Print Email Facebook Twitter Estimating geodynamic model parameters from geodetic observations using a particle method Title Estimating geodynamic model parameters from geodetic observations using a particle method Author Marsman, C. P. (Universiteit Utrecht) Vossepoel, F.C. (TU Delft Reservoir Engineering) Van Dinther, Y. (Universiteit Utrecht) Govers, R. (Universiteit Utrecht) Date 2024 Abstract Bayesian-based data assimilation methods integrate observational data into geophysical forward models to obtain the temporal evolution of an improved state vector, including its uncertainties. We explore the potential of a variant, a particle method, to estimate mechanical parameters of the overriding plate during the interseismic period. Here we assimilate vertical surface displacements into an elementary flexural model to estimate the elastic thickness of the overriding plate, and the locations and magnitudes of line loads acting on the overriding plate to produce flexure. Assimilation of synthetic observations sampled from a different forward model than is used in the particle method, reveal that synthetic seafloor data within 150 km from the trench are required to properly constrain parameters for long wavelength solutions of the upper plate (i.e. wavelength ∼500 km). Assimilation of synthetic observations sampled from the same flexural model used in the particle method shows remarkable convergence towards the true parameters with synthetic on-land data only for short to intermediate wavelength solutions (i.e. wavelengths between ∼100 and 300 km). In real-data assimilation experiments we assign representation errors due to discrepancies between our incorrect or incomplete physical model and the data. When assimilating continental data prior to the 2011 Mw Tohoku-Oki earthquake (1997-2000), an unrealistically low effective elastic plate thickness for Tohoku of ∼5-7 km is estimated. Our synthetic experiments suggest that improvements to the physical forward model, such as the inclusion of a slab, a megathrust interface and viscoelasticity of the mantle, including accurate seafloor data, and additional geodetic observations, may refine our estimates of the effective elastic plate thickness. Overall, we demonstrate the potential of using the particle method to constrain geodynamic parameters by providing constraints on parameters and corresponding uncertainty values. Using the particle method, we provide insights into the data network sensitivity and identify parameter trade-offs. Subject Inverse theoryLithospheric flexureProbabilistic forecastingStatistical methodsSubduction zone processesTime-series analysis To reference this document use: http://resolver.tudelft.nl/uuid:35c1966b-74d4-40c2-b43d-05daf70246b5 DOI https://doi.org/10.1093/gji/ggad450 ISSN 0956-540X Source Geophysical Journal International, 236 (3), 1183-1205 Part of collection Institutional Repository Document type journal article Rights © 2024 C. P. Marsman, F.C. Vossepoel, Y. Van Dinther, R. Govers Files PDF ggad450.pdf 3.27 MB Close viewer /islandora/object/uuid:35c1966b-74d4-40c2-b43d-05daf70246b5/datastream/OBJ/view