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• #Singlecrystal 2 simulate synchrotron free#

Deformed, single crystal halite was annealed inside a scanning electron microscope at temperatures between 280-470 ✬. The dynamics of substructures, which encompass all structures present at the subgrain-scale, were investigated by static, in-situ annealing experiments. 982-996 Article in journal (Refereed) Published Abstract , De Geersalen, Geovetenskapens hus, Svante Arrhenius väg 14, Stockholm, 10:30 (English)Ģ010 (English) In: Journal of Structural Geology, ISSN 0191-8141, E-ISSN 1873-1201, Vol. Halite, in-situ, X-ray diffraction, EBSD, annealing, substructure, modelling National CategoryĮarth and Related Environmental Sciences Research subject Geology Identifiers URN: urn:nbn:se:su:diva-45811 ISBN: 978-91-7447-187-8 (print) OAI: oai::su-45811 DiVA, id: diva2:369878 Public defence Meddelanden från Stockholms universitets institution för geologiska vetenskaper 342 Keywords Place, publisher, year, edition, pagesStockholm: Department of Geological Sciences, Stockholm University, 2010. While relative boundary mobilities will be similar, absolute values must therefore be treated with some care when using a 2D analysis. This difference is interpreted to be related to boundary drag on thermal grooves on the 2D experimental surface. Boundary migration, however, occurred more extensively in the 3D experiment.

#Singlecrystal 2 simulate synchrotron free#

Comparison of 2D experiments to 3D indicated that general boundary behaviour was similar within the volume and was not significantly influenced by effects from the free surface. Dislocations were found to remain independent to much higher misorientation angles than previously thought, with simulation results indicating that change in boundary response occurs at ~7º for halite. Numerical simulation of the recovery process supported these findings, with much of the subgrain boundary behaviour reproduced with small variation to the mobilities on different rotation axes and increase of the size of the calculation area to imitate long-range dislocation effects. Subgrain boundaries were categorised with regard to their behaviour during annealing, orientation and morphology and it was found that different types of boundaries have different behaviour and must be treated as such. Behaviour is highly dependent on the temperature of annealing, particularly related to the activation temperature of climb and is also strongly reliant on short versus long range dislocation effects. The main outcome of the project is a significantly refined model for recovery at annealing temperatures below that of deformation preceding annealing. The study combines three different techniques in-situ annealing experiments conducted inside the scanning electron microscope and coupled with electron backscatter diffraction, 3D X-ray diffraction coupled with in-situ heating conducted at the European Radiation Synchrotron Facility and numerical simulation using the microstructural modelling platform Elle. This project details an in-depth study of substructural dynamics during post-deformational annealing, using single-crystal halite as an analogue for silicate materials. The substructure governs the rheology of a rock, which in turn determines how it will respond to different processes during tectonic changes. Substructure dynamics incorporate all features occurring on a subgrain-scale. 2010 (English) Doctoral thesis, comprehensive summary (Other academic) Abstract