basalt rock columns and glacial river at studlagil canyon near jokuldalur, east iceland

aluminium aphanitic autumn basalt column beautiful canyon cliff columnar columns cooling curved dangerous dramatic duncan brown twisted egilsstadir environment extrusion extrusive flowing formation geology glacial glacier gorge halslon heat highlands hydroelectric hálslón iceland igneous rock iron jokuldalur karahnjukavirkjun lava low-viscosity mafic magnesium metamorphic pillar pillars reydarfjordur river studlafoss studlagil stuðlagil valley