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Loose or fragmented rock

There are more than scree that consist of loose or fragmented rock, I have seen that natural=scree sometimes is used for features that are not exactly scree (accumulation of broken rock fragments at the base of degrading rock slopes/cliffs).

areas of boulder/stones/gravel can have many names like: boulder field, block field, stone run, et.c.

One possible solution for these other areas could be to use:

natural=bare_rock a feature in the draft Proposed features/bare rock

+ fragmented=yes

some other suggestions is:

natural=fragmented_rock or loose_rock

  • Just seen this and agree that we need ways to separate one of more of the following: stone run [W] Stone Run, block field [W] Block Field, stone glaciers [W] Rock Glacier and boulder fields. I don't think bare_rock should be used: these are all loose rocks or rocks detached from the main bedrock, whereas natural=bare_rock usually refers to what the geologists call solid. SK53 (talk) 15:47, 11 January 2015 (UTC)
In the discussion on the Polish forum, it was thought that this is also the best tag to map "stone run", with addition tag scree=stone_run --Władysław Komorek (talk) 22:40, 16 November 2018 (UTC)
For hiking and mountaineering navigation I think it is critical to differentiate the size and stability of the rocks in some way. Large stable rocks (in Canada we call this talus) are easy and efficient to ascend. Small unstable pebbles (scree in Canada) make for a painstaking ascent, since you slip downhill half the distance of every step up. But on the way down these slopes are glorious as you can literally run down the mountain. Slopes with large unstable loose rocks are just plain dangerous and best to avoid. natural=scree currently includes all 3 of these cases. natural=beach uses surface=sand, pebblestone, etc but there don't seem to be any options for cobble / boulder beaches. There is also smoothness=* ScottNelson (talk) 04:46, 15 April 2019 (UTC)
For fine scree you can use surface=fine_gravel, surface=gravel, or surface=pebbles depending on the particle size. While these values are not as common, there are already uses of surface=stones for mid-sized stones (i.e. cobbles - could also use "cobblestone"), and surface=boulders for larger boulders ("In geology, a boulder is a rock fragment with size greater than 25.6 centimetres (10.1 in) in diameter."). If the boulders are so large that they cannot move, (>1 meter diameter perhaps?), I think most mappers use natural=bare_rock --Jeisenbe (talk) 23:52, 11 November 2019 (UTC)