Authors:	Reuber, Georg S. Simons, Frederik J.
Title:	Multi-physics adjoint modeling of Earth structure : combining gravimetric, seismic, and geodynamic inversions
Online publication date:	7-May-2021
Year of first publication:	2020
Language:	english
Abstract:	We discuss the resolving power of three geophysical imaging and inversion techniques, and their combination, for the reconstruction of material parameters in the Earth’s subsurface. The governing equations are those of Newton and Poisson for gravitational problems, the acoustic wave equation under Hookean elasticity for seismology, and the geodynamics equations of Stokes for incompressible steady-state flow in the mantle. The observables are the gravitational potential, the seismic displacement, and the surface velocity, all measured at the surface. The inversion parameters of interest are the mass density, the acoustic wave speed, and the viscosity. These systems of partial differential equations and their adjoints were implemented in a single Python code using the finite-element library FeNICS. To investigate the shape of the cost functions, we present a grid search in the parameter space for three end-member geological settings: a falling block, a subduction zone, and a mantle plume. The performance of a gradient-based inversion for each single observable separately, and in combination, is presented. We furthermore investigate the performance of a shape-optimizing inverse method, when the material is known, and an inversion that inverts for the material parameters of an anomaly with known shape.
DDC:	550 Geowissenschaften 550 Earth sciences
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 09 Chemie, Pharmazie u. Geowissensch.
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-5780
Version:	Published version
Publication type:	Zeitschriftenaufsatz
License:	CC BY
Information on rights of use:	https://creativecommons.org/licenses/by/4.0/
Journal:	GEM : international journal on geomathematics 11
Pages or article number:	30
Publisher:	Springer
Publisher place:	Berlin u.a.
Issue date:	2020
ISSN:	1869-2680
Publisher URL:	https://doi.org/10.1007/s13137-020-00166-8
Publisher DOI:	10.1007/s13137-020-00166-8
Appears in collections:	JGU-Publikationen