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Using Open Sidewalls for Modelling Self-consistent Lithosphere Subduction Dynamics : Volume 4, Issue 1 (18/06/2012)

By Chertova, M.

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Book Id: WPLBN0004021854
Format Type: PDF Article :
File Size: Pages 38
Reproduction Date: 2015

Title: Using Open Sidewalls for Modelling Self-consistent Lithosphere Subduction Dynamics : Volume 4, Issue 1 (18/06/2012)  
Author: Chertova, M.
Volume: Vol. 4, Issue 1
Language: English
Subject: Science, Solid, Earth
Collections: Periodicals: Journal and Magazine Collection, Copernicus GmbH
Historic
Publication Date:
2012
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications

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Den Berg, A. V., Geenen, T., Spakman, W., & Chertova, M. (2012). Using Open Sidewalls for Modelling Self-consistent Lithosphere Subduction Dynamics : Volume 4, Issue 1 (18/06/2012). Retrieved from http://kindle.worldlibrary.net/


Description
Description: Utrecht University, Utrecht, The Netherlands. Subduction modelling in regional model domains, in 2-D or 3-D, is commonly done using closed, vertical boundaries. In this paper we investigate the merits of using open boundaries for 2-D modelling of lithosphere subduction but with implication for 3-D modelling. Open sidewalls allow for lateral in- and outflow consistent with the internal dynamics of the model and may simulate the real-mantle environment of subduction much better than closed boundaries, which induce return flows. Our experiments are focused on using open and closed (free-slip) sidewalls while comparing results for two model aspect ratios of 3:1 and 6:1. Slab buoyancy driven subduction with open boundaries immediately develops into strong rollback with high trench retreat velocities. Mantle asthenosphere flow forced by rollback is predominantly laminar and facilitated by the open boundaries. In contrast, free-slip sidewalls proof restrictive on subduction rollback evolution unless the lithosphere plates are allowed to move away from the sidewalls. This, however, initiates return flows pushing both plates toward the subduction zone speeding up subduction. Increasing the aspect ratio to 6:1 does not change the overall flow pattern when using open sidewalls. Again, in contrast, for free-slip boundaries, the slab evolution does change with respect to the 3:1 aspect ratio and does not resemble the 6:1 evolution obtained with open boundaries. We notice a general drop in the amplitude of mantle flow when changing to the 6:1 aspect ratio, which is caused by the increasing shear friction between mantle and lithosphere while the driving slab buoyancy is the same. Based on energy-dissipation arguments we applied a flow speed scaling to convert between flow fields of different model aspect ratios. This proved succesful for the open boundary model. We have also investigated the effect of far-field stress conditions in our open boundary models. Applying realistic normal stress conditions to the strong part of the overriding plate we show that intra-plate stresses control subduction dynamics resulting in slab roll-back, stationary or advancing subduction. We conclude that open boundaries are to be preferred for modelling subduction evolution (rollback, stationary or advancing). The relative independence of model aspect ratio avoids the need to place sidewalls at large distance and allows to focus all computational resources on a smaller modelling domain. Open boundaries simulate the natural subduction environment better and avoid the adverse effects (e.g. forced return flows) of free-slip boundaries.

Summary
Using open sidewalls for modelling self-consistent lithosphere subduction dynamics

