Erosion by tectonic carving in the Concordia Subglacial Fault Zone, East Antarctica
In this work we present the analysis of the footwall morphology of the Concordia subglacial extensional fault in the East Antarctic Craton. The Concordia Fault is a regional fault zone that extends for almost 200 km. The displacement, up to 1800 m, and the listric geometry were recognized by numeric...
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ftunivgenova:oai:iris.unige.it:11567/988367 2024-02-11T09:57:37+01:00 Erosion by tectonic carving in the Concordia Subglacial Fault Zone, East Antarctica MAGGI, MATTEO CIANFARRA, Paola SALVINI, Francesco Maggi, Matteo Cianfarra, Paola Salvini, Francesco 2016 ELETTRONICO http://hdl.handle.net/11567/988367 https://doi.org/10.1016/j.epsl.2015.10.045 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000367120300010 volume:433 firstpage:99 lastpage:108 numberofpages:10 journal:EARTH AND PLANETARY SCIENCE LETTERS http://hdl.handle.net/11567/988367 doi:10.1016/j.epsl.2015.10.045 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84946423168 info:eu-repo/semantics/closedAccess info:eu-repo/semantics/article 2016 ftunivgenova https://doi.org/10.1016/j.epsl.2015.10.045 2024-01-17T18:01:30Z In this work we present the analysis of the footwall morphology of the Concordia subglacial extensional fault in the East Antarctic Craton. The Concordia Fault is a regional fault zone that extends for almost 200 km. The displacement, up to 1800 m, and the listric geometry were recognized by numerical modeling of the resulting hangingwall bedrock morphology and is responsible for the marked asymmetry that characterizes the corresponding scarp in the Concordia Subglacial Trench. The portion of the footwall in the proximity of the master fault exhibits an excavated morphology, about 500 m deep and up to 5 km wide, showing strong correlation with the master fault displacement. We excluded a predominant glacial and fluvial origin of this morphology considering: (i) the sharp topography of the Concordia Fault, suggesting that the fault activity started after the onset of the ice sheet; (ii) the ice-sheet/bedrock contact is characterized by a general negligible erosion/deposition rates still allowing clast removal; (iii) the lack of significant deposits in the Concordia Trench. We hence explored the possibility that this morphology may result from the combined action of fault-induced fracturing and passive clast removal and scattering by flow and plastic deformation within the ice sheet. We introduced the term tectonic carving for this process. Our modeling shows that tectonic carving relates to the relative fracture intensity in the Concordia fracture zone, that corresponds to the envelope of master and secondary fault damage zones. Fracture intensity depends on the frequency and the displacement of secondary faulting and can be approximated by a normal distribution. Using a Monte Carlo modeling approach we selected the set of parameters that best fits the data set with the carving theoretical curve. The final results of the Monte Carlo analysis show a root mean square of about 50 meters, comparable with the data resolution. This analysis demonstrates a method to unravel the presence of fracture zones in similar, ... Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica Ice Sheet Università degli Studi di Genova: CINECA IRIS Antarctic East Antarctica Earth and Planetary Science Letters 433 99 108 |
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Open Polar |
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Università degli Studi di Genova: CINECA IRIS |
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English |
description |
In this work we present the analysis of the footwall morphology of the Concordia subglacial extensional fault in the East Antarctic Craton. The Concordia Fault is a regional fault zone that extends for almost 200 km. The displacement, up to 1800 m, and the listric geometry were recognized by numerical modeling of the resulting hangingwall bedrock morphology and is responsible for the marked asymmetry that characterizes the corresponding scarp in the Concordia Subglacial Trench. The portion of the footwall in the proximity of the master fault exhibits an excavated morphology, about 500 m deep and up to 5 km wide, showing strong correlation with the master fault displacement. We excluded a predominant glacial and fluvial origin of this morphology considering: (i) the sharp topography of the Concordia Fault, suggesting that the fault activity started after the onset of the ice sheet; (ii) the ice-sheet/bedrock contact is characterized by a general negligible erosion/deposition rates still allowing clast removal; (iii) the lack of significant deposits in the Concordia Trench. We hence explored the possibility that this morphology may result from the combined action of fault-induced fracturing and passive clast removal and scattering by flow and plastic deformation within the ice sheet. We introduced the term tectonic carving for this process. Our modeling shows that tectonic carving relates to the relative fracture intensity in the Concordia fracture zone, that corresponds to the envelope of master and secondary fault damage zones. Fracture intensity depends on the frequency and the displacement of secondary faulting and can be approximated by a normal distribution. Using a Monte Carlo modeling approach we selected the set of parameters that best fits the data set with the carving theoretical curve. The final results of the Monte Carlo analysis show a root mean square of about 50 meters, comparable with the data resolution. This analysis demonstrates a method to unravel the presence of fracture zones in similar, ... |
author2 |
Maggi, Matteo Cianfarra, Paola Salvini, Francesco |
format |
Article in Journal/Newspaper |
author |
MAGGI, MATTEO CIANFARRA, Paola SALVINI, Francesco |
spellingShingle |
MAGGI, MATTEO CIANFARRA, Paola SALVINI, Francesco Erosion by tectonic carving in the Concordia Subglacial Fault Zone, East Antarctica |
author_facet |
MAGGI, MATTEO CIANFARRA, Paola SALVINI, Francesco |
author_sort |
MAGGI, MATTEO |
title |
Erosion by tectonic carving in the Concordia Subglacial Fault Zone, East Antarctica |
title_short |
Erosion by tectonic carving in the Concordia Subglacial Fault Zone, East Antarctica |
title_full |
Erosion by tectonic carving in the Concordia Subglacial Fault Zone, East Antarctica |
title_fullStr |
Erosion by tectonic carving in the Concordia Subglacial Fault Zone, East Antarctica |
title_full_unstemmed |
Erosion by tectonic carving in the Concordia Subglacial Fault Zone, East Antarctica |
title_sort |
erosion by tectonic carving in the concordia subglacial fault zone, east antarctica |
publishDate |
2016 |
url |
http://hdl.handle.net/11567/988367 https://doi.org/10.1016/j.epsl.2015.10.045 |
geographic |
Antarctic East Antarctica |
geographic_facet |
Antarctic East Antarctica |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000367120300010 volume:433 firstpage:99 lastpage:108 numberofpages:10 journal:EARTH AND PLANETARY SCIENCE LETTERS http://hdl.handle.net/11567/988367 doi:10.1016/j.epsl.2015.10.045 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84946423168 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1016/j.epsl.2015.10.045 |
container_title |
Earth and Planetary Science Letters |
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433 |
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99 |
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108 |
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1790593157646254080 |