In this section
@article{Fourel:2014:10.1002/2014GC005535,
author = {Fourel, L and Goes, S and Morra, G},
doi = {10.1002/2014GC005535},
journal = {Geochemistry, Geophysics, Geosystems},
pages = {4507--4525},
title = {The role of elasticity in slab bending},
url = {http://dx.doi.org/10.1002/2014GC005535},
volume = {15},
year = {2014}
}
TY - JOUR
AB - Previous studies showed that plate rheology exerts a dominant control on the shape and velocity of subducting plates. Here, we perform a systematic investigation of the role of elasticity in slab bending, using fully dynamic 2-D models where an elastic, viscoelastic, or viscoelastoplastic plate subducts freely into a purely viscous mantle. We derive a scaling relationship between the bending radius of viscoelastic slabs and the Deborah number, De, which is the ratio of Maxwell time over deformation time. We show that De controls the ratio of elastically stored energy over viscously dissipated energy and find that at inline image, substantially less energy is required to bend a viscoelastic slab to the same shape as a purely viscous slab with the same intrinsic viscosity. Elastically stored energy at higher De favors retreating modes of subduction via unbending, while trench advance only occurs for some cases with inline image. We estimate the apparent Deborah numbers of natural subduction zones and find values ranging from inline image to > 1, where most zones have low inline image, but a few young plates have De > 0.1. Slabs with inline image either have very low viscosities or they may be yielding, in which case our De estimates may be underestimated by up to an order of magnitude, potentially pointing towards a significant role of elasticity in inline image of the subduction zones. In support of such a role of elasticity in subduction, we find that increasing De correlates with increasing proportion of larger seismic events in both instrumental and historic catalogues.
AU - Fourel,L
AU - Goes,S
AU - Morra,G
DO - 10.1002/2014GC005535
EP - 4525
PY - 2014///
SN - 1525-2027
SP - 4507
TI - The role of elasticity in slab bending
T2 - Geochemistry, Geophysics, Geosystems
UR - http://dx.doi.org/10.1002/2014GC005535
UR - http://onlinelibrary.wiley.com/doi/10.1002/2014GC005535/abstract
UR - http://hdl.handle.net/10044/1/18566
VL - 15
ER -