Subduction‐Induced Back‐Arc Extension Versus Far‐Field Stretching: Contrasting Modes for Continental Marginal Break‐Up

Continental break-up is an ingredient of plate tectonics and the Wilson cycle. During evolution Tethyan Realm since Paleozoic, a series ribbon-like (micro-)continents are split from Gondwana drifted northwards to Eurasian continent. The initial opening Neo-Tethys Ocean follows typical continental marginal Cimmeria Gondwana, which generally considered be driven by subduction Paleo-Tethyan plate. Yet, competition between back-arc extension far-field stretching matter long-standing debate. Therefore, authors here present results systematic 2-D numerical simulations. reveal four types subduction-induced break-ups: extension, stretching, double break-up, channel opening. A weak relic suture zone prerequisite for important factor controlling mode selection. occurs relatively short shallow dipping highly viscous subducted slabs. mode, on other hand, preferably spatially long wide slabs without mid-ocean ridges. Combining geological observations, simulations force balance analyses, propose that northward, single-sided Paleo-Tethys oceanic beneath Laurasia, was most likely responsible Cimmerian terranes Gondwana. This would have required both pre-existing zones already ridge, thus played role in Ocean.