The Souness Martian glacier-like forms - looking at the lowest and highest elevation objects
Tags: dissertation3D anaglyphMarsMartian glaciologyHiRISEMars Express HRSCDTM30 Nov 2016 - MawKernewek
Colin Souness, in his 2012 paper listed a total of 1309 'glacier-like forms' on the surface of Mars, in the mid-latitudes centred around 40° latitude, found from Mars Reconnaisance Orbiter context camera images.
In my dissertation (version for tablets) I studied descriptive statistics of them, including the distribution by elevation.
Since then, I have produced a web index to the objects, including a Top Trumps page for each object. I below show a table of links to the 30 Souness objects at the lowest and highest elevations. The Mars Express High Resolution Stereo Camera digital terrain model tile is shown where there is coverage, and it is also indicated where there are HiRISE images, or 3d anaglyphs that intersect with the outline of the object. These are linked to from the Top Trump page.
The elevation distribution looks as follows:
I noted in the dissertation that that the numbers of glaciers appeared to be depleted below elevations of -3000m relative to Mars datum. There are two types of explanation for this, firstly that they were not formed, or secondly that they were more rapidly ablated. Fewer may have formed in the range -5000 to -3000 due to slope effects, with a large proportion of the these elevations being made up of the flat plains in the northern hemisphere, and the Martian glaciers are preferentially found on slopes. Alternatively in the higher-obliquity epoch, ablation may have been favoured at low elevations, due to higher temperatures, and possibly wind-stripping of debris cover allowing sublimation.
The outliers at the extreme ends of the elevation distribution may be of interest, since they may show something about what limited the distribution of Souness objects on Mars.
There is a secondary peak in the distribution at very low elevations. These could have formed at a later epoch at a lower obliquity in a cooler climate where glacier accumulation was only significant at the lowest elevations.
It is also an interesting question whether the objects at very high elevations formed at the same epoch as the main distribution, or whether these come from an older, more extreme obliquity epoch.
In my dissertation (version for tablets) I studied descriptive statistics of them, including the distribution by elevation.
Since then, I have produced a web index to the objects, including a Top Trumps page for each object. I below show a table of links to the 30 Souness objects at the lowest and highest elevations. The Mars Express High Resolution Stereo Camera digital terrain model tile is shown where there is coverage, and it is also indicated where there are HiRISE images, or 3d anaglyphs that intersect with the outline of the object. These are linked to from the Top Trump page.
The elevation distribution looks as follows:
 |
| Elevation histograms for Souness object extents and head areas, compared with the overall elevation distribution in the coverage of the HRSC DTM tiles used |
 |
| Slope histograms for Souness object extents and head areas, compared with the overall slope distribution in the coverage of the HRSC DTM tiles used |
 |
| Showing the ratio of the GLF distribution as a function of elevation and slope / elevation and slope distribution in the HRSC tiles for extents. |
 |
| The GLF distribution as a function of elevation / elevation distribution in the HRSC tiles for the head areas. |
 |
| The GLF distribution as a function of slope / slope distribution in the HRSC tiles for the head areas. |
The outliers at the extreme ends of the elevation distribution may be of interest, since they may show something about what limited the distribution of Souness objects on Mars.
There is a secondary peak in the distribution at very low elevations. These could have formed at a later epoch at a lower obliquity in a cooler climate where glacier accumulation was only significant at the lowest elevations.
It is also an interesting question whether the objects at very high elevations formed at the same epoch as the main distribution, or whether these come from an older, more extreme obliquity epoch.
