The Lac Wiyâshâkimî (the official name, in French, formerly Lac à l'Eau Claire, a calque of the lake's name, Wiyâšâkamî, in Northern East Cree, changed form of wâšâkamî or wâšekamî in more southerly Cree dialects),[citation needed] also called the Clearwater Lakes in English and Allait Qasigialingat by the Inuit,[3][a] are a pair of annular lakes and impact structures on the Canadian Shield in Quebec, Canada, near Hudson Bay.

The lakes are actually a single body of water with a sprinkling of islands forming a "dotted line" between the eastern and western parts.

[2] In 1896, the explorer and geologist Albert Peter Low, a member of the Geological Survey of Canada, provided a probable explanation for the lakes' descriptive Cree name by highlighting the extraordinary clarity and depth of their icy waters.

[5][6] Both craters were previously believed to have the same age, 290 ± 20 million years (Permian period),[7] promoting the long-held idea that they formed simultaneously.

According to this doublet impact crater theory initially proposed by Michael R. Dence and colleagues in 1965,[8] the impactors may have been gravitationally bound as a binary asteroid, a suggestion also made by Thomas Wm.