Dynamics of lithospheric thinning and mantle melting by edge‐driven convection: Application to Moroccan Atlas mountains

摘要: Edge-driven convection (EDC) forms in the upper mantle at locations of lithosphere thickness gradients, e.g., craton edges. In this study we show how traditional style EDC, a cell governed by cold downwelling below an edge alternates with another which as secondary feature hot asthenospheric shear flow from underneath thicker lithosphere. These alternating EDC styles produce episodic erosion and decompression melting. Three-dimensional models that rolls form perpendicular to gradient lithosphere-asthenosphere boundary. Stagnant-lid scaling laws are used gain further insight underlying physical processes. Application our Moroccan Atlas mountains region shows combination these two can reproduce many observations mountains, including distinct periods Cenozoic volcanism, semicontinuous corridor thinned under piecewise delamination A very good match between numerical is found for thicknesses across area, amounts melts produced, length quiet gap volcanic episodes quantitative observations.