Lateral viscosity variations and post-glacial rebound: effects on present-day VLBI baseline deformations
By means of a finite element algorithm we investigate the effects of lateral viscosity variations upon the horizontal motions currently detected by VLBI techniques in Europe. Our axisymmetric flat models, appropriate to describe the rebound due to the melting of the Fennoscandia ice‐sheet, are chara...
Published in: | Geophysical Research Letters |
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Online Access: | http://hdl.handle.net/11576/1886065 https://doi.org/10.1029/96GL03773 http://onlinelibrary.wiley.com/doi/10.1029/96GL03773/full |
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ftunivurbino:oai:ora.uniurb.it:11576/1886065 2024-04-14T08:11:26+00:00 Lateral viscosity variations and post-glacial rebound: effects on present-day VLBI baseline deformations C. GIUNCHI R. SABADINI SPADA, GIORGIO C., Giunchi Spada, Giorgio R., Sabadini 1997 STAMPA http://hdl.handle.net/11576/1886065 https://doi.org/10.1029/96GL03773 http://onlinelibrary.wiley.com/doi/10.1029/96GL03773/full eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:A1997WB78600004 volume:24 issue:1 firstpage:13 lastpage:16 numberofpages:4 journal:GEOPHYSICAL RESEARCH LETTERS http://hdl.handle.net/11576/1886065 doi:10.1029/96GL03773 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-0030804727 http://onlinelibrary.wiley.com/doi/10.1029/96GL03773/full Engineering controlled terms: Algorithm Deformation Glacial geology Glacier Finite element method Ice Melting Viscosity Continental collision Finite element algorithm Horizontal deformation Horizontal motion Post glacial rebound Simple geometrie Viscosity increase Viscosity variations Engineering main heading: Viscosity Glaciers Engineering uncontrolled terms: Baseline deformation Lateral viscosity variation Post-glacial rebound GEOBASE Subject Index: mantle rheology VLBI Regional Index: Europe info:eu-repo/semantics/article 1997 ftunivurbino https://doi.org/10.1029/96GL03773 2024-03-21T17:01:51Z By means of a finite element algorithm we investigate the effects of lateral viscosity variations upon the horizontal motions currently detected by VLBI techniques in Europe. Our axisymmetric flat models, appropriate to describe the rebound due to the melting of the Fennoscandia ice‐sheet, are characterized by a layered compressible mantle with linear Maxwell rheology. We have first computed the time‐evolution of theoretical baselines characterized by a simple geometry. In agreement with previous results, the rates of horizontal deformation have been found to be greatly sensitive to both lateral viscosity variations and deep mantle stratification, especially for baselines located in the vicinity of the ice sheet margin. To complete our study, we have compared our numerical results with the observed time‐evolutions of relevant European baselines. Onsala‐Wettzell and Onsala‐Eflsberg are fitted by a laterally varying asthenosphere and sharp viscosity increase in the lower mantle; longer baselines, connecting these sites to Medicina (northern Italy), indicate that post glacial rebound is responsible only for a fraction of the VLBI observations, the residual being thus attributable to continental collision in the Mediterranean Sea. Article in Journal/Newspaper Fennoscandia Ice Sheet Università degli Studi di Urbino: CINECA IRIS Geophysical Research Letters 24 1 13 16 |
institution |
Open Polar |
collection |
Università degli Studi di Urbino: CINECA IRIS |
op_collection_id |
ftunivurbino |
language |
English |
topic |
Engineering controlled terms: Algorithm Deformation Glacial geology Glacier Finite element method Ice Melting Viscosity Continental collision Finite element algorithm Horizontal deformation Horizontal motion Post glacial rebound Simple geometrie Viscosity increase Viscosity variations Engineering main heading: Viscosity Glaciers Engineering uncontrolled terms: Baseline deformation Lateral viscosity variation Post-glacial rebound GEOBASE Subject Index: mantle rheology VLBI Regional Index: Europe |
spellingShingle |
