Ocean-continent subduction cannot be initiated without preceding intra-oceanic subduction!

The formation of new subduction zones is a key element plate tectonics and the Wilson cycle, many different controlling mechanisms have been proposed to initiate subduction. Here, we provide brief overview known scenarios initiation in intra-oceanic ocean-continent tectonic settings. Intra-oceanic most commonly associated with mechanical heterogeneities within oceanic lithosphere, such as pre-existing fracture zones, spreading ridges, transform faults. Numerous well-recognized examples active formed environments during Cenozoic, suggesting that ocean-ocean must be routine process occurs “easily frequently” mode currently operating on Earth. On contrary, traditional for establishment classic self-sustaining subduction—passive margin collapse transference—are surprisingly rare observations difficult reproduce numerical models. Two alternative scenarios—polarity reversal lateral propagation-induced initiation—are contrast much better documented nature experimentally. However, switching polarity due arc-continent collision transmission subducting boundaries are both inextricably linked convergence. We, therefore, conclude onset possible only through transition from former system. This likely facilitated by ductile damage accumulation stress concentration across aging continental margin. From this perspective, future closure Atlantic Ocean can viewed an archetypal example role transitional between (Lesser Antilles) development zone at passive (eastern North America).