Wet-Based Glaciation on Mars
Mars is a glacial planet. It hosts water ice in large polar ice caps, and in thousands of ‘viscous flow features’ in its mid latitudes that are thought to be debris-covered water ice glaciers. These ice deposits range between a few million to ~1 billion years in age and formed during Mars’ most rece...
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ftopenunivgb:oai:oro.open.ac.uk:60703 2023-06-11T04:10:59+02:00 Wet-Based Glaciation on Mars Butcher, Frances E. G. 2019-04-01 application/pdf application/msword https://oro.open.ac.uk/60703/ https://oro.open.ac.uk/60703/1/FRANCESBUTCHER_PHD_ETHESIS.pdf https://oro.open.ac.uk/60703/8/GRADPROG%20memo%20-%20DR%20%2B%20EdD_.doc https://oro.open.ac.uk/60703/9/thesis%20depo%20form.pdf https://oro.open.ac.uk/60703/16/Library%20deposition%20memo%20Butcher%202019-04-30.doc https://oro.open.ac.uk/60703/18/FRANCESBUTCHER_PHD_ETHESIS.pdf https://oro.open.ac.uk/60703/20/FRANCESBUTCHER_PHD_ETHESIS.pdf https://doi.org/10.21954/ou.ro.0000ed1f unknown https://oro.open.ac.uk/60703/1/FRANCESBUTCHER_PHD_ETHESIS.pdf https://oro.open.ac.uk/60703/8/GRADPROG%20memo%20-%20DR%20%2B%20EdD_.doc https://oro.open.ac.uk/60703/9/thesis%20depo%20form.pdf https://oro.open.ac.uk/60703/16/Library%20deposition%20memo%20Butcher%202019-04-30.doc https://oro.open.ac.uk/60703/18/FRANCESBUTCHER_PHD_ETHESIS.pdf https://oro.open.ac.uk/60703/20/FRANCESBUTCHER_PHD_ETHESIS.pdf Butcher, Frances E. G. <http://oro.open.ac.uk/view/person/fb3832.html> (2019). Wet-Based Glaciation on Mars. PhD thesis The Open University. Thesis Public NonPeerReviewed 2019 ftopenunivgb https://doi.org/10.21954/ou.ro.0000ed1f 2023-05-28T05:59:36Z Mars is a glacial planet. It hosts water ice in large polar ice caps, and in thousands of ‘viscous flow features’ in its mid latitudes that are thought to be debris-covered water ice glaciers. These ice deposits range between a few million to ~1 billion years in age and formed during Mars’ most recent epoch, the late Amazonian. The late Amazonian was characterised by extremely cold and arid climate conditions that are not conducive to melting of ice. Consequently, late-Amazonian glaciation has been dominated by cold-based glacier thermal regimes. However, the recent discovery of an esker (a ridge of sediment deposited by meltwater flowing through a tunnel within or beneath glacial ice) associated with a viscous flow feature in the Phlegra Montes region of Mars’ northern mid latitudes provided the first indicative evidence that wet-based glaciation occurred in at least one location during the late Amazonian. In this thesis, I present the discovery of a second candidate esker associated with a viscous flow feature, in the NW Tempe Terra region of Mars’ northern mid latitudes. I argue that the remarkably similar geologic settings of the NW Tempe Terra and Phlegra Montes candidate eskers (both within tectonic rift/graben valleys) suggests that geothermal heating, possibly with an additional component of viscous strain heating within the basal ice, was a prerequisite for basal melting under cold climate conditions. I then characterise the 2D and 3D morphometries of these candidate eskers, undertake comparisons with the morphometries of ancient putative eskers on Mars and eskers on Earth, and develop conceptual models for the dynamics of esker formation in NW Tempe Terra. Finally, I present a geomorphic map of Chukhung crater, Mars, which hosts esker-like sinuous ridges associated with viscous flow features and provides a case study of the ongoing challenges for esker identification on Mars. Thesis Cold-based glacier The Open University: Open Research Online (ORO) |
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Open Polar |
collection |
