How Continents Break-up and New Ocean Ridges are Established

The processes that lead to the transition from continental extension and break-up to steady-state mid-ocean ridge formation are not well understood. Particular unknowns are the paleo-water depths at which the continental lithosphere breaks up, the nature of the crust at the so-called continent-ocean transition and when and how a steady-state mid-ocean ridge is established. To understand these questions we use numerical models that couple tectonic deformation, sedimentation, hydrothermal cooling, serpentinisation and melting, as a virtual laboratory. We present results of models run with different velocities that simulate natural examples observed in nature such as the South China sea and the West Iberia-Newfoundland margins. We focus on the evolution of subsidence, heat-flow and nature of the basement as the rift transforms into a steady-state mid-ocean ridge and show how the interplay between tectonics and hydrothermal cooling lead to the different configurations observed in nature.