Quantifying the net slab pull force as a driving mechanism for plate tectonics

It has remained unclear how much of the negative buoyancy force of the slab ( F B ) is used to pull the trailing plate at the surface into the mantle. Here I present three‐dimensional laboratory experiments to quantify the net slab pull force ( F NSP ) with respect to F B during subduction. Results show that F NSP increases with increasing slab length and dip up to ∼8–12% of F B , making F NSP up to twice as large as the ridge push force. The remainder of F B is primarily used to drive rollback‐induced mantle flow (∼70%), to bend the subducting plate at the trench (∼15–30%) and to overcome shear resistance between slab and mantle (0–8%).