Reconstruction of a Ross lost Cambrian<i>Series 2</i>mixed siliciclastic–carbonate platform from carbonate clasts of the Shackleton Range, Antarctica

ABSTRACT The presence of archaeocyath-bearing clasts from Cenozoic tills and Cambrian Mount Wegener Formation reveal erosion a hidden carbonate platform in Shackleton Range, Antarctica. We provide microfacies, paleontological, diagenetic tectonically induced fabric data which, addition to available geochemical geochronological allow the paleoenvironmental reconstruction lost Series 2 mixed siliciclastic–carbonate that was developed eroded during Ross orogeny. Carbonate production dominated by non-skeletal grains possibly restricted platform-interior oolitic shoal complex settings, while open subtidal sub-environments (calcimicrobe carpets, calcimicrobe–archaeocyath patch reefs, muddy bottoms) were diverse calcimicrobe assemblage and/or secondary accessory heterozoan (archaeocyaths other sponges, chancelloriids, hyoliths, coralomorphs, trilobites, echinoderms). describe Botoman with 34 archaeocyathan species among 12 existing genera. A new archaeocyath family Shackletoncyathidae is proposed. New ( Rotundocyathus glacius sp. nov., Buggischicyathus microporus gen. et Paragnaltacyathus hoeflei , Shackletoncyathus buggischi et. Santelmocyathus santelmoi Wegenercyathus sexangulae nov.) Tabulaconus kordae coralomorph are reported Antarctica for first time. Archaeocyathan fauna share few contemporary South Australia (9) even fewer Antarctic platforms Limestone (2) or Schneider Hills limestone (1). Similarity greater allochthonous assemblages Permo-Carboniferous tillites Ellsworth Mountains (2), deposits King George Island (4) Weddell Sea Range lost/hidden shows distinct entity related its tectonosedimentary evolution, possible back-arc basin on Mozambique seaway E W Gondwana amalgamation, which distinguishes it those palaeo-Pacific margin craton.