gloppedalsura magma geopark stavanger norway

100 240 altitude annual area avalanche away boulders broke burrowed byrkjedal byrkjedalsgryta consists course covered cycle dammed debris evidence expanding formed former free frost geopark gilja giljajuvet gloppedalsura gully hunnedal ice lake magma massive melted metre metres moraine mountainside norway number outlet period piled river rocks scree settled sheet southern stavanger terraces thick time towards tumbling vast veen vikesayen water