Glacier-like Forms

Souness and others (2012). An inventory and population-scale analysis of martian glacier-like forms. Icarus 217(1), 243-255.

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Remark: Glacier-like Forms surveyed on 8058 CTX images in Mars’ mid-latitudes (25–65° north and south).

Definition: To be classified as a GLF in this survey, a feature was required to comply with all of the following conditions. A GLF must:

  1. Be surrounded by topography, showing general evidence of flow over or around obstacles.
  2. Be distinct from the surrounding landscape, exhibiting a texture or colour different from adjacent terrains.
  3. Display surface foliation indicative of down-slope flow; e.g. compressional/extensional ridges, surface lineations or arcuate surface morphologies or surface crevassing.
  4. Have a length to width ratio > 1 (i.e. be longer than it is wide), and thus be distinct from the apron-like LDA class of feature.
  5. Have either a discernable ‘head’ or a discernable ‘terminus’ indicating a compositional boundary or process threshold.
  6. Appear to contain a volume of ice (or some other viscous substance), having a relatively flat ‘valley fill’ surface (Fig. 1b), thus differentiating it from a previously glaciated ‘GLF skeleton’ or assemblage of post-glacial type landforms.”

Significance GLFs presently occur where icy material, preferentially distributed within well-defined latitudinal and elevational ranges, has undergone local, gravity-induced flow and deformation in response to local relief. and Martian GLFs may not exhibit accumulation areas or ablation areas as exist on Earth.
Comment All GLFs (with a few duplicates removed). The GLF’s ID number is important as we have referred to several by their number.

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