canada chasm cliff current deluge descent drop fall flow gorge montane moss mountain natural nature opening pour river rock Rockies Rocky Mountains shade.shadow surge water abandoned Cornish cornwall desuetude distorted disused England english gnarled Great Britain heap mosses mossy old overgrown pile quarry rocks spoil stone stunted trees twisted boulders countryside fast flowing hillside Natural landscape Riparian zone spring stream water resources watercourse waterway woodland background bedding cone Dirt forest gray green ground leaf leaves litter mulch needle needles plant sand stick sticks stones texture tile twig twigs wallpaper