Crustal structure of the Transantarctic Mountains, Ellsworth Mountains and Marie Byrd Land, Antarctica: constraints on shear wave velocities, Poisson's ratios and Moho depths
A uniform set of crustal parameters for seismic stations deployed on rock in West Antarctica and the Transantarctic Mountains (TAM) has been obtained to help elucidate similarities and differences in crustal structure within and between several tectonic blocks that make up these regions. P-wave rece...
Published in: | Geophysical Journal International |
---|---|
Main Authors: | , , , , , , , , , |
Format: | Text |
Language: | unknown |
Published: |
ScholarWorks@CWU
2017
|
Subjects: | |
Online Access: | https://digitalcommons.cwu.edu/geological_sciences/112 https://doi.org/10.1093/gji/ggx333 |
id |
ftcwashingtonuni:oai:digitalcommons.cwu.edu:geological_sciences-1112 |
---|---|
record_format |
openpolar |
spelling |
ftcwashingtonuni:oai:digitalcommons.cwu.edu:geological_sciences-1112 2023-05-15T13:47:32+02:00 Crustal structure of the Transantarctic Mountains, Ellsworth Mountains and Marie Byrd Land, Antarctica: constraints on shear wave velocities, Poisson's ratios and Moho depths Ramirez, C. Nyblade, Andrew Emry, E. L. Julià, J. Sun, X. Anandakrishnan, Sridhar Wiens, D. A. Huerta, Audrey D. Winberry, J. Paul Wilson, T. 2017-08-04T07:00:00Z https://digitalcommons.cwu.edu/geological_sciences/112 https://doi.org/10.1093/gji/ggx333 unknown ScholarWorks@CWU https://digitalcommons.cwu.edu/geological_sciences/112 http://ezp.lib.cwu.edu/login?url=http://dx.doi.org/10.1093/gji/ggx333 © The Authors 2017. Geological Sciences Faculty Scholarship Structure of the Earth Antarctica Crustal structure Geophysics and Seismology Tectonics and Structure text 2017 ftcwashingtonuni https://doi.org/10.1093/gji/ggx333 2022-10-20T20:30:12Z A uniform set of crustal parameters for seismic stations deployed on rock in West Antarctica and the Transantarctic Mountains (TAM) has been obtained to help elucidate similarities and differences in crustal structure within and between several tectonic blocks that make up these regions. P-wave receiver functions have been analysed using the H–κ stacking method to develop estimates of thickness and bulk Poisson's ratio for the crust, and jointly inverted with surface wave dispersion measurements to obtain depth-dependent shear wave velocity models for the crust and uppermost mantle. The results from 33 stations are reported, including three stations for which no previous results were available. The average crustal thickness is 30 ± 5 km along the TAM front, and 38 ± 2 km in the interior of the mountain range. The average Poisson's ratios for these two regions are 0.25 ± 0.03 and 0.26 ± 0.02, respectively, and they have similar average crustal Vs of 3.7 ± 0.1 km s−1. At multiple stations within the TAM, we observe evidence for mafic layering within or at the base of the crust, which may have resulted from the Ferrar magmatic event. The Ellsworth Mountains have an average crustal thickness of 37 ± 2 km, a Poisson's ratio of 0.27, and average crustal Vs of 3.7 ± 0.1 km s−1, similar to the TAM. This similarity is consistent with interpretations of the Ellsworth Mountains as a tectonically rotated TAM block. The Ross Island region has an average Moho depth of 25 ± 1 km, an average crustal Vs of 3.6 ± 0.1 km s−1 and Poisson's ratio of 0.30, consistent with the mafic Cenozoic volcanism found there and its proximity to the Terror Rift. Marie Byrd Land has an average crustal thickness of 30 ± 2 km, Poisson's ratio of 0.25 ± 0.04 and crustal Vs of 3.7 ± 0.1 km s−1. One station (SILY) in Marie Byrd Land is near an area of recent volcanism and deep (25–40 km) seismicity, and has a high Poisson's ratio, consistent with the presence of partial melt in the crust. Text Antarc* Antarctica Marie Byrd Land Ross Island West Antarctica Central Washington University: ScholarWorks Byrd Ellsworth Mountains ENVELOPE(-85.000,-85.000,-78.750,-78.750) Marie Byrd Land ENVELOPE(-130.000,-130.000,-78.000,-78.000) Ross Island Transantarctic Mountains West Antarctica Geophysical Journal International 211 3 1328 1340 |
institution |
Open Polar |
collection |
Central Washington University: ScholarWorks |
op_collection_id |
ftcwashingtonuni |
language |
unknown |
topic |
Structure of the Earth Antarctica Crustal structure Geophysics and Seismology Tectonics and Structure |
spellingShingle |
Structure of the Earth Antarctica Crustal structure Geophysics and Seismology Tectonics and Structure Ramirez, C. Nyblade, Andrew Emry, E. L. Julià, J. Sun, X. Anandakrishnan, Sridhar Wiens, D. A. Huerta, Audrey D. Winberry, J. Paul Wilson, T. Crustal structure of the Transantarctic Mountains, Ellsworth Mountains and Marie Byrd Land, Antarctica: constraints on shear wave velocities, Poisson's ratios and Moho depths |
