| Summary: | East Antarctica is the least understood continent involved in the assembly of Gondwana, a key stage in the global supercontinent cycle. Thick crust stretches from Dronning Maud Land to the Gamburtsev Subglacial Mountains, suggesting that the Kuunga Orogen, formed during the collision of India and East Antarctica during Gondwana assembly, had a significant impact on the Precambrian lithosphere of parts of interior East Antarctica. Geological and geophysical research has revealed key aspects of the collisional East African-Antarctic Orogen and the subduction-related Ross Orogen along the paleo-Pacific margin of Gondwana. However, the paths and architecture of these different orogens in the entirely ice sheet covered and remote interior of East Antarctica have remained more difficult to investigate, making it even more challenging to link subduction and collisional processes leading to Gondwana assembly and growth. Here we present a new satellite-conformed aeromagnetic anomaly compilation that includes data recently collected between the interior of Dronning Maud Land and South Pole, together with airborne and satellite gravity imaging and seismological and geological constraints that provide tantalising new views into different crustal provinces, cratons and orogens in interior East Antarctica. We propose that a suture zone, partially exposed in the Shackleton Range, may cross the continent linking major fault systems imaged in the Gamburtsev Province and Princess Elisabeth Land. By superimposing our geophysical layers on a new plate tectonic reconstruction, we explore the potential evolution of accretionary and collisional stages in East Antarctica during the assembly of Gondwana from Edicaran to Cambrian times.
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