Aug CIG Magma Dynamics Workshop Basic Ingredients for a useful theory of magma dynamics

Aug CIG Magma Dynamics Workshop A basic recipe for a theory of Magma Dynamics Requires: At least 2 phases (include both melt and solid) Significant mass-transfer between phases (melting/reaction/crystallization/thermodynamics) The system must be permeable at some scale to allow melts to move. The system must be deformable (consistency with mantle convection and lithospheric deformation) Considers chemical transport in open systems –Passive tracers –Reactive components

Aug CIG Magma Dynamics Workshop Coupled Fluid-Solid Mechanics Problems to consider The “dry problem” (no fluids) Permeable flow in viscous media (magma migration in the convecting mantle) Brittle flow in the crust and lithosphere (diking) Disaggregation and the transition to Diking (Mushes?) Fundamental Issues: Appropriate rheologies for coupled fluid-solid systems Consistent solid stress and fluid pressure.

Aug CIG Magma Dynamics Workshop Melting Models Problems to consider Forced Adiabatic melting Simplified Reactive Systems Simplified Thermodynamics/Phase Diagrams Fully coupled Thermodynamics/Geodynamics Role of H20/Volatiles Fundamental issues: # Phases/Components/Equations of state? Uncertainty in thermodynamic models What is the correct Pressure?

Aug CIG Magma Dynamics Workshop Comparing Models to Observations ( & Experiment) Problems to consider Geochemistry/Petrology –Trace element Geochemistry –Short and long-lived radio nuclides (e.g. U-series) –Major element chemistry/petrology Geophysics –Seismology, Seismicity, Gravity, E&M Geology –Volume/Geometry/Organization/(History) of magmatic systems and plate boundaries Fundamental issues: Partition Coefficients/Diffusivities/Dispersivities for tracers Material properties (elastic moduli, conductivity, density) of partially molten materials Computational seismology and synthetic seismograms Interfacing with Data Bases (bathymetry, chemistry, seismology, seismicity…)