dyke is designated place of geological significance. It is located north-east of Hawker in

South Australia South Australia (commonly abbreviated as SA) is a States and territories of Australia, state in the southern central part of Australia. With a total land area of , it is the fourth-largest of Australia's states and territories by area, which in ...

, on the edge of the

Flinders Ranges The Flinders Ranges are the largest mountain ranges in South Australia, which starts about north of Adelaide. The ranges stretch for over from Port Pirie to Lake Callabonna. The Adnyamathanha people are the Aboriginal group who have inhab ...

. The dyke (or dike) is a rock structure where mobile material, being a breccia of rock salt and rubble (as in 'salt diapirs') has intruded into cracks in folded Adelaidean sediments in the geological past PhD thesis of Trev J Mount, 1975, on "Diapirs and diapirism in the Adelaide Geosyncline" (Flinders Ranges) now is published online (free download) by the Department of Energy & Mining (Geological Survey of South Australia) as Report Book 2021/00006 The site was added to the

South Australian Heritage Register The South Australian Heritage Register, also known as the SA Heritage Register, is a statutory register of historic places in South Australia. It extends legal protection regarding demolition and development under the ''Heritage Places Act 1993'' ...

on 30 March 1998. Its significance is described as follows:

This site contains a number of features of considerable importance to research and debate concerning the nature and origin of the Mt Desire Dyke and other diapirs of the Flinders Ranges, including: typical dolomitic-vanished evaporite breccia and dolostone/metasediment xenoclasts (to km in size) of probable Willouran origin; sharp irregular and distinctive contacts with early Cambrian units such as the Mernmerna Formation, Oraparinna Shale, and Wilkawillina Limestones, including a particularly important apophysis interpreted as an intrusive re-entrant; and significant brecciation in, and metamorphic incongruence between, the material of the dyke and the adjacent Cambrian limestones.

References

Far North (South Australia) South Australian Heritage Register {{Australia-geology-stub

See also

References