Mantle viscosity beneath the Hudson Bay: an inversion based on the Metropolis algorithm
[1] We revisit the problem of inferring mantle viscosity from postglacial relative sea level (RSL) data across the Hudson Bay. We invert a recently revised data set using the Metropolis algorithm together with an annealing schedule: this method, which is well established in geophysics, is applied he...
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Online Access: | http://hdl.handle.net/11576/1886067 https://doi.org/10.1029/2001JB000585 http://onlinelibrary.wiley.com/doi/10.1029/2001JB000585/full |
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ftunivurbino:oai:ora.uniurb.it:11576/1886067 2024-04-14T08:12:49+00:00 Mantle viscosity beneath the Hudson Bay: an inversion based on the Metropolis algorithm CIANETTI S. GIUNCHI C. SPADA, GIORGIO Cianetti, S. Giunchi, C. Spada, Giorgio 2002 STAMPA http://hdl.handle.net/11576/1886067 https://doi.org/10.1029/2001JB000585 http://onlinelibrary.wiley.com/doi/10.1029/2001JB000585/full eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000181224400001 volume:107 issue:B12 firstpage:2352 numberofpages:14 journal:JOURNAL OF GEOPHYSICAL RESEARCH http://hdl.handle.net/11576/1886067 doi:10.1029/2001JB000585 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-0038741977 http://onlinelibrary.wiley.com/doi/10.1029/2001JB000585/full INDEX TERMS: 1213 Geodesy and Gravity: Earth’s interior—dynamics (8115 8120) 8120 Tectonophysics: Dynamics of lithosphere and mantle—general 8162 Tectonophysics: Evolution of the Earth: Rheology—mantle KEYWORDS: Postglacial rebound mantle viscosity simulated annealing info:eu-repo/semantics/article 2002 ftunivurbino https://doi.org/10.1029/2001JB000585 2024-03-21T17:06:40Z [1] We revisit the problem of inferring mantle viscosity from postglacial relative sea level (RSL) data across the Hudson Bay. We invert a recently revised data set using the Metropolis algorithm together with an annealing schedule: this method, which is well established in geophysics, is applied here for the first time to the glacial isostatic adjustment problem. The Metropolis algorithm performs a search, which is not limited to downhill moves in the model space and thus is less influenced by local minima of the misfit than traditional inverse approaches. Furthermore, its CPU requirements are far superior to Monte Carlo methods. The major drawbacks include slow convergence and the need for careful tuning of crucial variables such as the temperature schedule and the increment in the model space. When all the Hudson Bay RSL data are considered, and the viscosity of the upper mantle above the 670 km discontinuity is inverted, the best fitting solution is characterized by a viscosity close to 2 1020 Pa s. However, when the shallow upper mantle and transition zone viscosity are separately inverted, other less traditional solutions with a more complex viscosity structure are found to be equally possible. A stable feature is the lower mantle viscosity, which is generally found to be close to the value of 1021 Pa s in all of the stochastic inversions we have performed. The solutions agree with previous findings concerning both postglacial rebound observables and global geodynamics signatures. Article in Journal/Newspaper Hudson Bay Università degli Studi di Urbino: CINECA IRIS Hudson Bay Hudson Journal of Geophysical Research: Solid Earth 107 B12 ETG 12-1 ETG 12-15 |
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Università degli Studi di Urbino: CINECA IRIS |
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ftunivurbino |
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English |
topic |
INDEX TERMS: 1213 Geodesy and Gravity: Earth’s interior—dynamics (8115 8120) 8120 Tectonophysics: Dynamics of lithosphere and mantle—general 8162 Tectonophysics: Evolution of the Earth: Rheology—mantle KEYWORDS: Postglacial rebound mantle viscosity simulated annealing |
