River meandering on Earth and Mars: A comparative study of Aeolis Dorsa meanders, Mars and possible terrestrial analogs of the Usuktuk River, AK, and the Quinn River, NV

Model for the Formation of Single‐Thread Rivers in Barren Landscapes and Implications for Pre‐Silurian and Martian Fluvial Deposits

“…Predicted W / h for terrestrial rivers using input parameters representative of (a) shallow rivers forming within muddy unvegetated banks ( h = 1 m; Q = Quinn River, NV, Matsubara et al, ; A = Amargosa River, CA, Ielpi, 2018a), (b) yet shallower rivers forming within largely plant‐devoid banks (B = washes of the Bonneville Basin, UT, Figure a, Ielpi & Lapôtre, ; T = streams of the Toiyabe Basin, NV, Ielpi & Lapôtre, ), (c) deep rivers ( h = 10 m) without modeled vegetation‐added bank strength, and (d) deep rivers ( h = 10 m) with modeled vegetation‐added bank strength ( σ * = 29). Table summarizes model input parameters for each panel and Table data from natural rivers.…”

“…Despite being rarely recognized (e.g., Gibling et al, ; Hartley et al, ; McMahon & Davies, ), at least some single‐thread rivers existed long before plants colonized land (Long, , ; Ielpi & Rainbird, ; Santos & Owen, ; Ielpi et al, , 2017). Moreover, some single‐thread rivers meander on Earth today in the virtual absence of macroscopic plant life (Matsubara et al, ; Ielpi, ; Ielpi & Lapôtre, ‐b; Santos et al, ). Finally, another barren endmember of single‐thread rivers comes from Mars.…”

Undersea river patterns

“…In part, this may reflect the absence of sediment required for true braiding. Reduced gravity -due to lower planetary mass -on Mars requires deeper flows for equivalent basal stresses, and enhances sediment suspension and thus also overbank sedimentation rates 9 . However, subaerial sediment-laden water flows are thought to have once flowed on Mars and were initially predicted to preferentially favour braiding, yet braided channels have not been observed on the Martian surface 7,9 . Intriguingly, the model used by Foreman et al for maintenance of submarine channels, and corresponding restriction of braiding, has analogies with a formation model postulated for the spectacular Aeolis Dorsa meanders on Mars 9 .…”

“…For example, channels on Mercury, Venus, the Moon and Io are postulated to have formed due to flowing lava 8 . In addition, salts are also are thought to contribute to the Martian meanders by encouraging flocculation and rapid deposition of muds 9 . Reduced gravity -due to lower planetary mass -on Mars requires deeper flows for equivalent basal stresses, and enhances sediment suspension and thus also overbank sedimentation rates 9 .…”

“…However, subaerial sediment-laden water flows are thought to have once flowed on Mars and were initially predicted to preferentially favour braiding, yet braided channels have not been observed on the Martian surface 7,9 . Intriguingly, the model used by Foreman et al for maintenance of submarine channels, and corresponding restriction of braiding, has analogies with a formation model postulated for the spectacular Aeolis Dorsa meanders on Mars 9 . In combination, reduced gravity and salt-induced flocculation are proposed to encourage rapid accretion of cohesive banks, maintenance of channel width, and stabilisation of meandering planforms 9 . In addition, salts are also are thought to contribute to the Martian meanders by encouraging flocculation and rapid deposition of muds 9 .…”