Australia's Great Dividing Range is the largest mountain range on the continent, running down the length of the eastern part of the continent, as shown in the Geoscience Australia map as a dark line, below:

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The tallest peak in the range is Mt. Kosciuszko at 2228 m asl. The Wikipedia entry is rather vague about the formation, with

The Great Dividing Range was formed during the Carboniferous period—some 300 million years ago—when Australia collided with what is now parts of South America and New Zealand. The range has experienced significant erosion since.

it is particularly vague regarding the question - What is the tectonic setting for the formation of the Great Dividing Range in Australia?

The tectonic history of Australia's Great Dividing Range is very complex, extending back into the Neoproterozoic era (1), and is far more complex than the Wikipedia quote. Additionally, evidence (shown in this answer) demonstrated that the eastern third of the Australian landmass is comprised of accreted arc systems that developed along the continental-oceanic Eastern Gondwana boundary following the initiation of subduction in the late Neoproterozoic (1) forming in a series orogenies (as shown on the map below (2) - not due to a single continental collision. These orogenies are incorporated in the 'Terra Australis' Orogen that ceased approximately 230 million years ago (3).

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As can be seen by the diagram below (2), the youngest accreted orogen occurs in the eastern most margins of the Australian landmass, where the Great Dividing Range is.

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Also, the cessation of arc accretion, did not end the tectonic story affecting the Great Dividing Range. Large Igneous Province volcanics occurred in north Queensland in the early Cretaceous, then epeirogenic uplift, exhumation and continental rupturing culminating in the opening of the Tasman Basin occurred in the mid Cretaceous, leading to the separation of Zealandia (New Zealand + submerged continental shelf) and giving shape to the eastern Australian coastline (and eastern boundary of much of the Great Dividing Range) (4). The rifting process is illustrated below

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Image source: Formation of The Australian Alps

References

(1) Cawood et al. 2009 Accretionary orogens through Earth history, The Geological Society

(2) Foster and Goscombe, 2013 Continental Growth and Recycling in Convergent Orogens with Large Turbidite Fans on Oceanic Crust, Geosciences

(3) Cawood, 2005, Terra Australis Orogen: Rodinia breakup and development of the Pacific and Iapetus margins of Gondwana during the Neoproterozoic and Paleozoic, Earth-Science Reviews

(4) Bryan et al. 2012, Early-mid Cretaceous tectonic evolution of eastern Gondwana: From silicic LIP magmatism to continental rupture, Episodes

  • I interpret this to mean that although the underlying geology is very complicated, the actual topography is a result of Cretaceous/ Paleogene rifting. – Spencer Aug 25 '17 at 18:02

When describing the development of a mountain range, a clear distinction must be made between the origin of the rocks that are found in the mountain range, and the development of the current topographic high that defines the mountain range. The Great Dividing Range, as the topographic high that we see today, was developed from the Cretaceous into the Tertiary. Some of the rocks found in the Great Dividing Range have been part of earlier mountain ranges that were eroded away before the Permian.

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