Crust-Lithosphere-Asthenosphere Interplay, Deformation and Dynamics
Knowledge of the lithosphere-asthenosphere system and its dynamics is one of the key questions for understanding geological processes. Constraints on the style, mechanism, and pattern of deformation in the crust and upper mantle come from direct and indirect observations using a variety of methods. Seismological studies focusing on anisotropy have successfully improved our knowledge of deformation patterns, and when combined with tomographic models, anisotropy can shed light on the geometry of deformation in the lithosphere and asthenosphere. Sophisticated geodynamic modeling (numerical and physical analogue) and laboratory (rock physics) experiments enhance our understanding of flow patterns in the Earth’s upper mantle and their bearing on vertical motions of crust and lithosphere. Combined with seismic anisotropy data these methods have the potential to reveal the mechanisms that create deformation-induced features such as shape preferred orientation (SPO) and lattice-preferred orientation (LPO). Structural and kinematic characterization of deformation events by geometric and kinematic analyses infer the direction and magnitude of the tectonic forces involved in driving deformation within crust and upper mantle. Additionally, physical analogue and numerical modeling studies have fostered our understanding of complex 3D-plate interaction on various time-scales, regulated through the degree of plate coupling and the rheology of the lithosphere.
However, more work is required to better integrate the various experimental and modelling techniques and to link them to multi-scale observations. This session will bring together different disciplines that focus on the deformation of the lithosphere and upper mantle as well as on the dynamics and nature of the lithosphere-asthenosphere system. The main goal is to demonstrate the potential of different methods, and to share ideas of how we can collaboratively study lithospheric deformation, and how it relates to the ongoing dynamics within the asthenospheric mantle. Contributions are sought from studies employing seismic observation, geodynamical modeling (analogue and numerical), structural geology, and mineral and rock physics.
Greg Houseman (Institute of Geophysics and Tectonics, University of Leeds)
Agnes Kiraly (Department of Geosciences, University of Oslo)