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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 theGeoscience Australia地图作为一个黑暗行,如下:

enter image description here

The tallest peak in the range isMt. Kosciuszko at 2228 m asl.TheWikipedia entryis 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?

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    2 Answers2

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    The tectonic history of Australia's Great Dividing Range is very complex, extending back into the Neoproterozoic era (1), and isfarmore 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).

    enter image description here

    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.

    enter image description here

    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

    enter image description here

    Image source:Formation of The Australian Alps

    References

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

    (2) Foster and Goscombe, 2013Continental 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

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    • $\begingroup$ I interpret this to mean that although the underlying geology is very complicated, the actual topography is a result of Cretaceous/ Paleogene rifting. $\endgroup$
      Spencer
      Aug 25, 2017 at 18:02
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    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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