Fjaðrárgljúfur - Fjadrá Canyon, Iceland
Fjaðrárgljúfur - (or: Fjaðrá Canyon, the Canyon where the Fjaðrá river runs through) is a rugged and impressive gorge, fairly wide, about 100 m deep and 2 km long. The gorge runs through hyoloclastite (soft granular rock) with lave layers and intrusions, the entire formation dating from the Ice age 2 million years ago.
Formation: When the ice cap retreated durin the last glacial period, a deep lake was formed in a valley above the present gorge, the water being retained behind a threshold of rock, with overflow water running down the slope now cut by the gorge. As rivers freed by the edge of the ice cap deposied a lot of sediment in the lake, the spill-water eroded the rock threshold and the hyaloclastite in from of it. The result was a powerful watercourse that cut the gorge we see today. Eventually it dwindled as the lake filled up and the river cut its way lower and lower into the sediment in the valley.
(Cited from an information sign at the location)
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Fjaðrárgljúfur - Fjadrá Canyon, Iceland
Fjaðrárgljúfur - (or: Fjaðrá Canyon, the Canyon where the Fjaðrá river runs through) is a rugged and impressive gorge, fairly wide, about 100 m deep and 2 km long. The gorge runs through hyoloclastite (soft granular rock) with lave layers and intrusions, the entire formation dating from the Ice age 2 million years ago.
Formation: When the ice cap retreated durin the last glacial period, a deep lake was formed in a valley above the present gorge, the water being retained behind a threshold of rock, with overflow water running down the slope now cut by the gorge. As rivers freed by the edge of the ice cap deposied a lot of sediment in the lake, the spill-water eroded the rock threshold and the hyaloclastite in from of it. The result was a powerful watercourse that cut the gorge we see today. Eventually it dwindled as the lake filled up and the river cut its way lower and lower into the sediment in the valley.
(Cited from an information sign at the location)
427