Geodynamic processes are generally too slow, too rare or too deep to be observed in situ. Understandably, simulation has become an integral part of the Earth explorer's toolbox to select, formulate and test hypotheses on the origin and evolution of geodynamic processes. However, experimental and computer simulations using analogue and numerical models, respectively, have evolved rather separately and independently, often without much interaction of the respective communities. Only in recent years, efforts have been made to combine the two simulation techniques and to investigate in more detail approach-inherent advantages and disadvantages.

Numerical models (e.g., finite element, discrete element, finite differences) are inherently deterministic, precisely controllable and allow for a wide parameter space to be mapped, but suffer from space-time discretization limited by computer power or code-controlled artifacts. In contrast, analogue models are real physical objects subjected to the same laws (and flaws) of nature as the Earth, including the time-space continuum and randomness, but they are limited in parameter space, less controllable and similarly dependent on experimentalist performance and laboratory boundary conditions. Both numerical and analogue simulations yield results that compare favorably with geological structures in nature. However, it is often uncertain and in many cases a question of faith rather than a well-reflected position, whether necessary model simplifications are appropriate, mathematical descriptions accurate or upscaling of laboratory observations meaningful.

In order to foster communication and interaction between the experimental and computer simulation communities, we invite contributions demonstrating the state-of-the-art in analogue and numerical tectonic modeling on a variety of spatial and temporal scales, from earthquake nucleation to plate tectonics. We welcome especially those papers that try to highlight strengths, challenge the limits or compare/combine the different approaches in order to realistically simulate and better understand the Earth's deformational behavior.

This session is a result of a merge between four sessions:
TS9.1: Recent advances in analogue and numerical modeling of tectonic processes
TS3.2: Exploring field and experimental data with the numerical lens
TS9.2: How can numerical and analogue experiments validate our interpretations of orogenesis
TS9.3: Application of the Discrete Element Method (DEM) in the geosciences

Solicited speaker:
Michele Cooke: Evolving mechanical efficiency of restraining bends (with A. Hatem, O. Difo)
Susanne Grigull: Quartz rheology from field observations and numerical modelling (with S.M. Ellis, T.A. Little, M.P. Hill, S.J.H. Buiter)
Marta Adamuszek: Estimation of rheological parameters from the geometry of a single-layer fold train (with M. Dabrowski, D.W. Schmid)