Scaling Laws for Mixed Heated Convection With Pseudoplastic Rheology: Implications for the Bistability of Tectonic Mode

Plate tectonics is a tectonic style thought to be the hallmark of habitable planets, and yet the inherent complexities of plate tectonic convection have clouded the establishment of simple scaling laws with which to model convective behavior and thermal evolution. We have recently developed a scaling approach for mixed heated convection, based upon several simple physical principles. Here, we generalize our scaling approach to mixed heated convection with pseudoplastic rheology, which gives rise to the plate tectonic mode of convection. We then apply our scaling results to the so-called bistability of tectonic mode. By illustrating common pitfalls regarding heating mode and nondimensionalization, we demonstrate that tectonic mode is unique with respect to key planetary properties, and that a convective regime diagram for terrestrial planets is within reach.