Destruction of Cratonic Lithosphere Induced by Oceanic Subduction Initiation

Abstract

AbstractBased on the plate reconstruction which shows that most core parts of present cratons locate in the interior of the continents during the supercontinent cycles, we propose that the oceanic subduction initiation may trigger the destruction of marginal cratonic lithosphere. We develop a simplified force analysis for the destruction of subcontinental lithospheric mantle (SCLM) by the subduction initiation. Our analysis suggests three key parameters: the SCLM thickness, the contact angle between SCLM and oceanic plate, and the coefficient of friction of the SCLM. Our numerical models further support our analysis and demonstrate that a thicker SCLM with a larger contact angle is easier to be destructed by subduction initiation, and the yield strength of the SCLM has a significant impact on the spatial range of its destruction. Our results provide important insights into the parameters controlling cratonic lithospheric destruction and explain the distribution of preserved cratons in the interior of continental plates.