The Muskiki Formation is a stratigraphical

Stratigraphy

Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....

 unit of Late Cretaceous

Late Cretaceous

The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...

 age

Geochronology

Geochronology is the science of determining the age of rocks, fossils, and sediments, within a certain degree of uncertainty inherent to the method used. A variety of dating methods are used by geologists to achieve this, and schemes of classification and terminology have been proposed...

 in the Western Canadian Sedimentary Basin

Western Canadian Sedimentary Basin

The Western Canadian Sedimentary Basin is a vast sedimentary basin underlying of Western Canada including southwestern Manitoba, southern Saskatchewan, Alberta, northeastern British Columbia and the southwest corner of the Northwest Territories. It consists of a massive wedge of sedimentary rock...

.

It takes the name from Muskiki Lake and Muskiki Creek, a tributary of the Cardinal River, and was first described in an outcrop along the Thistle Creek, north of Muskiki Lake, in the Bighorn Range, by D.F. Stott in 1963.

Lithology

The Muskiki Formationis composed of shale

Shale

Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...

 with pebbly mudstone

Mudstone

Mudstone is a fine grained sedimentary rock whose original constituents were clays or muds. Grain size is up to 0.0625 mm with individual grains too small to be distinguished without a microscope. With increased pressure over time the platey clay minerals may become aligned, with the...

. Poorly sorted sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

 and concretionary beds also occur. In the western areal it becomes more silt

Silt

Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. Silt may occur as a soil or as suspended sediment in a surface water body...

y.

Distribution

The Muskiki Formation is 99 metres (324.8 ft) thick at its type locality at Thistle Creek. It thins out towards the south and east. It occurs in the Canadian Rockies

Canadian Rockies

The Canadian Rockies comprise the Canadian segment of the North American Rocky Mountains range. They are the eastern part of the Canadian Cordillera, extending from the Interior Plains of Alberta to the Rocky Mountain Trench of British Columbia. The southern end borders Idaho and Montana of the USA...

 foothills from the Highwood River

Highwood River

The Highwood River is a river located in southwestern Alberta, Canada. It is part of the Bow River watershed. The river is known for its flyfishing. A variety of trout species live in the river, including native bull trout.-Course:...

 in the south to the Berland River, north of the Athabasca River

Athabasca River

The Athabasca River originates from the Columbia Glacier of the Columbia Icefield in Jasper National Park in Alberta, Canada...

 and into north-eastern British Columbia

British Columbia

British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...

.

Relationship to other units

The Muskiki Formationis is part of the Smoky Group

Smoky Group

The Smoky Group is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the Smoky River, and was first described in outcrops along the banks of the Smoky River, Spirit River and Pouce Coupe Rivers by George Mercer Dawson in...

. It is conformably underlain by the Cardium Formation

Cardium Formation

The Cardium Formation is a stratigraphical unit of Upper Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the Cockle shells, and was first described along the Bow River banks by James Hector in 1895.-Lithology:...

 and conformably overlain by the Bad Heart Formation.

The Kaskapau Formation

Kaskapau Formation

The Kaskapau Formation is a geological formation in North America whose strata date back to the Late Cretaceous.The name derives from kaskapahtew , the Cree word for "smoky".. It was first described on the banks of the Smoky River, close to the confluence with the Puskwaskau River by F.H...

 in northern Alberta

Northern Alberta

Northern Alberta is a region located in the Canadian province of Alberta.Its primary industry is oil and gas, with large heavy oil reserves being exploited at the Athabasca Oil Sands and Wabasca Area in the east of the region...

 replaces the upper Blackstone Formation, the Cardium Formation

Cardium Formation

The Cardium Formation is a stratigraphical unit of Upper Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the Cockle shells, and was first described along the Bow River banks by James Hector in 1895.-Lithology:...

, and the Muskiki Formation. Where the Kaskapau Formation includes post Cardium

Cardium Formation

The Cardium Formation is a stratigraphical unit of Upper Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the Cockle shells, and was first described along the Bow River banks by James Hector in 1895.-Lithology:...

 beds, the Muskiki is considered a member of the Wapiabi Formation.