Mount Desire Dyke
Mount Desire Dyke is designated place of geological significance. It is located 16 km (9.9 mi) north-east of Hawker in South Australia, on the edge of the Flinders Ranges. The dyke (or dike) is a rock structure where heat-softened igneous rock has intruded into cracks in folded Adelaidean sediments in the geological past.[1]
On the State Heritage Register the site is described as significant because "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 breccia and a large limestone xenoclast of probable Willouran origin; sharp irregular and distinctive contacts with early Cambrian Parara 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."[2]
References
- Morrison, Robert Sinclair. Igneous Intrusive Rocks of the Peake and Denison Ranges within the Adelaide Geosyncline. OCLC 220669511.
- "Mount Desire Dyke (designated place of geological significance)". SA Heritage Places Database Search. Government of South Australia. 30 March 1998. Retrieved 24 January 2020.