Moho density contrast in Antarctica determined by satellite gravity and seismic models
As recovering the crust-mantle/Moho density contrast (MDC) significantly depends on the properties of the Earth’s crust and upper mantle, varying from place to place, it is an oversimplification to define a constant standard value for it. It is especially challenging in Antarctica, where almost all...
Published in: | Geophysical Journal International |
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Högskolan Väst, Avdelningen för Matematik, Data- och Lantmäteriteknik
2021
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Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-17514 https://doi.org/10.1093/gji/ggab069 |
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ftunivwest:oai:DiVA.org:hv-17514 2023-05-15T13:36:29+02:00 Moho density contrast in Antarctica determined by satellite gravity and seismic models Abrehdary, Majid Sjöberg, Lars 2021 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-17514 https://doi.org/10.1093/gji/ggab069 eng eng Högskolan Väst, Avdelningen för Matematik, Data- och Lantmäteriteknik Division of Geodesy and Satellite Positioning, Royal Institute of Technology (KTH), SE-10044 Stockholm, (SWE) Oxford University Press Geophysical Journal International, 0956-540X, 2021, 225:3, s. 1952-1962 orcid:0000-0001-7810-8829 http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-17514 doi:10.1093/gji/ggab069 Scopus 2-s2.0-85114994287 info:eu-repo/semantics/openAccess Structural geology Geological structures Geophysical applications Glacial Isostatic Adjustments Gravitational model Mid oceanic ridges Numerical results Satellite gravity Spatial resolution Seismology Geophysics Geofysik Article in journal info:eu-repo/semantics/article text 2021 ftunivwest https://doi.org/10.1093/gji/ggab069 2022-12-15T19:12:20Z As recovering the crust-mantle/Moho density contrast (MDC) significantly depends on the properties of the Earth’s crust and upper mantle, varying from place to place, it is an oversimplification to define a constant standard value for it. It is especially challenging in Antarctica, where almost all the bedrock is covered with a thick layer of ice, and seismic data cannot provide a sufficient spatial resolution for geological and geophysical applications. As an alternative, we determine the MDC in Antarctica and its surrounding seas with a resolution of 1°x 1° by the Vening Meinesz-Moritz gravimetric-isostatic technique using the XGM2019e Earth Gravitational Model and Earth2014 topographic/bathymetric information along with CRUST1.0 and CRUST19 seismic crustal models. The numerical results show that our model, named HVMDC20, varies from 81 kg m-3 in the Pacific Antarctic mid-oceanic ridge to 579 kg m-3 in the Gamburtsev Mountain Range in the central continent with a general average of 403 kg m-3. To assess our computations, we compare our estimates with those of some other gravimetric as well as seismic models (KTH11, GEMMA12C, KTH15C and CRUST1.0), illustrating that our estimates agree fairly well with KTH15C and CRUST1.0 but rather poor with the other models. In addition, we compare the geological signatures with HVMDC20, showing how the main geological structures contribute to the MDC. Finally, we study the remaining glacial isostatic adjustment effect on gravity to figure out how much it affects the MDC recovery, yielding a correlation of the optimum spectral window (7< n <12) between XGM2019e and W12a GIA models of the order of ~0.6 contributing within a negligible \pm 14 kg m-3 to the MDC. This study was supported by project no. 187/18 of the Swedish National Space Agency (SNSA) Article in Journal/Newspaper Antarc* Antarctic Antarctica University West, Trollhättan: Electronic Publications (DiVA) Antarctic Pacific Geophysical Journal International 225 3 1952 1962 |
institution |
Open Polar |
collection |
University West, Trollhättan: Electronic Publications (DiVA) |
op_collection_id |
ftunivwest |
language |
English |
topic |
Structural geology Geological structures Geophysical applications Glacial Isostatic Adjustments Gravitational model Mid oceanic ridges Numerical results Satellite gravity Spatial resolution Seismology Geophysics Geofysik |
