AxiSEM3D: a new fast method for global wave propagation in 3-D Earth models with undulating discontinuities

Kuangdai Leng, University of Oxford, Oxford, United Kingdom, Tarje Nissen-Meyer, University of Oxford, Department of Earth Sciences, Oxford, United Kingdom, Martin van Driel, ETH Zurich, Institute of Geophysics, Zurich, Switzerland and David Al-Attar, University of Cambridge, Department of Earth Sciences, Cambridge, United Kingdom