(a): The Sherman landslides fallen in Alaska in 1964. Courtesy USGS. (b): "La Perouse" landslide of April 2014, also in Alaska. Courtesy of NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Landsat data from the U.S. Geological Survey. (c): La Perouse landslide seen by airplane. Note the lobate shape, the flow following the local slope, and the longitudinal furrows. The short curvature radius of flow lines in correspondence of the turning point indicates that at that position the landslide was not travelling fast. Photo courtesy of FlyDrake Haines, Alaska.

(a): The Sherman landslides fallen in Alaska in 1964. Courtesy USGS. (b): "La Perouse" landslide of April 2014, also in Alaska. Courtesy of NASA Earth Observatory image by Jesse Allen and Robert Simmon, using Landsat data from the U.S. Geological Survey. (c): La Perouse landslide seen by airplane. Note the lobate shape, the flow following the local slope, and the longitudinal furrows. The short curvature radius of flow lines in correspondence of the turning point indicates that at that position the landslide was not travelling fast. Photo courtesy of FlyDrake Haines, Alaska.

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Landslides on Mars exhibit features such as steep collapse, extreme deposit thinning, and long runout. We study the flow dynamics of Martian landslides particularly in Valles Marineris, where landslides are among the largest and longest. Firstly, we observe that landslides in Valles Marineris share a series of features with terrestrial landslides f...

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Context 1
... confinement is often minimal or absent; however, some examples of channeled flow are observed. Figure 4 shows two landslides (more specifically, rock avalanches) fallen on Alaskan glaciers: the Sherman landslide ( fig. 4(a)) triggered by the 1964 Alaskan earthquake [23,24], and the recent La Perouse landslide, figs. ...
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... may reach the mentioned distance of several tens of km (as shown in figs. 1(d), 1(f) and 2(a), 2(c)) up to more than 100 km. Lateral confinement is often minimal or absent; however, some examples of channeled flow are observed. Figure 4 shows two landslides (more specifically, rock avalanches) fallen on Alaskan glaciers: the Sherman landslide ( fig. 4(a)) triggered by the 1964 Alaskan earthquake [23,24], and the recent La Perouse landslide, figs. 4(b), (c). Such rock avalanches travelling on glaciers typically exhibit apparent friction coefficient much lower than that on a rocky terrain [25][26][27], extreme stretching and flattening, longitudinal furrows following the lines of ...
Context 3
... landslide, figs. 4(b), (c). Such rock avalanches travelling on glaciers typically exhibit apparent friction coefficient much lower than that on a rocky terrain [25][26][27], extreme stretching and flattening, longitudinal furrows following the lines of inertial flow [28], and a lobate shape. The striking similarity between the landslides shown in fig. 4 and Martian landslides (figs. 1, 2) has been related to a similar glacial environment on Mars during their flow [1,2,13]. It has also been suggested that glaciers were present at the base of VM slope, since an observed slope break is attributed to a putative trimline marking the edge of a glacier [29]. ...
Context 4
... thank Paolo Frattini and Elena Valbuzzi for fruitful discussions. Drake Olson of FlyDrake Haines Alaska kindly gave us permission to reproduce the photograph of fig. ...

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... McEwen (1989) argued in favour of dry rock avalanches instead, and Lucchitta et al. (1992) suggested that they may have initiated as dry flows that incorporated water and ended up as mud flows. More generally, as for terrestrial landslides, several hypotheses have been proposed to explain the high mobility of Martian landslide such as fluidisation by liquid or gas in Valles Marineris (Harrison and Grimm 2003;Johnson and Campbell 2017), lubricating due to the presence of clays (Watkins et al. 2015) or ice (Lucchitta 1979(Lucchitta , 1981De Blasio 2011;Mazzanti et al. 2016;De Blasio and Crosta 2017;Crosta et al. 2018), the impact of seismic triggering with activation or reactivation of summital faults (Mège and Bourgeois 2011). Johnson and Campbell (2017) suggest on the contrary that Martian landslides may be less mobile than landslides on Earth, while Lucas et al. (2014) found no clear difference between empirical friction weakening with volume (or velocity) for terrestrial and Martian landslides. ...
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