Quantitative structural analyses and numerical modelling of ...

Foreword 32008, 2007) and subsequently applied to describe evolution of orogenic root in BohemianMassif. Here we used available geochemical and geochronological data to argue that thefelsic lower crust is an allochthonous body emplaced underneath pre-existing mafic lowercrust during continental subduction (Schulmann et al., 2009b). Similar scenario was recentlyproposed for evolution Orlica-Śnieżnik dome in Western Sudetes (Chopin et al.,2011a). It appears that influx of crustal material to the orogenic root zone have a majorimpact on his future thermal and rheological evolution. Detailed study of geodynamicconsequences caused by subduction of felsic and radioactively productive material underthe orogenic system is described in Lexa et al. (2011) and this aspect will be furtherelaborated in the chapter “Perspectives for the thermomechanical modelling of channelflow in the orogeny”.The last topic “Quantitative analysis of metamorphic microstructures, its visualizationand statistical description” introduce a comprehensive set of quantitative methodsfor analysis of deformation microstructures and it is based on PolyLX software developedby myself. This chapter will deal with techniques of microstructure digitalization andsubsequent statistical processing, including evaluation of the grain size, grain shapes andstatistics of their mutual contacts. The PolyLX covers several methods of quantificationof preferred orientation of grains and boundaries as well as their statistical processing.This method allows us not only visualize microstructure characteristics and their statisticaltreatment, but also address some kinetic problems of metamorphic microstructures.This method was originally described in my Ph.D. thesis and firstly applied in the workof Lexa et al. (2005). Subsequently, the PolyLX software was successfully used in numerouspublications of our research group (Baratoux et al., 2005a,b, Hasalová et al., 2008a,Jeřábek et al., 2007, Kratinová et al., 2010, Lexa et al., 2005, Machek et al., 2007, Schulmannet al., 2008b, Závada et al., 2007, 2009). In addition, there is a number of laboratoriesin France, where I worked during my post-doctoral fellowship and I led specializedcourses in this subject, which are routinely using PolyLX software in complex microstructuralproblems (Barraud, 2006, Chopin et al., 2011b, Martelat et al., 2011, Oliot et al.,2011). It appears, that PolyLX becomes valuable tool for projects, where quantificationof the spatial relationships of minerals is needed. Recently I leed three specialized workshops(Granulites & Granulites 2009, Prague; 2010 Tromsø; Geomaterials 2011, Prague)focused on quantitative microstructure analyses. Recently, PolyLX has interfaces toexchange data with softwares like ELLE (http://www.materialsknowledge.org/elle) orMTEX (http://code.google.com/p/mtex) that allows simulating the evolution of deformationmicrostructures or quantitative textural analyses of natural samples. Futherideas as some of the new kinetic and petrogenetic outputs that could be depicted bythis method (Franěk et al., 2011b) are given in the chapter “Perspectives for numericalmodelling of deformation microstructures and their quantification”. As PolyLX is open