0000000000319728

AUTHOR

Lukas Holbach

showing 2 related works from this author

Inferring rheology and geometry of subsurface structures by adjoint-based inversion of principal stress directions

2020

SUMMARY Imaging subsurface structures, such as salt domes, magma reservoirs or subducting plates, is a major challenge in geophysics. Seismic imaging methods are, so far, the most precise methods to open a window into the Earth. However, the methods may not yield the exact depth or size of the imaged feature and may become distorted by phenomena such as seismic anisotropy, fluid flow, or compositional variations. A useful complementary method is therefore to simulate the mechanical behaviour of rocks on large timescales, and compare model predictions with observations. Recent studies have used the (non-linear) Stokes equations and geometries from seismic studies in combination with an adjoi…

Seismic anisotropy010504 meteorology & atmospheric sciencesDiscretizationGeophysical imagingObservableGeometry010502 geochemistry & geophysics01 natural sciencesPhysics::GeophysicsNonlinear systemGeophysicsRheologyGeochemistry and Petrology13. Climate actionFluid dynamicsGeology0105 earth and related environmental sciencesSalt domeGeophysical Journal International
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Adjoint-based inversion for porosity in shallow reservoirs using pseudo-transient solvers for non-linear hydro-mechanical processes

2020

Abstract Porous flow is of major importance in the shallow subsurface, since it directly impacts on reservoir-scale processes such as waste fluid sequestration or oil and gas exploration. Coupled and non-linear hydro-mechanical processes describe the motion of a low-viscous fluid interacting with a higher viscous porous rock matrix. This two-phase flow may trigger the initiation of solitary waves of porosity, further developing into vertical high-porosity pipes or chimneys. These preferred fluid escape features may lead to localised and fast vertical flow pathways potentially problematic in the case of for instance CO2 sequestration. Constraining the porosity and the non-linearly related pe…

PointwiseNumerical AnalysisPhysics and Astronomy (miscellaneous)Geophysical imagingApplied MathematicsFinite difference method010103 numerical & computational mathematicsMechanics01 natural sciencesPhysics::GeophysicsComputer Science ApplicationsPhysics::Fluid Dynamics010101 applied mathematicsComputational MathematicsNonlinear systemPermeability (earth sciences)Modeling and SimulationTwo-phase flow0101 mathematicsPorosityGradient descentGeologyJournal of Computational Physics
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