Gravity‐Derived Antarctic Crustal Thickness Based on the Gauss‐FFT Method

Abstract The information on crustal thickness in Antarctica can provide significant constraints on its crustal deformation and tectonic evolution. To generate reliable images of crustal features, we investigate the model of Moho depth and crustal thickness beneath Antarctica by applying the Bott‐Par...

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Main Authors: Fei Ji, Leyuan Wu, Qiao Zhang
Format: Article
Language:English
Published: Wiley 2022-08-01
Series:Geochemistry, Geophysics, Geosystems
Online Access:https://doi.org/10.1029/2022GC010555
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author Fei Ji
Leyuan Wu
Qiao Zhang
author_facet Fei Ji
Leyuan Wu
Qiao Zhang
author_sort Fei Ji
collection DOAJ
description Abstract The information on crustal thickness in Antarctica can provide significant constraints on its crustal deformation and tectonic evolution. To generate reliable images of crustal features, we investigate the model of Moho depth and crustal thickness beneath Antarctica by applying the Bott‐Parker's formulas based on the Gauss‐fast Fourier transform method through a comprehensive analysis of gravity data, ice and sediment thicknesses and bedrock elevation, combined with seismic constraints. Tests with synthetic data indicate that the iterative inversion algorithm can yield a highly accurate Moho topography. Ultimately, inverted crustal thickness reveals a more detailed crustal image by clearly identifying more tectonic elements at different scales than previous results and correlates well with major tectonic provinces. Airy isostasy and flexural isostasy models are used to assess the crustal isostatic compensation. The distinctive negative isostatic anomalies are observed in the Transantarctic Mountains and the East Antarctic areas of the great escarpment in the Dronning Maud Land and Aurora and Wilkes Subglacial Basin, indicating that the low density of the uppermost mantle and lithospheric strength may play important roles in compensating for their elevations. Variations in crustal thickness in interior East Antarctica are analyzed; the thickened crust from Dronning Maud Land to the Gamburtsev Subglacial Mountains may be associated with the collision of continental blocks and is interpreted as the fossil sutures. We compare the relationship between the Moho and Curie interfaces and find that the uppermost mantle is magnetized in some areas of East Antarctica, which may indicate preserved Precambrian cratonic roots.
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series Geochemistry, Geophysics, Geosystems
spelling doaj-art-d8949d165e69446486f7ffb7fe72e2be2025-08-20T03:05:09ZengWileyGeochemistry, Geophysics, Geosystems1525-20272022-08-01238n/an/a10.1029/2022GC010555Gravity‐Derived Antarctic Crustal Thickness Based on the Gauss‐FFT MethodFei Ji0Leyuan Wu1Qiao Zhang2National Institute of Natural Hazards Ministry of Emergency Management of China Beijing ChinaKey Laboratory of Quantunm Precision Measurement of Zhejiang Province Center for Optics and Optoelectronics Research (COOR) Collaborative Innovation Center for Information Technology in Biological and Medical Physics College of Science Zhejiang University of Technology Hangzhou ChinaInstitute of Geomechanics Chinese Academy of Geological Sciences Beijing ChinaAbstract The information on crustal thickness in Antarctica can provide significant constraints on its crustal deformation and tectonic evolution. To generate reliable images of crustal features, we investigate the model of Moho depth and crustal thickness beneath Antarctica by applying the Bott‐Parker's formulas based on the Gauss‐fast Fourier transform method through a comprehensive analysis of gravity data, ice and sediment thicknesses and bedrock elevation, combined with seismic constraints. Tests with synthetic data indicate that the iterative inversion algorithm can yield a highly accurate Moho topography. Ultimately, inverted crustal thickness reveals a more detailed crustal image by clearly identifying more tectonic elements at different scales than previous results and correlates well with major tectonic provinces. Airy isostasy and flexural isostasy models are used to assess the crustal isostatic compensation. The distinctive negative isostatic anomalies are observed in the Transantarctic Mountains and the East Antarctic areas of the great escarpment in the Dronning Maud Land and Aurora and Wilkes Subglacial Basin, indicating that the low density of the uppermost mantle and lithospheric strength may play important roles in compensating for their elevations. Variations in crustal thickness in interior East Antarctica are analyzed; the thickened crust from Dronning Maud Land to the Gamburtsev Subglacial Mountains may be associated with the collision of continental blocks and is interpreted as the fossil sutures. We compare the relationship between the Moho and Curie interfaces and find that the uppermost mantle is magnetized in some areas of East Antarctica, which may indicate preserved Precambrian cratonic roots.https://doi.org/10.1029/2022GC010555
spellingShingle Fei Ji
Leyuan Wu
Qiao Zhang
Gravity‐Derived Antarctic Crustal Thickness Based on the Gauss‐FFT Method
Geochemistry, Geophysics, Geosystems
title Gravity‐Derived Antarctic Crustal Thickness Based on the Gauss‐FFT Method
title_full Gravity‐Derived Antarctic Crustal Thickness Based on the Gauss‐FFT Method
title_fullStr Gravity‐Derived Antarctic Crustal Thickness Based on the Gauss‐FFT Method
title_full_unstemmed Gravity‐Derived Antarctic Crustal Thickness Based on the Gauss‐FFT Method
title_short Gravity‐Derived Antarctic Crustal Thickness Based on the Gauss‐FFT Method
title_sort gravity derived antarctic crustal thickness based on the gauss fft method
url https://doi.org/10.1029/2022GC010555
work_keys_str_mv AT feiji gravityderivedantarcticcrustalthicknessbasedonthegaussfftmethod
AT leyuanwu gravityderivedantarcticcrustalthicknessbasedonthegaussfftmethod
AT qiaozhang gravityderivedantarcticcrustalthicknessbasedonthegaussfftmethod