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
Petitot River Petitot River Petitot is a river in northern Alberta and British Columbia, Canada. It is a tributary of the Liard River. Petitot River originates from Bistcho Lake in northwestern Alberta, and flows westwards along the northern borders of Alberta and British Columbia. It then passes in the Northwest Territories, where it discharges in the Liard River at the village of Fort Liard. From there, its waters are carried to the Arctic Ocean through the Mackenzie River. The river takes its name from Father Émile Petitot, one of the first European to reach the area in 1867–68. The name in the