Crustal architecture of the Wilkes Subglacial Basin in East Antarctica, as revealed from airborne gravity data

摘要: The Wilkes Subglacial Basin, in the hinterland of Transantarctic Mountains, represents one least understood continental-scale features Antarctica. Aeromagnetic data suggests that this basin may be imposed on a Ross age back arc region adjacent to East Antarctic Craton. However, evolution deeper crustal structure is disputed. Here, we present new airborne gravity reveals architecture northern Basin. Our models indicate crust under Basin 30–35 km thick, i.e. ca 5–10 thinner than imaged and ~ 15 predicted from some flexural seismic southern We suggest thickening Victoria Land reflects Ross-age (ca 500 Ma) orogenic events. Airy isostatic anomalies along both flanks reveal major inherited tectonic structures, which likely controlled location, supporting aeromagnetic interpretations as structurally basin. positive anomaly western margin defines boundary between Craton Orogen, its eastern flank high-grade rocks central Wilson Terrane. 5 beneath compared formerly contiguous segments Delamerian Orogen south-eastern Australia. linked to: i) back-arc formation or collapse processes segmentation within Ross\Delamerian ii) Jurassic Cretaceous extension prior break-up Australia Antarctica, iii) Cenozoic glacial erosion most likely, iv) combination these processes.