PT  - JOURNAL ARTICLE
AU  - Ghosh, Attreyee
AU  - Holt, William E.
TI  - Plate Motions and Stresses from Global Dynamic Models
AID  - 10.1126/science.1214209
DP  - 2012 Feb 17
TA  - Science
PG  - 838--843
VI  - 335
IP  - 6070
4099  - http://science.sciencemag.org/content/335/6070/838.short
4100  - http://science.sciencemag.org/content/335/6070/838.full
SO  - Science2012 Feb 17; 335
AB  - Delineating the driving forces behind plate motions is important for understanding the processes that have shaped Earth throughout its history. However, the accurate prediction of plate motions, boundary-zone deformation, rigidity, and stresses remains a difficult frontier in numerical modeling. We present a global dynamic model that produces a good fit to such parameters by accounting for lateral viscosity variations in the top 200 kilometers of Earth, together with forces associated with topography and lithosphere structure, as well as coupling with mantle flow. The relative importance of shallow structure versus deeper mantle flow varies over Earth’s surface. Our model reveals where mantle flow contributes toward driving or resisting plate motions. Furthermore, subducted slabs need not act as strong stress guides to satisfy global observations of plate motions and stress.