Lowest and highest 30 Souness glacier-like forms
Based on mean elevation of 5km circular radius buffer (from Souness et al. 2012 paper)
Lowest elevation 30 GLFs (buffer mean from Souness catalog):
Highest elevation 30 GLFs (buffer mean from Souness catalog):
| Catalog number | Elevation (m) | Region | HRSC DTM tile | Centre Latitude | Centre Longitude | Area (sq. km) | N HiRISE footprints intersecting | N anaglyphs intersecting |
|---|---|---|---|---|---|---|---|---|
| 844 | 7681 | Tharsis | H0453_0000 | -40.65 | -92.24 | 9.01 | 1 | 0 |
| 845 | 6928 | Tharsis | H0266_0000 | -40.91 | -94.50 | 0.93 | 0 | 0 |
| 846 | 6784 | Tharsis | H0266_0000 | -40.93 | -94.52 | 0.88 | 0 | 0 |
| 848 | 6708 | Tharsis | H0266_0000 | -40.95 | -94.58 | 1.44 | 0 | 0 |
| 847 | 6662 | Tharsis | H0266_0000 | -40.95 | -94.56 | 1.60 | 0 | 0 |
| 82 | 5894 | Olympus Mons and surrounding area | none | 41.69 | -110.67 | 1.16 | 0 | 0 |
| 850 | 5407 | Tharsis | H0508_0000 | -40.90 | -97.60 | 1.00 | 0 | 0 |
| 849 | 5301 | Tharsis | H0508_0000 | -40.81 | -97.94 | 0.81 | 0 | 0 |
| 851 | 5101 | Tharsis | H0508_0000 | -40.92 | -97.49 | 1.02 | 0 | 0 |
| 852 | 4556 | Tharsis | H0508_0000 | -41.85 | -97.55 | 1.22 | 1 | 0 |
| 853 | 4445 | Tharsis | H0508_0000 | -41.86 | -97.49 | 1.13 | 1 | 0 |
| 81 | 4139 | Olympus Mons and surrounding area | H5405_0000 | 44.92 | -111.19 | 3.29 | 0 | 0 |
| 827 | 4101 | Tharsis | H4087_0000 | -35.01 | -79.64 | 1.01 | 0 | 0 |
| 79 | 3927 | Olympus Mons and surrounding area | none | 38.33 | -103.58 | 0.67 | 1 | 0 |
| 823 | 3799 | Tharsis | H2596_0001 | -35.48 | -75.24 | 4.97 | 0 | 0 |
| 818 | 3769 | Tharsis | none | -36.62 | -70.77 | 4.20 | 1 | 0 |
| 854 | 3762 | Tharsis | none | -42.32 | -98.61 | 0.84 | 0 | 0 |
| 866 | 3675 | Tharsis | H4234_0000 | -42.08 | -124.73 | 7.10 | 0 | 0 |
| 817 | 3626 | Tharsis | none | -36.60 | -70.54 | 4.60 | 1 | 0 |
| 1034 | 3533 | East of Hellas | H2356_0002 | -40.83 | 103.02 | 20.49 | 2 | 1 |
| 794 | 3475 | Argyre | none | -50.59 | -58.61 | 10.56 | 0 | 0 |
| 1287 | 3444 | East of Hellas | H2279_0001 | -42.76 | 108.15 | 9.71 | 0 | 0 |
| 825 | 3441 | Tharsis | H2607_0000 | -41.95 | -76.95 | 1.47 | 0 | 0 |
| 819 | 3433 | Tharsis | none | -36.61 | -70.47 | 1.57 | 1 | 0 |
| 764 | 3404 | Argyre | H2669_0000 | -38.90 | -48.01 | 3.90 | 1 | 0 |
| 859 | 3210 | Tharsis | H2644_0000 | -49.59 | -113.36 | 8.60 | 0 | 0 |
| 824 | 3196 | Tharsis | H2640_0000 | -41.49 | -77.02 | 13.87 | 1 | 0 |
| 862 | 3188 | Tharsis | H0424_0000 | -43.42 | -121.98 | 4.31 | 0 | 0 |
| 1043 | 3155 | East of Hellas | H0451_0000 | -37.89 | 103.38 | 17.29 | 2 | 1 |
| 998 | 3134 | East of Hellas | H1887_0000 | -42.03 | 109.59 | 38.62 | 0 | 0 |
Based on mean HRSC DTM elevation of immediate head area (100m radius)
Lowest elevation 30 GLFs (head):