The Open University: Open Research Online (ORO) |
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ftopenunivgb |
language |
unknown |
description |
Mars is a glacial planet. It hosts water ice in large polar ice caps, and in thousands of ‘viscous flow features’ in its mid latitudes that are thought to be debris-covered water ice glaciers. These ice deposits range between a few million to ~1 billion years in age and formed during Mars’ most recent epoch, the late Amazonian. The late Amazonian was characterised by extremely cold and arid climate conditions that are not conducive to melting of ice. Consequently, late-Amazonian glaciation has been dominated by cold-based glacier thermal regimes. However, the recent discovery of an esker (a ridge of sediment deposited by meltwater flowing through a tunnel within or beneath glacial ice) associated with a viscous flow feature in the Phlegra Montes region of Mars’ northern mid latitudes provided the first indicative evidence that wet-based glaciation occurred in at least one location during the late Amazonian. In this thesis, I present the discovery of a second candidate esker associated with a viscous flow feature, in the NW Tempe Terra region of Mars’ northern mid latitudes. I argue that the remarkably similar geologic settings of the NW Tempe Terra and Phlegra Montes candidate eskers (both within tectonic rift/graben valleys) suggests that geothermal heating, possibly with an additional component of viscous strain heating within the basal ice, was a prerequisite for basal melting under cold climate conditions. I then characterise the 2D and 3D morphometries of these candidate eskers, undertake comparisons with the morphometries of ancient putative eskers on Mars and eskers on Earth, and develop conceptual models for the dynamics of esker formation in NW Tempe Terra. Finally, I present a geomorphic map of Chukhung crater, Mars, which hosts esker-like sinuous ridges associated with viscous flow features and provides a case study of the ongoing challenges for esker identification on Mars. |
format |
Thesis |
author |
Butcher, Frances E. G. |
spellingShingle |
Butcher, Frances E. G. Wet-Based Glaciation on Mars |
author_facet |
Butcher, Frances E. G. |
author_sort |
Butcher, Frances E. G. |
title |
Wet-Based Glaciation on Mars |
title_short |
Wet-Based Glaciation on Mars |
title_full |
Wet-Based Glaciation on Mars |
title_fullStr |
Wet-Based Glaciation on Mars |
title_full_unstemmed |
Wet-Based Glaciation on Mars |
title_sort |
wet-based glaciation on mars |
publishDate |
2019 |
url |
https://oro.open.ac.uk/60703/ https://oro.open.ac.uk/60703/1/FRANCESBUTCHER_PHD_ETHESIS.pdf https://oro.open.ac.uk/60703/8/GRADPROG%20memo%20-%20DR%20%2B%20EdD_.doc https://oro.open.ac.uk/60703/9/thesis%20depo%20form.pdf https://oro.open.ac.uk/60703/16/Library%20deposition%20memo%20Butcher%202019-04-30.doc https://oro.open.ac.uk/60703/18/FRANCESBUTCHER_PHD_ETHESIS.pdf https://oro.open.ac.uk/60703/20/FRANCESBUTCHER_PHD_ETHESIS.pdf https://doi.org/10.21954/ou.ro.0000ed1f |
genre |
Cold-based glacier |
genre_facet |
Cold-based glacier |
op_relation |
https://oro.open.ac.uk/60703/1/FRANCESBUTCHER_PHD_ETHESIS.pdf https://oro.open.ac.uk/60703/8/GRADPROG%20memo%20-%20DR%20%2B%20EdD_.doc https://oro.open.ac.uk/60703/9/thesis%20depo%20form.pdf https://oro.open.ac.uk/60703/16/Library%20deposition%20memo%20Butcher%202019-04-30.doc https://oro.open.ac.uk/60703/18/FRANCESBUTCHER_PHD_ETHESIS.pdf https://oro.open.ac.uk/60703/20/FRANCESBUTCHER_PHD_ETHESIS.pdf Butcher, Frances E. G. <http://oro.open.ac.uk/view/person/fb3832.html> (2019). Wet-Based Glaciation on Mars. PhD thesis The Open University. |
op_doi |
https://doi.org/10.21954/ou.ro.0000ed1f |
_version_ |
1768385766506889216 |