Application of the time-dependent boundary conditions for convergence velocity for modelling of ophiolite obduction

Abstract

2D numerical geodynamic modelling applied in this paper gives a better insight into the process of obduction of two distinct ophiolite belts during the closure of a single ocean. Closure of the ocean is achieved by imposed convergence of the tectonic plates. In the created numerical themomechanical models, the influence of the variable velocity of the tectonic plate motions is analyzed. Convergence rate variation is modelled with the goal of achieving obduction and the permanent emplacement of ophiolites via complex evolution of the plate velocities. The basis of the model is the closure of an ocean through a flat intra-oceanic subduction, during which the plates change intensity and direction of their motion. Divergent phase of the evolution leads to the short-lived spreading of the new oceanic domain in from which, after the final closure, one of the two ophiolite belts originates.

Keywords

• geodynamics
• numerical modelling
• obduction
• boundary conditions