Evolution of the Transantarctic Basin (Southern Gondwana): Insights From Quantitative Sandstone Petrography

The deposition of the sandstone sedimentary succession of the Beacon Supergroup lasted more than 200 Myr (Devonian to Early Jurassic) in Victoria Land and nearby territories in the so-called Transantarctic Basin, recording crucial events in the history of the Earth. Sedimentation is synchronous with the convergence between the paleo-Pacific plate and Gondwana, to form the large Gondwanide orogenic system. The composition of the Beacon Supergroup sandstones was found to be correlated with major tectonic processes in response to subduction dynamics, which ultimately conditioned the source-to-sink system and provenance imprints. Petrographic variability in sandstone composition is tracked through space and time by a quantitative analysis of all available published data and new updated ones, from the Transantarctic Mountains and Tasmania. The variability of grain composition detected by quantitative sandstone petrography reveals that the Victoria Land sector transitioned from an intracratonic basin in back-bulge position to a foredeep basin setting.