I was particularly struck by this image which I copied when I was trawling about the other day, showing the northern flank of the Daugaard-Jensen Glacier -- a huge outlet glacier draining the Greenland Ice Sheet into Nordvestfjord. This is a relatively stable glacier which has a very rapid discharge rate -- it moves at almost 3 km per per year, which is comparable to the velocity intermittently affecting smaller surging glaciers. About 10 cubic kilometres of ice are discharged into the fjord every year.
The 5 km wide snout has maintained a relatively stable position over recent decades, and this means that the ice edge positionh in the glacier torough is also relatively stable. This of course favours the creation of lateral morainic ridges, and on the image above we can see a fine continuous marginal moraine extending all the way to the snout.
What intrigues me particularly is the creation of kame terraces in the elongated ice marginal lake on the glacier side of the moraine. This goes some way to explaining the pecular features observed on the valley sides of Kaldalon, in NW Iceland. See my post:
https://brian-mountainman.blogspot.com/2025/12/how-kaldalon-kames-are-formed.html
Maybe they are not so peculiar after all!
I am not sure what englacial and subglacial meltwater conduits there may be on this lower part of the DJ Glacier. But it's clear that the composition and bedding of the morainic ridge and the terraces must be highly variable, with the additional incorporation of rockfall debris from the valley sides and also debris from the alluvial fans linked to steep gullies high up on the mountainside.
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Note: the ice velocity in the Daugaard-Jensen Glacier may seem spectacular, but it pales into insignificance when copmpared with the Jacobshavn Isbrae in West Greebland, where velocities of up to 18 km per year have been measured.
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