Morphometry of a glacier-linked esker in NW Tempe Terra, Mars, and implications for sediment-discharge dynamics of subglacial drainage

Butcher, Frances E. G.; Balme, Matthew R.; Conway, Susan J.; Gallagher, Colman; Arnold, Neil S.; Storrar, Robert D.; Lewis, Stephen R. and Hagermann, Axel (2020). Morphometry of a glacier-linked esker in NW Tempe Terra, Mars, and implications for sediment-discharge dynamics of subglacial drainage. Earth and Planetary Science Letters, 542, article no. 116325.

DOI: https://doi.org/10.1016/j.epsl.2020.116325

Abstract

We present a systematic, metre-scale characterisation of the 3D morphometry of an esker on Mars, and the first attempt to reconstruct the multi-stage dynamics of esker formation on Mars. Eskers are sinuous ridges comprising sediment deposited by meltwater draining through ice-confined tunnels within or beneath glaciers. Detailed morphometric insights into eskers on Mars are important for (i) informing morphometric tests of whether sinuous ridges elsewhere on Mars are eskers, and (ii) informing modelling experiments that aim to reconstruct the glaciological and environmental controls on esker formation on Mars. We use a digital elevation model generated from High Resolution Imaging Science Experiment (HiRISE) images to characterise the height and width of an extremely rare esker associated with a late-Amazonian-aged viscous flow feature (debris-covered glacier) in NW Tempe Terra, Mars. Our measurements suggest that the NW Tempe Terra esker is a ‘stacked’ formation comprising an underlying ‘lower member’ ridge that is superposed by a narrower ‘upper member’ ridge. We used a novel morphometric approach to test whether the apparent stacking records two distinct esker deposition regimes (either within the same drainage episode, or within temporally-separated drainage episodes). This approach posits that esker crest morphology is controlled by primary esker formation processes and, by extension, that portions of eskers with similar crest morphologies should have similar morphometric relationships. We predicted the morphometric relationships described by the constituent upper and lower member ridges based on ‘reference relationships’ observed for morphologically-similar portions of the esker where no evidence of stacking was observed. Our observations corresponded well with the predicted relationships, supporting our stacked esker hypothesis. We propose conceptual models, which invoke spatial and temporal variations in sediment supply and meltwater discharge, to explain the stacked morphology. These models are informed by morpho-sedimentary relationships observed along eskers on Earth.

Viewing alternatives

Download history

Metrics

Public Attention

Altmetrics from Altmetric

Number of Citations

Citations from Dimensions

Item Actions

Export

About

  • Item ORO ID
  • 70495
  • Item Type
  • Journal Item
  • ISSN
  • 0012-821X
  • Project Funding Details
  • Funded Project NameProject IDFunding Body
    STFC DTG 2015 - 2016 (2015 Intake)ST/N50421X/1STFC (Science & Technology Facilities Council)
    Not SetNot SetThe Open University (OU)
    Not SetST/L00643X/1UK Space Agency (UKSA)
    Not SetST/R001413/1UK Space Agency (UKSA)
    Not SetST/R001383/1UK Space Agency (UKSA)
    Not SetST/R001405/1UK Space Agency (UKSA)
    Not SetST/P001262/1UK Space Agency (UKSA)
    Not SetST/S00145X/1UK Space Agency (UKSA)
    Not SetNot SetFrench Space Agency (CNES)
    ERC Advanced Grant PALGLAC787263European Research Council (ERC)
  • Keywords
  • Mars geomorphology; Glaciers on Mars; Wet-based glaciation; Esker; Glacial hydrology
  • Academic Unit or School
  • Faculty of Science, Technology, Engineering and Mathematics (STEM) > Physical Sciences
    Faculty of Science, Technology, Engineering and Mathematics (STEM)
  • Research Group
  • Space
  • Copyright Holders
  • © 2020 The Authors
  • Depositing User
  • Frances Butcher

Recommendations