Seismic structure of Iceland from Rayleigh wave inversions and geodynamic implications
Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Earth and Planetary Science Letters 241 (2006): 901-912, doi:10.1016/j.epsl.2005.10.0...
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ftwhoas:oai:darchive.mblwhoilibrary.org:1912/649 2023-05-15T16:42:22+02:00 Seismic structure of Iceland from Rayleigh wave inversions and geodynamic implications Li, Aibing Detrick, Robert S. 2005-10-25 413247 bytes application/pdf https://hdl.handle.net/1912/649 en_US eng https://doi.org/10.1016/j.epsl.2005.10.031 https://hdl.handle.net/1912/649 Rayleigh wave Iceland Crust Upper mantle Hotspot Preprint 2005 ftwhoas https://doi.org/10.1016/j.epsl.2005.10.031 2022-05-28T22:56:57Z Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Earth and Planetary Science Letters 241 (2006): 901-912, doi:10.1016/j.epsl.2005.10.031. We have constrained the shear-wave structure of crust and upper mantle beneath Iceland by analyzing fundamental mode Rayleigh waves recorded at the ICEMELT and HOTSPOT seismic stations in Iceland. The crust varies in thickness from 20 to 28 km in western and northern Iceland and from 26 to 34 km in eastern Iceland. The thickest crust of 34-40 km lies in central Iceland, roughly 100 km west to the current location of the Iceland hotspot. The crust at the hotspot is ~32 km thick and is underlain by low shearwave velocities of 4.0-4.1 km/s in the uppermost mantle, indicating that the Moho at the hotspot is probably a weak discontinuity. This low velocity anomaly beneath the hotspot could be associated with partial melting and hot temperature. The lithosphere in Iceland is confined above 60 km and a low velocity zone (LVZ) is imaged at depths of 60 to 120 km. Shear wave velocity in the LVZ is up to 10% lower than a global reference model, indicating the influence of the Mid-Atlantic Ridge and the hotspot in Iceland. The lowest velocities in the LVZ are found beneath the rift zones, suggesting that plume material is channeled along the Mid-Atlantic Ridge. At depths of 100 to 200 km, low velocity anomalies appear at the Tjornes fracture zone to the north of Iceland and beneath the western volcanic zone in southwestern Iceland. Interestingly, a relatively fast anomaly is imaged beneath the hotspot with its center at ~135 km depth, which could be due to radial anisotropy associated with the strong upwelling within the plume stem or an Mgenriched mantle residual caused by the extensive extraction of melts. This work is supported by University of Houston, Woods Hole Oceanographic Institution, and NSF grant OCE-0117938. Report Iceland Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) Mid-Atlantic Ridge Earth and Planetary Science Letters 241 3-4 901 912 |
institution |
Open Polar |
collection |
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) |
op_collection_id |
ftwhoas |
language |
English |
topic |
Rayleigh wave Iceland Crust Upper mantle Hotspot |
spellingShingle |
Rayleigh wave Iceland Crust Upper mantle Hotspot Li, Aibing Detrick, Robert S. Seismic structure of Iceland from Rayleigh wave inversions and geodynamic implications |
topic_facet |
Rayleigh wave Iceland Crust Upper mantle Hotspot |
description |
Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Earth and Planetary Science Letters 241 (2006): 901-912, doi:10.1016/j.epsl.2005.10.031. We have constrained the shear-wave structure of crust and upper mantle beneath Iceland by analyzing fundamental mode Rayleigh waves recorded at the ICEMELT and HOTSPOT seismic stations in Iceland. The crust varies in thickness from 20 to 28 km in western and northern Iceland and from 26 to 34 km in eastern Iceland. The thickest crust of 34-40 km lies in central Iceland, roughly 100 km west to the current location of the Iceland hotspot. The crust at the hotspot is ~32 km thick and is underlain by low shearwave velocities of 4.0-4.1 km/s in the uppermost mantle, indicating that the Moho at the hotspot is probably a weak discontinuity. This low velocity anomaly beneath the hotspot could be associated with partial melting and hot temperature. The lithosphere in Iceland is confined above 60 km and a low velocity zone (LVZ) is imaged at depths of 60 to 120 km. Shear wave velocity in the LVZ is up to 10% lower than a global reference model, indicating the influence of the Mid-Atlantic Ridge and the hotspot in Iceland. The lowest velocities in the LVZ are found beneath the rift zones, suggesting that plume material is channeled along the Mid-Atlantic Ridge. At depths of 100 to 200 km, low velocity anomalies appear at the Tjornes fracture zone to the north of Iceland and beneath the western volcanic zone in southwestern Iceland. Interestingly, a relatively fast anomaly is imaged beneath the hotspot with its center at ~135 km depth, which could be due to radial anisotropy associated with the strong upwelling within the plume stem or an Mgenriched mantle residual caused by the extensive extraction of melts. This work is supported by University of Houston, Woods Hole Oceanographic Institution, and NSF grant OCE-0117938. |
format |
Report |
author |
Li, Aibing Detrick, Robert S. |
author_facet |
Li, Aibing Detrick, Robert S. |
author_sort |
Li, Aibing |
title |
Seismic structure of Iceland from Rayleigh wave inversions and geodynamic implications |
title_short |
Seismic structure of Iceland from Rayleigh wave inversions and geodynamic implications |
title_full |
Seismic structure of Iceland from Rayleigh wave inversions and geodynamic implications |
title_fullStr |
Seismic structure of Iceland from Rayleigh wave inversions and geodynamic implications |
title_full_unstemmed |
Seismic structure of Iceland from Rayleigh wave inversions and geodynamic implications |
title_sort |
seismic structure of iceland from rayleigh wave inversions and geodynamic implications |
publishDate |
2005 |
url |
https://hdl.handle.net/1912/649 |
geographic |
Mid-Atlantic Ridge |
geographic_facet |
Mid-Atlantic Ridge |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
https://doi.org/10.1016/j.epsl.2005.10.031 https://hdl.handle.net/1912/649 |
op_doi |
https://doi.org/10.1016/j.epsl.2005.10.031 |
container_title |
Earth and Planetary Science Letters |
container_volume |
241 |
container_issue |
3-4 |
container_start_page |
901 |
op_container_end_page |
912 |
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1766032785552703488 |