Excerpt
Babeyko, A. Y. and Sobolev, S. V.: High-resolution numerical modelling of stress distribution in visco-elasto-plastic subducting slabs, Lithos, 103, 205–216, 2008.; Baes, M., Govers, R., and Wortel, R.: Subduction initiation along the inherited weakness zone at the edge of a slab: Insights from numerical models, Geophys. J. Int., 184, 991–1008, 2008.; Behounkova, M. and Cizkova, H.: Long-wavelength character of subducted slabs in the lower mantle, Earth Planet. Sci. Lett., 275, 43–53, 2010.; Billen, M. I. and Gurnis, M.: Comparison of dynamic flow models for the Central Aleutian and Tonga-Kermadec subduction zones, Geochem. Geophys, Geosyst, 4, 17 pp., doi:10.1029/2001GC000295, 2003.; Billen, M. I.: Slab dynamics in the transition zone, Phys. Earth Planet. Int., 25, 297–356, 2010.; Burgmann R. and Dresen G.: Rheology of the lower crust and upper mantle: evidence from rock mechanics, geodesy and field observations, Ann. Rev. Earth Planet. Sci., 36, 531–536, 2008.; Capitanio, F. A., Stegman, D. R., Moresi, L. N., and Sharples, W.: Upper plate controls on deep subduction,trench migration and deformations at convergent margins, Tectonophysics, 483, 80–92, 2010.; Cristensen, U. R. and Yuen, D. A.: Layered convection indiced by phase transition, J. Geophys. Res., 99, 10291–10300, 1985.; Cizkova, H., van den Berg, A. P., Spakman, W., and Matyska, C.: The viscosity of Earth's lower mantle inferred from sinking speed of subducted lithosphere, Phys. Earth Planet. Int., in press., 2012.; Cizkova, H., van Hunen, J., van den Berg, A. P.: Stress distribution within subducting slabs and their deformation in the transition zone, Phys. Earth Planet. Int., 161, 202–214, 2007.; Enns, A., Becker, T. W., and Schmeling, H.: The dynamics of subduction and trench migration for viscosity stratification, Geophys. J. Int., 160, 761–775, 2005.; Funiciello, F., Faccenna, C., Giardini, D., and Regenauer-Libeb, K.: Dynamics of retreating slabs: Insights from three-dimensional laboratory experiments, J. Geophys. Res., 108, 16 pp., doi:10.1029/2001JB000896, 2003.; Funiciello, F., Faccenna, C., Heuret, A., Lallemand, S., Giuseppe, E. Di., and Becker, T. W.: Trench migration, net rotation and slab-mantle coupling, Earth Planet. Sci. Lett., 271, 233–240, 2008.; Gerya, T.: Future directions in subduction modelling, J. Geodynam., 52, 344–378, 2011.; Han, L. and Gurnis, M.: How valid are dynamic models of subduction and convection when plate motion are prescribed? Physics of the Earth and planetary interiors, 110, 235–246, 1999.; Jadamec, M. A. and Billen, M. I.: Reconciling surface plate motions with rapid three-dimensional mantle flow around a slab edge, Nat. Lett., 465, 338–342, 2010.; Jadamec, M. A. and Billen, M. I.: The role of rheology and slab shape on rapid mantle flow: Three-dimensional numerical models of the Alaska slab edge, J. Geophys. Res., 117(B2), 20 pp., doi:10.1029/2011JB008563, 2012.; Karato, S., Rubie, D., and Hong Yan, S.: Dislocation recovery in olivine under deep upper mantle conditions: implication for creep and diffusion, J. Geophys. Res., 98, 9761–9768, 1993.; Karato, S., Riedel, M., and Yuen, D. A.: Rheological structure and deformation of subducted slabs in mantle transition zone: implications for mantle circulation and deep earthquakes, Phys. Earth Planet. Int., 127, 83–108, 2001.; Kaufmann, G. and Lambek, K.: Mantle dynamics, postglacial rebound and the radial viscosity profile, Phys. Earth Planet. Int., 121, 301–324, 2000.; Lithgow-Bertelloni, C. and Guynn, J. H.: Origin of the lithospheric stress field, J. Geophys. Res., 109, 32 pp., doi:10.1029/2003JB002467, 2004.; Manea, V. and Gurnis, M.: Subduction zone evolution and low-viscosity wedges and channels, Earth Planet. Sci. Lett., 264, 22-45, 2007.; Ozbench, M., Regenauer-Lieb, K., Stegman, D., Morra, G., Farrington, R., Hale, A., May, D. A., Freeman, J., Bourgouin, L., Muhlhaus, H., and Moresi, L.: A model comparison study of large-scale mantle-

 

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