Over a long period of time, sufficient material can accumulate in this way to produce a distinct bank of stony material which, long after the snowbed has melted away, remains as a rampart (a bank or mound similar to a manmade rampart).
The morphology of the site may also suggest it being unfavourable for the development of a glacier, but suitable for this mechanism.
[1] Protalus ramparts are recorded in the Cairngorms and northwest Highlands of Scotland.
An especially large example on the north side of Baosbheinn measures 1 km in length and reaches a height of 55 m. It is thought to result from a major rock slope failure, however evidence leads some to class it as a protalus rock glacier.
[2][3][4] Several features amongst the mountains of the Brecon Beacons National Park have been interpreted by some authors as protalus ramparts but as moraines by others.