topic_facet |
Structure of the Earth Antarctica Crustal structure Geophysics and Seismology Tectonics and Structure |
description |
A uniform set of crustal parameters for seismic stations deployed on rock in West Antarctica and the Transantarctic Mountains (TAM) has been obtained to help elucidate similarities and differences in crustal structure within and between several tectonic blocks that make up these regions. P-wave receiver functions have been analysed using the H–κ stacking method to develop estimates of thickness and bulk Poisson's ratio for the crust, and jointly inverted with surface wave dispersion measurements to obtain depth-dependent shear wave velocity models for the crust and uppermost mantle. The results from 33 stations are reported, including three stations for which no previous results were available. The average crustal thickness is 30 ± 5 km along the TAM front, and 38 ± 2 km in the interior of the mountain range. The average Poisson's ratios for these two regions are 0.25 ± 0.03 and 0.26 ± 0.02, respectively, and they have similar average crustal Vs of 3.7 ± 0.1 km s−1. At multiple stations within the TAM, we observe evidence for mafic layering within or at the base of the crust, which may have resulted from the Ferrar magmatic event. The Ellsworth Mountains have an average crustal thickness of 37 ± 2 km, a Poisson's ratio of 0.27, and average crustal Vs of 3.7 ± 0.1 km s−1, similar to the TAM. This similarity is consistent with interpretations of the Ellsworth Mountains as a tectonically rotated TAM block. The Ross Island region has an average Moho depth of 25 ± 1 km, an average crustal Vs of 3.6 ± 0.1 km s−1 and Poisson's ratio of 0.30, consistent with the mafic Cenozoic volcanism found there and its proximity to the Terror Rift. Marie Byrd Land has an average crustal thickness of 30 ± 2 km, Poisson's ratio of 0.25 ± 0.04 and crustal Vs of 3.7 ± 0.1 km s−1. One station (SILY) in Marie Byrd Land is near an area of recent volcanism and deep (25–40 km) seismicity, and has a high Poisson's ratio, consistent with the presence of partial melt in the crust. |
format |
Text |
author |
Ramirez, C. Nyblade, Andrew Emry, E. L. Julià, J. Sun, X. Anandakrishnan, Sridhar Wiens, D. A. Huerta, Audrey D. Winberry, J. Paul Wilson, T. |
author_facet |
Ramirez, C. Nyblade, Andrew Emry, E. L. Julià, J. Sun, X. Anandakrishnan, Sridhar Wiens, D. A. Huerta, Audrey D. Winberry, J. Paul Wilson, T. |
author_sort |
Ramirez, C. |
title |
Crustal structure of the Transantarctic Mountains, Ellsworth Mountains and Marie Byrd Land, Antarctica: constraints on shear wave velocities, Poisson's ratios and Moho depths |
title_short |
Crustal structure of the Transantarctic Mountains, Ellsworth Mountains and Marie Byrd Land, Antarctica: constraints on shear wave velocities, Poisson's ratios and Moho depths |
title_full |
Crustal structure of the Transantarctic Mountains, Ellsworth Mountains and Marie Byrd Land, Antarctica: constraints on shear wave velocities, Poisson's ratios and Moho depths |
title_fullStr |
Crustal structure of the Transantarctic Mountains, Ellsworth Mountains and Marie Byrd Land, Antarctica: constraints on shear wave velocities, Poisson's ratios and Moho depths |
title_full_unstemmed |
Crustal structure of the Transantarctic Mountains, Ellsworth Mountains and Marie Byrd Land, Antarctica: constraints on shear wave velocities, Poisson's ratios and Moho depths |
title_sort |
crustal structure of the transantarctic mountains, ellsworth mountains and marie byrd land, antarctica: constraints on shear wave velocities, poisson's ratios and moho depths |
publisher |
ScholarWorks@CWU |
publishDate |
2017 |
url |
https://digitalcommons.cwu.edu/geological_sciences/112 https://doi.org/10.1093/gji/ggx333 |
long_lat |
ENVELOPE(-85.000,-85.000,-78.750,-78.750) ENVELOPE(-130.000,-130.000,-78.000,-78.000) |
geographic |
Byrd Ellsworth Mountains Marie Byrd Land Ross Island Transantarctic Mountains West Antarctica |
geographic_facet |
Byrd Ellsworth Mountains Marie Byrd Land Ross Island Transantarctic Mountains West Antarctica |
genre |
Antarc* Antarctica Marie Byrd Land Ross Island West Antarctica |
genre_facet |
Antarc* Antarctica Marie Byrd Land Ross Island West Antarctica |
op_source |
Geological Sciences Faculty Scholarship |
op_relation |
https://digitalcommons.cwu.edu/geological_sciences/112 http://ezp.lib.cwu.edu/login?url=http://dx.doi.org/10.1093/gji/ggx333 |
op_rights |
© The Authors 2017. |
op_doi |
https://doi.org/10.1093/gji/ggx333 |
container_title |
Geophysical Journal International |
container_volume |
211 |
container_issue |
3 |
container_start_page |
1328 |
op_container_end_page |
1340 |
_version_ |
1766247274729439232 |