| Catalog number | Head elevation (m) | Termimus elevation (m) | Region | HRSC DTM tile | Head Latitude | Head Longitude | Area (sq. km) | N HiRISE footprints intersecting | N anaglyphs intersecting |
|---|---|---|---|---|---|---|---|---|---|
| 1130 | -6858 | -7173 | West of Hellas | H2613_0000 | -32.50 | 56.65 | 5.63 | 0 | 0 |
| 1119 | -6667 | -6943 | East of Hellas | H2195_0000 | -44.27 | 83.58 | 2.85 | 0 | 0 |
| 1120 | -6639 | -6918 | East of Hellas | H2195_0000 | -44.30 | 83.60 | 2.92 | 0 | 0 |
| 1118 | -5779 | -6047 | East of Hellas | H2631_0001 | -42.70 | 85.99 | 1.35 | 0 | 0 |
| 1117 | -5550 | -5647 | East of Hellas | H2631_0001 | -39.83 | 86.17 | 0.70 | 0 | 0 |
| 1301 | -5550 | -5663 | East of Hellas | H2631_0001 | -39.83 | 86.16 | 0.75 | 0 | 0 |
| 1302 | -5430 | -5659 | East of Hellas | H2631_0001 | -39.84 | 86.13 | 0.84 | 1 | 0 |
| 198 | -5251 | -5718 | Utopia Planitia and Phlegra Montes | H1526_0000 | 38.90 | 116.38 | 1.99 | 3 | 1 |
| 1300 | -5180 | -5595 | East of Hellas | H2631_0001 | -39.21 | 86.18 | 18.47 | 0 | 0 |
| 1113 | -5050 | 0 | East of Hellas | H0365_0000 | -40.99 | 90.17 | 0.61 | 1 | 0 |
| 200 | -4996 | -5782 | Utopia Planitia and Phlegra Montes | H1526_0000 | 39.08 | 116.04 | 3.62 | 1 | 0 |
| 1115 | -4937 | -5051 | East of Hellas | H2609_0000 | -38.19 | 88.07 | 4.74 | 0 | 0 |
| 1112 | -4934 | 0 | East of Hellas | H0365_0000 | -40.97 | 90.19 | 2.05 | 1 | 0 |
| 199 | -4927 | -5397 | Utopia Planitia and Phlegra Montes | H1526_0000 | 39.05 | 116.04 | 0.59 | 1 | 0 |
| 1114 | -4912 | -5228 | East of Hellas | H2609_0000 | -38.22 | 88.10 | 2.24 | 0 | 0 |
| 1116 | -4861 | -5262 | East of Hellas | H2609_0000 | -38.65 | 87.98 | 8.01 | 0 | 0 |
| 1111 | -4775 | -5282 | East of Hellas | H0365_0000 | -40.61 | 90.25 | 3.07 | 0 | 0 |
| 1103 | -4691 | -5009 | East of Hellas | H0528_0000 | -38.55 | 94.34 | 2.00 | 2 | 1 |
| 1 | -4222 | -4534 | Deuteronilus Mensae | H5314_0000 | 37.89 | -5.93 | 10.95 | 3 | 1 |
| 2 | -4149 | -4530 | Deuteronilus Mensae | H5314_0000 | 37.99 | -5.96 | 18.95 | 3 | 1 |
| 1110 | -4037 | -4049 | East of Hellas | H0550_0000 | -36.50 | 90.18 | 0.84 | 0 | 0 |
| 6 | -3805 | -4014 | Deuteronilus Mensae | H1498_0000 | 30.59 | -11.34 | 2.79 | 1 | 0 |
| 192 | -3772 | -4407 | Utopia Planitia and Phlegra Montes | H1317_0000 | 34.24 | 144.32 | 4.39 | 2 | 0 |
| 3 | -3746 | -4196 | Deuteronilus Mensae | H3253_0000 | 38.32 | -9.78 | 2.41 | 0 | 0 |
| 120 | -3691 | -3845 | Olympus Mons and surrounding area | H1258_0001 | 34.22 | -177.33 | 4.71 | 0 | 0 |
| 121 | -3684 | -4010 | Olympus Mons and surrounding area | H1258_0001 | 34.22 | -177.33 | 6.58 | 0 | 0 |
| 4 | -3677 | -3914 | Deuteronilus Mensae | H3253_0000 | 38.27 | -9.31 | 1.35 | 0 | 0 |
| 5 | -3604 | -4058 | Deuteronilus Mensae | H3253_0000 | 40.04 | -10.36 | 2.50 | 0 | 0 |
| 299 | -3447 | -3681 | Nilosyrtis Mensae | H1629_0000 | 42.47 | 62.49 | 1.40 | 0 | 0 |
