Contemporaneous assembly of Western Gondwana and final Rodinia break-up: Implications for the supercontinent cycle
Zeitschrift: Geoscience Frontiers, 20178, 6: 1431 - 1445
DOI: https://doi.org/10.1016/j.gsf.2017.01.009
Persistent URL: http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/7064
Persistent URL: http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/7064
Oriolo, Sebastián; Oyhantçabal, Pedro; Wemmer, Klaus; Siegesmund, Siegfried, 2017: Contemporaneous assembly of Western Gondwana and final Rodinia break-up: Implications for the supercontinent cycle. In: Geoscience Frontiers, Band 8, 6: 1431 - 1445, DOI: 10.1016/j.gsf.2017.01.009.
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Geological, geochronological and isotopic data are integrated in order to present a revised model for the
Neoproterozoic evolution of Western Gondwana. Although the classical geodynamic scenario assumed
for the period 800e700 Ma is related to Rodinia break-up and the consequent opening of major oceanic
basins, a significantly different tectonic evolution can be inferred for most Western Gondwana cratons.
These cratons occupied a marginal position in the southern hemisphere with respect to Rodinia and
recorded subduction with back-arc extension, island arc development and limited formation of oceanic
crust in internal oceans. This period was thus characterized by increased crustal growth in Western
Gondwana, resulting from addition of juvenile continental crust along convergent margins. In contrast,
crustal reworking and metacratonization were dominant during the subsequent assembly of Gondwana.
The Río de la Plata, Congo-São Francisco, West African and Amazonian cratons collided at ca. 630
e600 Ma along the West Gondwana Orogen. These events overlap in time with the onset of the opening
of the Iapetus Ocean at ca. 610e600 Ma, which gave rise to the separation of Baltica, Laurentia and
Amazonia and resulted from the final Rodinia break-up. The East African/Antarctic Orogen recorded the
subsequent amalgamation of Western and Eastern Gondwana after ca. 580 Ma, contemporaneously with
the beginning of subduction in the Terra Australis Orogen along the southern Gondwana margin.
However, the Kalahari Craton was lately incorporated during the Late EdiacaraneEarly Cambrian. The
proposed Gondwana evolution rules out the existence of Pannotia, as the final Gondwana amalgamation
postdates latest connections between Laurentia and Amazonia. Additionally, a combination of introversion
and extroversion is proposed for the assembly of Gondwana. The contemporaneous record of
final Rodinia break-up and Gondwana assembly has major implications for the supercontinent cycle, as
supercontinent amalgamation and break-up do not necessarily represent alternating episodic processes
but overlap in time.
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- Geologie [930]
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