spellingShingle |
Structural geology Geological structures Geophysical applications Glacial Isostatic Adjustments Gravitational model Mid oceanic ridges Numerical results Satellite gravity Spatial resolution Seismology Geophysics Geofysik Abrehdary, Majid Sjöberg, Lars Moho density contrast in Antarctica determined by satellite gravity and seismic models |
topic_facet |
Structural geology Geological structures Geophysical applications Glacial Isostatic Adjustments Gravitational model Mid oceanic ridges Numerical results Satellite gravity Spatial resolution Seismology Geophysics Geofysik |
description |
As recovering the crust-mantle/Moho density contrast (MDC) significantly depends on the properties of the Earth’s crust and upper mantle, varying from place to place, it is an oversimplification to define a constant standard value for it. It is especially challenging in Antarctica, where almost all the bedrock is covered with a thick layer of ice, and seismic data cannot provide a sufficient spatial resolution for geological and geophysical applications. As an alternative, we determine the MDC in Antarctica and its surrounding seas with a resolution of 1°x 1° by the Vening Meinesz-Moritz gravimetric-isostatic technique using the XGM2019e Earth Gravitational Model and Earth2014 topographic/bathymetric information along with CRUST1.0 and CRUST19 seismic crustal models. The numerical results show that our model, named HVMDC20, varies from 81 kg m-3 in the Pacific Antarctic mid-oceanic ridge to 579 kg m-3 in the Gamburtsev Mountain Range in the central continent with a general average of 403 kg m-3. To assess our computations, we compare our estimates with those of some other gravimetric as well as seismic models (KTH11, GEMMA12C, KTH15C and CRUST1.0), illustrating that our estimates agree fairly well with KTH15C and CRUST1.0 but rather poor with the other models. In addition, we compare the geological signatures with HVMDC20, showing how the main geological structures contribute to the MDC. Finally, we study the remaining glacial isostatic adjustment effect on gravity to figure out how much it affects the MDC recovery, yielding a correlation of the optimum spectral window (7< n <12) between XGM2019e and W12a GIA models of the order of ~0.6 contributing within a negligible \pm 14 kg m-3 to the MDC. This study was supported by project no. 187/18 of the Swedish National Space Agency (SNSA) |
format |
Article in Journal/Newspaper |
author |
Abrehdary, Majid Sjöberg, Lars |
author_facet |
Abrehdary, Majid Sjöberg, Lars |
author_sort |
Abrehdary, Majid |
title |
Moho density contrast in Antarctica determined by satellite gravity and seismic models |
title_short |
Moho density contrast in Antarctica determined by satellite gravity and seismic models |
title_full |
Moho density contrast in Antarctica determined by satellite gravity and seismic models |
title_fullStr |
Moho density contrast in Antarctica determined by satellite gravity and seismic models |
title_full_unstemmed |
Moho density contrast in Antarctica determined by satellite gravity and seismic models |
title_sort |
moho density contrast in antarctica determined by satellite gravity and seismic models |
publisher |
Högskolan Väst, Avdelningen för Matematik, Data- och Lantmäteriteknik |
publishDate |
2021 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-17514 https://doi.org/10.1093/gji/ggab069 |
geographic |
Antarctic Pacific |
geographic_facet |
Antarctic Pacific |
genre |
Antarc* Antarctic Antarctica |
genre_facet |
Antarc* Antarctic Antarctica |
op_relation |
Geophysical Journal International, 0956-540X, 2021, 225:3, s. 1952-1962 orcid:0000-0001-7810-8829 http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-17514 doi:10.1093/gji/ggab069 Scopus 2-s2.0-85114994287 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1093/gji/ggab069 |
container_title |
Geophysical Journal International |
container_volume |
225 |
container_issue |
3 |
container_start_page |
1952 |
op_container_end_page |
1962 |
_version_ |
1766079430431604736 |