| 1299 | -3393 | -4112 | East of Hellas | H0550_0000 | -35.30 | 91.18 | 1.65 | 7 | 1 |
Highest elevation 30 GLFs (head):
| Catalog number | Head elevation (m) | Termimus elevation (m) | Region | HRSC DTM tile | Head Latitude | Head Longitude | Area (sq. km) | N HiRISE footprints intersecting | N anaglyphs intersecting |
|---|---|---|---|---|---|---|---|---|---|
| 844 | 7484 | 7166 | Tharsis | H0453_0000 | -40.63 | -92.20 | 9.01 | 1 | 0 |
| 848 | 7078 | 6647 | Tharsis | H0266_0000 | -40.94 | -94.59 | 1.44 | 0 | 0 |
| 847 | 6980 | 6616 | Tharsis | H0266_0000 | -40.94 | -94.57 | 1.60 | 0 | 0 |
| 845 | 6971 | 6730 | Tharsis | H0266_0000 | -40.90 | -94.51 | 0.93 | 0 | 0 |
| 846 | 6959 | 6679 | Tharsis | H0266_0000 | -40.92 | -94.53 | 0.88 | 0 | 0 |
| 849 | 5624 | 5096 | Tharsis | H0508_0000 | -40.80 | -97.93 | 0.81 | 0 | 0 |
| 850 | 5439 | 4826 | Tharsis | H0508_0000 | -40.88 | -97.60 | 1.00 | 0 | 0 |
| 851 | 5190 | 4766 | Tharsis | H0508_0000 | -40.91 | -97.49 | 1.02 | 0 | 0 |
| 852 | 4822 | 4204 | Tharsis | H0508_0000 | -41.83 | -97.55 | 1.22 | 1 | 0 |
| 853 | 4566 | 4025 | Tharsis | H0508_0000 | -41.84 | -97.50 | 1.13 | 1 | 0 |
| 827 | 4183 | 3695 | Tharsis | H4087_0000 | -35.00 | -79.64 | 1.01 | 0 | 0 |
| 81 | 3914 | 3587 | Olympus Mons and surrounding area | H5405_0000 | 44.91 | -111.21 | 3.29 | 0 | 0 |
| 866 | 3797 | 3217 | Tharsis | H4234_0000 | -42.05 | -124.71 | 7.10 | 0 | 0 |
| 823 | 3729 | 3628 | Tharsis | H2596_0001 | -35.44 | -75.27 | 4.97 | 0 | 0 |
| 1287 | 3634 | 1951 | East of Hellas | H2279_0001 | -42.82 | 108.19 | 9.71 | 0 | 0 |
| 764 | 3627 | 2737 | Argyre | H2669_0000 | -38.89 | -48.06 | 3.90 | 1 | 0 |
| 825 | 3529 | 2918 | Tharsis | H2607_0000 | -41.93 | -76.97 | 1.47 | 0 | 0 |
| 1043 | 3367 | 752 | East of Hellas | H0451_0000 | -37.81 | 103.39 | 17.29 | 2 | 1 |
| 862 | 3317 | 2847 | Tharsis | H0424_0000 | -43.40 | -121.99 | 4.31 | 0 | 0 |
| 859 | 3249 | 1968 | Tharsis | H2644_0000 | -49.55 | -113.33 | 8.60 | 0 | 0 |
| 1034 | 3225 | -175 | East of Hellas | H2356_0002 | -40.70 | 103.01 | 20.49 | 2 | 1 |
| 863 | 3100 | 2827 | Tharsis | H0424_0000 | -43.42 | -122.02 | 4.36 | 0 | 0 |
| 826 | 3042 | 2691 | Tharsis | H2607_0000 | -41.92 | -76.89 | 2.57 | 0 | 0 |
| 1290 | 3013 | 1087 | East of Hellas | H2356_0002 | -41.71 | 104.12 | 21.98 | 1 | 0 |
| 822 | 2939 | 2606 | Tharsis | H2596_0001 | -37.19 | -72.32 | 0.92 | 0 | 0 |
| 824 | 2926 | 2282 | Tharsis | H2640_0000 | -41.48 | -77.12 | 13.87 | 1 | 0 |
| 861 | 2892 | 2332 | Tharsis | H2197_0001 | -51.24 | -113.67 | 2.04 | 0 | 0 |
| 1042 | 2825 | 1510 | East of Hellas | H0451_0000 | -37.83 | 103.32 | 4.63 | 2 | 1 |
| 1015 | 2800 | 569 | East of Hellas | H2345_0000 | -44.83 | 104.75 | 15.26 | 2 | 0 |
| 763 | 2780 | 2162 | Argyre | H2669_0000 | -38.54 | -48.03 | 1.12 | 0 | 0 |