This Western Australian Fractured Rock Province dataset contains descriptive attribute information for the areas bounded by the relevant spatial groundwater feature in the associated Hydrogeology Index map. Descriptive topics are grouped into the following themes: Location and administration; Demographics; Physical geography; Surface water; Geology; Hydrogeology; Groundwater; Groundwater management and use; Environment; Land use and industry types; and Scientific stimulus.
The geological evolution of Australia can be summarised as a west-to-east growth pattern, resulting from the assembly and disintegration of several supercontinents since the Archean era. The oldest rocks are found in Western Australia, specifically within the Western Australia fractured rock province, which consists of two crustal elements: the West Australian Element and the Pinjarra Element. The Yilgarn and Pilbara cratons in the West Australian Element host the oldest rocks in continental Australia, featuring high-grade gneiss belts, granite-greenstone belts, and significant gold and iron ore deposits.
The Yilgarn Craton is older in the west and can be divided into several terranes, with the eastern regions hosting world-class gold deposits. The Pilbara Craton, on the other hand, consists of granitoid-greenstone terrain and is rich in banded iron formations, leading to the world's richest iron ore deposits in the Hamersley Basin. The Gascoyne Province forms the medium- to high-grade metamorphic core of the orogeny in the West Australian Element.
The Albany-Fraser Orogen and Paterson Orogen joined the West Australian Element with the South Australian and North Australian Elements, respectively, and are characterised by metamorphosed rocks of various facies. The Pinjarra Orogen, situated to the west of the Yilgarn-Pilbara block, contains granulite and amphibolite facies orthogneisses.
In the Phanerozoic era, sedimentary cover occurred in various large and smaller basins in Western Australia. The West Australian Element, along with the adjoining orogens, is treated as the West Australian fractured rock province, primarily reliant on weathered and fractured zones for groundwater storage due to low permeability.
These cratons and orogens have been exposed since the Precambrian or Late Palaeozoic era, experiencing substantial weathering and river valley development. Modern palaeovalleys are mainly infilled with Cenozoic sediments, while arid conditions have reduced active watercourses, leading to an abundance of Aeolian sand cover. Many of these palaeovalleys are no longer active as rivers but can still be identified topographically.
Overall, the geological history of Australia reveals a complex and diverse landscape, with Western Australia playing a significant role in hosting some of the continent's oldest rocks and valuable mineral deposits.
