The Gondwana Plate margin in the Weddell Sea sector: Zircon geochronology of Upper Paleozoic (mainly Permian) strata from the Ellsworth Mountains and eastern Ellsworth Land, Antarctica

New geophysical compilations link crustal block motion to Jurassic extension and strike-slip faulting in the Weddell Sea Rift System of West Antarctica

“…HEW remains consistent with the stratigraphic interpretation of the position of the EWM north of the Pensacola Mountains (Schopf, 1969) and is consistent with mineralogical and paleontological provenance studies suggesting the Ellsworth Mountains sediments were sourced from the Transantarctic region of East Antarctica (Elliot et al, 2016;Stone and Thompson, 2005). The motion of the HEW in this less far travelled model would be consistent with either the proposed two stage, or more complex single stage tectonic models for the evolution of the WSRS magnetic lineations (Figs.…”

“…8). We infer that this free edge was most likely associated with a subduction system, given the presence in the Permian of a magmatic arc proximal to the EWM (Elliot et al, 2016), and the extensive Middle to Upper Jurassic Latady back-arc basin along the eastern edge of the Antarctic Peninsula (Laudon, 1992). Within the…”

“…1) (Elliot et al, 2016). The earliest Paleozoic sequences record sedimentation and volcanism ~512 Ma in an inferred continental rift setting (Curtis, 2001) approximately coeval with the EAAO and Ross orogens (Fig.…”

“…1) were deposited in a basin distinct from the South African Karoo basin, with material dominantly sourced from East Antarctica (Elliot et al, 2016). Stratigraphic correlation, including the presence of extensive Permo-Carboniferous glacial tills in the EWM and Pensacola Mountains (Matsch and Ojakangas, 1992 ;Schopf, 1969) has been used to constrain the EWM to a position north of the present day Pensacola Mountains (Schopf, 1969).…”

An Early Permian, paleopolar, postglacial, river-dominated deltaic succession in the Mackellar–Fairchild formations at Turnabout Ridge, Central Transantarctic Mountains, Antarctica

“…3) with a trend similar to that of the modern Transantarctic Mountains (Fig. 3B) (Lindsay, 1970;Elliot, 1975;Barrett, 1986Elliot et al, 2014). This intracratonic basin formed prior to the formation of a retroarc foreland basin that developed due to subduction, magmatic arc development, and crustal loading by thrust sheets along the Panthalassan margin (Fig.…”