Mackenzie River great depths to bedrock. A characteristic feature of the delta is its numerous pingos, or hills of earth-covered-ice – some 1,400 of them. The Peel River, carrying much of the runoff from the northern Yukon, joins in the delta at a point northeast of Fort McPherson. Below there, the Mackenzie diverges into several large channels with the largest heading north-northeast, emptying into the Beaufort Sea west of Tuktoyaktuk. At , the Mackenzie River drainage basin encompasses nearly 20 percent of Canada. About , or 54 percent of the basin, lies above Great Slave Lake. Permafrost underlies about three-quarters of the
Christina Lake (Alberta) River at its western end. The Jackfish River flows before it empties into the Christina River, a tributary of the Clearwater River. The waters eventually reach the Arctic Ocean via the Athabasca and MacKenzie Rivers. Christina Lake and the Christina River were named to honour Christine Gordon, originally from Scotland, who was the first white woman to live permanently in the Fort McMurray area, where she remained until her death in the 1940s. She was highly respected by the community, including the First Nations and Métis. Gordon, partly based on knowledge gleaned from a Scottish home nursing book, made her