The McMurray Formation is a stratigraphic unit of Early Cretaceous age (late Barremian to Aptian stage) of the Western Canada Sedimentary Basin in northeastern Alberta.

[3] It is a well-studied example of fluvial to estuarine sedimentation, and it is economically important because it hosts most of the vast bitumen resources of the Athabasca Oil Sands region.

The McMurray Formation consists of fine- to coarse-grained quartzitic sand and sandstone, interbedded with lesser amounts of silt, mud, clay and, less commonly, thin coal beds.

The depression was created by the dissolution of thick salt deposits in the Devonian Elk Point Group deep within the subsurface.

They are flanked by off-channel deposits that consist primarily of mud and silt that accumulated in the floodplain, tidal flat, swamp, and brackish-bay environments that existed contemporaneously with the channels.

[8] Ichnofossils such as Skolithos and Teichichnus that were created by burrowing organisms are common in the middle to upper portions of the McMurray Formation.

[13][15] Bitumen has been produced from the McMurray Formation in the Athabasca Oil Sands since 1967, at first by open-pit mining, and later from the subsurface as well, using in-situ techniques such as Steam-Assisted Gravity Drainage (SAGD).

As of 2010, the output of oil sands production had reached more than 1.6 million barrels per day (250,000 m3/d); 53% of this was produced by surface mining and 47% by in-situ methods.