Ordovician orogeny in the Alps: a reappraisal

摘要: An important part of the pre-Mesozoic basement Alps is product orogenic processes occurred in Ordovician times. Most geological constrains for this reconstruction have been obtained by study Strona-Ceneri zone Southern Alps, where Alpine overprint was weak. The erosion late Pan-African belts delivered large amounts greywackes and pelites into subduction zones along Gondwana. sediments were subducted accreted to form wide complexes. As a result sediment input, retreated mantle-derived magmas intruded base fertile “mud pile.” This initiated substantial anatexis produce peraluminous magmas, which extruded syntectonically. Thereby, predominantly steeply structured subduction–accretion complex provided ideal pathways uprising down-thrusting host rocks an isostatically stable crust. SE Australian Lachlan fold belt interpreted as upper crustal analog zone. Based on combination their geology, profile through Alaskan type orogen drawn.