Stretching for approximately 100 kilometers along the southern edge of Lake Athabasca, in the Canadian province of Saskatchewan, are some of the most northerly active sand dunes on Earth. Unlike most dunes, which are associated with dry and arid region, the Athabasca Sand Dunes are located in the middle of a wetland and a boreal forest, making it one of the most unique sand dunes and a geological oddity. The dunes are spread across more than 30,000 hectares, and due to their unusual ecosystem, they harbor an extraordinarily diverse biological life.
The Athabasca Sand Dunes were formed about 8,000 to 9,000 years ago at the end of the last glacial period. As the ice sheet melted, meltwater washed enormous quantities of sand, silt and sediment from local sandstone into Lake Athabasca, whose water level was much higher then than it currently is. Then the lake receded, exposing the large sand deposits on the shores. The wind then molded the sand into the formations seen today, and it continues to do so, shaping and reshaping the dunes and pushing it into the surrounding forest.
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The Athabasca Sand Dunes were formed about 8,000 to 9,000 years ago at the end of the last glacial period. As the ice sheet melted, meltwater washed enormous quantities of sand, silt and sediment from local sandstone into Lake Athabasca, whose water level was much higher then than it currently is. Then the lake receded, exposing the large sand deposits on the shores. The wind then molded the sand into the formations seen today, and it continues to do so, shaping and reshaping the dunes and pushing it into the surrounding forest.
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