Australia: The Land Where Time Began

A biography of the Australian continent 

Musgrave Province

The Musgrave Province, of Mesoproterozoic age, is in a geographically central location within Australia, covering an area of about 120,000 km^2, bounded by older regions that are more  isotopically evolved, such as the Gawler Craton in South Australia, and the Arunta Region in the northern Territory.

Lithologic units ranging in age from earliest Mesoproterozoic to Neoproterozoic, make up the Musgrave Province. The Musgrave provinces is one of the few Australian terrains with significant tectonism of Grenvillian age, and its history is distinctly younger than the surrounding fragments of Australia from the Proterozoic, though the evolution of the Musgrave Province is less well understood than that of other Australian terrains from the Proterozoic. There is evidence in the region of development of arc-related magmatism from the earliest Mesoproterozoic, with major additions of juvenile crust, comprising intercalated felsic and mafic gneisses, protolith ages ranging from about 1.60 to 1.54 Ga. Ocean closure between the North Australian Craton and the South Australian Craton occurred following the arc magmatism period at about 1.51 Ga. A period of extension occurred following arc magmatism and collision. During this period, deposition of protoliths to metasedimentary rocks of the Musgrave Province took place at about 1.4 Ga. A provenance from outside Australia, possible sources originating in Laurentia, is suggested by juvenile Nd signature and detrital zircon ages from these metasediments. At about 1.3 and 1.2-1.14 Ga there were granitic magmatic events, the high volume A-type granites of the Pitjantjatjara Supersuite being formed during the latter. Key temporal constraints on events of deformation are provided by magmatic intrusions of these units. They are coeval with high volume A-type suites from Laurentia, suggesting correlation between Australia and Laurentia at about 1.3-1.14 Ga. Episodes of magmatism are accompanied by deformation at granulite facies at about 1.3 Ga (an unnamed event), and the Musgrave Orogeny at 1.23-1.15 Ga.

See Source 1 for more detailed information

Sources & Further reading

1. The Musgrave Province: stitching north, west and south Australia

Links

1. Unravelling the tectonic framework of the Musgrave Province, central Australia
2. Constrained potential field modelling of the crustal architecture of the Musgrave Province in central Australia: Evidence for lithospheric strengthening due to crust-mantle boundary uplift