GD7.1/EMR12/GMPV18/SM4.6 Structure, Composition and Dynamics of the Deep Earth (co-organized)

Convener: Jon Mound  | Co-Convener: Michael Ammann

Oral Programme  / Fri, 08 Apr, 13:30–17:00  / Room 22 Poster Programme  / Attendance Thu, 07 Apr, 17:30–19:00  / Display Thu, 07 Apr, 08:00–19:30  / Hall A

Improved seismic observations have revealed increasingly detailed pictures of the Earth's deep interior, which provide new constraints and challenges for geodynamic models of the core and lower mantle. Within the inner core both radial and hemispheric variations in seismic wave speed and anisotropy have been detected and mapped. Within the outer core there has been conflicting evidence both for and against the existence of stratified layers at the inner-core and core-mantle boundaries. Within the lowermost mantle low velocity zones and seismic anisotropy have been detected within D''. In all cases there are significant questions regarding the mechanisms that generated and maintain these structures and provide further insight into the interaction between the core and mantle. In addition, laboratory experiments and computational studies, carried out under simulated Earth mantle conditions, impacted our understanding of the physical and chemical behaviour of deep mantle phases at relevant P-T conditions and their relation to the seismological observables. Core models must also account for the data provided by satellite missions on the details of rapid variations in the Earth’s magnetic field; and new historical, archeo- and paleo-magnetic reconstructions contribute greater understanding of the long term structure and behaviour of the Earth’s magnetic field. Our improving capabilities to monitor the deep Earth with seismic waves, derive physical and chemical properties of potential mantle phases using both experimental and computational approaches, and model geodynamic processes, promise to further enhance our understanding of this important part of our planet. The overwhelming complexity of the deep Earth, however, demands for a multidisciplinary approach in order to proceed towards an integrated picture, which best satisfies the constraints that emerge from the various
disciplines.

This session aims at contributions from mineral physics (both experimental and computational), geochemistry, seismology, and geodynamics, which enhance our knowledge about the composition, structure, dynamics, and evolution of the deep Earth.