Engineering controlled terms: Algorithm Deformation Glacial geology Glacier Finite element method Ice Melting Viscosity Continental collision Finite element algorithm Horizontal deformation Horizontal motion Post glacial rebound Simple geometrie Viscosity increase Viscosity variations Engineering main heading: Viscosity Glaciers Engineering uncontrolled terms: Baseline deformation Lateral viscosity variation Post-glacial rebound GEOBASE Subject Index: mantle rheology VLBI Regional Index: Europe C. GIUNCHI R. SABADINI SPADA, GIORGIO Lateral viscosity variations and post-glacial rebound: effects on present-day VLBI baseline deformations |
topic_facet |
Engineering controlled terms: Algorithm Deformation Glacial geology Glacier Finite element method Ice Melting Viscosity Continental collision Finite element algorithm Horizontal deformation Horizontal motion Post glacial rebound Simple geometrie Viscosity increase Viscosity variations Engineering main heading: Viscosity Glaciers Engineering uncontrolled terms: Baseline deformation Lateral viscosity variation Post-glacial rebound GEOBASE Subject Index: mantle rheology VLBI Regional Index: Europe |
description |
By means of a finite element algorithm we investigate the effects of lateral viscosity variations upon the horizontal motions currently detected by VLBI techniques in Europe. Our axisymmetric flat models, appropriate to describe the rebound due to the melting of the Fennoscandia ice‐sheet, are characterized by a layered compressible mantle with linear Maxwell rheology. We have first computed the time‐evolution of theoretical baselines characterized by a simple geometry. In agreement with previous results, the rates of horizontal deformation have been found to be greatly sensitive to both lateral viscosity variations and deep mantle stratification, especially for baselines located in the vicinity of the ice sheet margin. To complete our study, we have compared our numerical results with the observed time‐evolutions of relevant European baselines. Onsala‐Wettzell and Onsala‐Eflsberg are fitted by a laterally varying asthenosphere and sharp viscosity increase in the lower mantle; longer baselines, connecting these sites to Medicina (northern Italy), indicate that post glacial rebound is responsible only for a fraction of the VLBI observations, the residual being thus attributable to continental collision in the Mediterranean Sea. |
author2 |
C., Giunchi Spada, Giorgio R., Sabadini |
format |
Article in Journal/Newspaper |
author |
C. GIUNCHI R. SABADINI SPADA, GIORGIO |
author_facet |
C. GIUNCHI R. SABADINI SPADA, GIORGIO |
author_sort |
C. GIUNCHI |
title |
Lateral viscosity variations and post-glacial rebound: effects on present-day VLBI baseline deformations |
title_short |
Lateral viscosity variations and post-glacial rebound: effects on present-day VLBI baseline deformations |
title_full |
Lateral viscosity variations and post-glacial rebound: effects on present-day VLBI baseline deformations |
title_fullStr |
Lateral viscosity variations and post-glacial rebound: effects on present-day VLBI baseline deformations |
title_full_unstemmed |
Lateral viscosity variations and post-glacial rebound: effects on present-day VLBI baseline deformations |
title_sort |
lateral viscosity variations and post-glacial rebound: effects on present-day vlbi baseline deformations |
publishDate |
1997 |
url |
http://hdl.handle.net/11576/1886065 https://doi.org/10.1029/96GL03773 http://onlinelibrary.wiley.com/doi/10.1029/96GL03773/full |
genre |
Fennoscandia Ice Sheet |
genre_facet |
Fennoscandia Ice Sheet |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:A1997WB78600004 volume:24 issue:1 firstpage:13 lastpage:16 numberofpages:4 journal:GEOPHYSICAL RESEARCH LETTERS http://hdl.handle.net/11576/1886065 doi:10.1029/96GL03773 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-0030804727 http://onlinelibrary.wiley.com/doi/10.1029/96GL03773/full |
op_doi |
https://doi.org/10.1029/96GL03773 |
container_title |
Geophysical Research Letters |
container_volume |
24 |
container_issue |
1 |
container_start_page |
13 |
op_container_end_page |
16 |
_version_ |
1796309147051884544 |