geological structure above walensee, switzerland

walensee st gallen switzerland schweiz alpensee alpine lake glarus alpen alps ferien wandern hiking tourism tourismus swiss holiday cliffs wanderweg wanderung betliserstrasse amden quinten geological formations rocks amdenformation leistmergel schiefer shale mergel sediment schichtgestein sedimentgestein sedimentary rock geology of the gestein ablagerungen meeresboden gebirgshebung mountain elevation