GSA 2020 Connects Online

Paper No. 95-5
Presentation Time: 7:05 PM

CAN SUPERCONTINENTS FORM WITHOUT PLATE TECTONICS?


CZECH, Theresa L., Washington State University, School of the Environment, Pullman, WA 99163 and COOPER, Catherine M., Washington State University, School of the Environment, Pullman, WA 99164

Plate tectonics with deep subduction is believed to be how Earth formed supercontinents about 3 billion years ago. However, geologic evidence for this theory is limited so we have used geologic and physics constraints to explore the option of supercontinent cycles occurring within stagnant lid convection. Our model uses time dependent 2D models to model motion between continents embedded within stagnant lid convection. If it is possible to drive plate motion without strong subduction then that would change how we view the interaction between the mantle and continents in a young Earth. The topic of when plate tectonics began on Earth is still greatly debated and finding that the first supercontinents are not definitive evidence for this could change how we view the beginning of this unique process. Our models have shown that it is possible for the continents to move from convective stresses enough to form a supercontinent without strong subduction.