spellingShingle |
INDEX TERMS: 1213 Geodesy and Gravity: Earth’s interior—dynamics (8115 8120) 8120 Tectonophysics: Dynamics of lithosphere and mantle—general 8162 Tectonophysics: Evolution of the Earth: Rheology—mantle KEYWORDS: Postglacial rebound mantle viscosity simulated annealing CIANETTI S. GIUNCHI C. SPADA, GIORGIO Mantle viscosity beneath the Hudson Bay: an inversion based on the Metropolis algorithm |
topic_facet |
INDEX TERMS: 1213 Geodesy and Gravity: Earth’s interior—dynamics (8115 8120) 8120 Tectonophysics: Dynamics of lithosphere and mantle—general 8162 Tectonophysics: Evolution of the Earth: Rheology—mantle KEYWORDS: Postglacial rebound mantle viscosity simulated annealing |
description |
[1] We revisit the problem of inferring mantle viscosity from postglacial relative sea level (RSL) data across the Hudson Bay. We invert a recently revised data set using the Metropolis algorithm together with an annealing schedule: this method, which is well established in geophysics, is applied here for the first time to the glacial isostatic adjustment problem. The Metropolis algorithm performs a search, which is not limited to downhill moves in the model space and thus is less influenced by local minima of the misfit than traditional inverse approaches. Furthermore, its CPU requirements are far superior to Monte Carlo methods. The major drawbacks include slow convergence and the need for careful tuning of crucial variables such as the temperature schedule and the increment in the model space. When all the Hudson Bay RSL data are considered, and the viscosity of the upper mantle above the 670 km discontinuity is inverted, the best fitting solution is characterized by a viscosity close to 2 1020 Pa s. However, when the shallow upper mantle and transition zone viscosity are separately inverted, other less traditional solutions with a more complex viscosity structure are found to be equally possible. A stable feature is the lower mantle viscosity, which is generally found to be close to the value of 1021 Pa s in all of the stochastic inversions we have performed. The solutions agree with previous findings concerning both postglacial rebound observables and global geodynamics signatures. |
author2 |
Cianetti, S. Giunchi, C. Spada, Giorgio |
format |
Article in Journal/Newspaper |
author |
CIANETTI S. GIUNCHI C. SPADA, GIORGIO |
author_facet |
CIANETTI S. GIUNCHI C. SPADA, GIORGIO |
author_sort |
CIANETTI S. |
title |
Mantle viscosity beneath the Hudson Bay: an inversion based on the Metropolis algorithm |
title_short |
Mantle viscosity beneath the Hudson Bay: an inversion based on the Metropolis algorithm |
title_full |
Mantle viscosity beneath the Hudson Bay: an inversion based on the Metropolis algorithm |
title_fullStr |
Mantle viscosity beneath the Hudson Bay: an inversion based on the Metropolis algorithm |
title_full_unstemmed |
Mantle viscosity beneath the Hudson Bay: an inversion based on the Metropolis algorithm |
title_sort |
mantle viscosity beneath the hudson bay: an inversion based on the metropolis algorithm |
publishDate |
2002 |
url |
http://hdl.handle.net/11576/1886067 https://doi.org/10.1029/2001JB000585 http://onlinelibrary.wiley.com/doi/10.1029/2001JB000585/full |
geographic |
Hudson Bay Hudson |
geographic_facet |
Hudson Bay Hudson |
genre |
Hudson Bay |
genre_facet |
Hudson Bay |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000181224400001 volume:107 issue:B12 firstpage:2352 numberofpages:14 journal:JOURNAL OF GEOPHYSICAL RESEARCH http://hdl.handle.net/11576/1886067 doi:10.1029/2001JB000585 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-0038741977 http://onlinelibrary.wiley.com/doi/10.1029/2001JB000585/full |
op_doi |
https://doi.org/10.1029/2001JB000585 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
107 |
container_issue |
B12 |
container_start_page |
ETG 12-1 |
op_container_end_page |
ETG 12-15 |
_version_ |
1796310670804779008 |