RT Journal Article
SR Electronic
T1 Plate Motions and Stresses from Global Dynamic Models
JF Science
JO Science
FD American Association for the Advancement of Science
SP 838
OP 843
DO 10.1126/science.1214209
VO 335
IS 6070
A1 Ghosh, Attreyee
A1 Holt, William E.
YR 2012
UL http://science.sciencemag.org/content/335/6070/838.abstract
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.