Duretz Thibault, Gerya T. V., Kaus B. J. P., Anderson T. B. (2012), Thermomechanical modeling of slab eduction, in
Journal of Geophysical Research, 117(B8), B08411.
Duretz Thibault, Schmalholz S. M., Gerya T. V. (2012), Dynamics of slab detachment, in
Geochemistry Geophysics Geosystems, 13(3), Q03020.
Crameri Fabio, Tackley P.J., Meilick I., Gerya T. V., Kaus B. J. P. (2012), A free plate surface and weak oceanic crust produce single-sided subduction on Earth, in
Geophysical Research Letters, 39(3), L03306.
Crameri Fabio, Schmeling H., Golabek G. J., Duretz T., Orendt R., Buiter S. J. H., May D. A., Kaus B. J. P., Gerya T. V., Tackley P. J. (2012), A comparison of numerical surface topography calculations in geodynamic modelling: an evaluation of the ‘sticky air’ method, in
Geophysical Journal International, 189(1), 38-54.
Duretz Thibault, Gerya Taras, Slab detachment during continental collision: Influence of crustal rheology and interaction with lithospheric delamination, in
Tectonophysics, in press.
We are presently performing an SNF-funded research project that is part of the larger TOPO-4D project “Mantle forcing of Earth surface evolution in Europe and the Mediterranean: From Past to Present”, an international Collaborative Research Project (CRP) awarded under the European TOPO-Europe Eurocores program. Our project is one of 6 Independent Projects (IPs) in TOPO-4D, the other ones involving teams in Oslo, Utrecht (2), Rome and Bochum. Our IP, funded by SNF, involves two sub-projects, each performed by a Ph.D. student. The first study focusses on regional models of subduction, identifying the response of surface topography to the evolution of subduction-collision zones, in particular to slab breakoff. The second study focusses on global models of convection and plate tectonics that include subduction, characterising in a general way the interaction between surface topography and changes in subduction and mantle convection, then using this to interpret specific observations. Both sub-studies have already obtained interesting results, giving a detailed understanding of the mechanisms that lead to slab breakoff and the resulting topographic response, and showing that a correct treatment of surface topography (i.e. a free surface) is essential for realistic subduction zones to arise in models. These results have been presented at international conferences and have resulted in at least one submitted or published paper per study. Here we request funds to allow the two students an additional 6 months and 12 months respectively. The 12 months extension is requested because the student presently only has 25 months (too short to finish a PhD) of funding due to an earlier student, and the 6 months is requested to allow that student to capitalise on his progress, fully finish the sub-studies that he has started and complete two papers more than he would with the present end date. The additional 6 months for the regional study (topographic response to slab breakoff) would facilitate the completion of a systematic 3-D study (the results so far are in 2-D). The 3-D model is available, but there will not be time for a systematic study with the present ending date. It would also facilitate the completion of a technical advance: nonlinear Newton iterations, which would greatly help this and future modelling efforts. The 12 months extension for the global study would facilitate a systematic study in 3-D spherical geometry of self-consistent plate tectonics and mantle convection with both continental and oceanic plates, which is really needed to answer the questions originally posed and to allow the student to complete a full 3 years of PhD research.