The Stoddart Group 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 Mississippian to Early Pennsylvanian 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 the Stoddart Creek, a creek that flows into Charlie Lake north of Fort St. John

Fort St. John, British Columbia

The City of Fort St. John is a city in northeastern British Columbia, Canada. A member municipality of the Peace River Regional District, the city covers an area of about 22 km² with 22,000 residents . Located at Mile 47, it is one of the largest cities along the Alaska Highway. Originally...

, and was first described in well Pacific Fort St. John #23 (at depths from 2000 to 2600m) by A.T.C. Rutgers in 1958.

Distribution

The Stoddart Group reaches a maximum thickness of 660 metres (2,165.4 ft) in the sub-surface north of Fort St. John

Fort St. John, British Columbia

The City of Fort St. John is a city in northeastern British Columbia, Canada. A member municipality of the Peace River Regional District, the city covers an area of about 22 km² with 22,000 residents . Located at Mile 47, it is one of the largest cities along the Alaska Highway. Originally...

 in 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...

. It is present in the sub-surface from the foothills of the Northern Rockies and eastwards into the Peace River Country

Peace River Country

The Peace River Country is an aspen parkland region around the Peace River in Canada. It spans from northwestern Alberta to the Rocky Mountains in northeastern British Columbia, where the region is also referred to as the Peace River Block.- Geography :The Peace River Country includes the...

 in north-western Alberta

Alberta

Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...

.

Subdivisions

The Stoddart Group is composed of the following formations, from top to bottom:

Sub-unit	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...	Lithology	Max. Thickness	Reference
Taylor Flat Formation	Early Pennsylvanian	limestone Limestone Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera.... , dolomite Dolomite Dolomite is a carbonate mineral composed of calcium magnesium carbonate CaMg2. The term is also used to describe the sedimentary carbonate rock dolostone.... , occasional 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,... , calcareous 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...	152 m (498.7 ft)
Kiskatinaw Formation Kiskatinaw Formation The Kiskatinaw Formation is a stratigraphical unit of Mississippian age in the Western Canadian Sedimentary Basin.It takes the name from the Kiskatinaw River, and was first described in the Pacific Fort St. John No. 23 well by H.L. Halbertsma in 1959...	Chesterian	quartzose 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,... , dark grey 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... , rare carbonate Carbonate In chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, . The name may also mean an ester of carbonic acid, an organic compound containing the carbonate group C2....	183 m (600.4 ft)
Golata Formation	late Meramecian-Chesterian	fossiliferous limestone Limestone Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera.... , shales Shalës Shalës is a municipality in the Elbasan District, Elbasan County, central Albania. The municipality consists of the villages Shalës, Licaj, Kurtalli, Xibrake, Xherie and Kodras.... , occasional siltstone Siltstone Siltstone is a sedimentary rock which has a grain size in the silt range, finer than sandstone and coarser than claystones.- Description :As its name implies, it is primarily composed of silt sized particles, defined as grains 1/16 - 1/256 mm or 4 to 8 on the Krumbein phi scale... , coal Coal Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...  and anhydrite Anhydrite Anhydrite is a mineral – anhydrous calcium sulfate, CaSO4. It is in the orthorhombic crystal system, with three directions of perfect cleavage parallel to the three planes of symmetry. It is not isomorphous with the orthorhombic barium and strontium sulfates, as might be expected from the...	50 m (164 ft)

Relationship to other units

The Stoddart Group is overlain by the Ishbel Group

Ishbel Group

The Ishbel Group is a stratigraphical unit of Permian age in the Western Canadian Sedimentary Basin.It was first defined by A. McGugan in 1963...

 in the foothills and the Prophet Formation in the northern plains; it conformably overlays the Debolt Formation

Debolt Formation

The Debolt Formation is a stratigraphical unit of Meramecian age in the Western Canadian Sedimentary Basin.It takes the name from the hamlet of Debolt, Alberta, and was first described in the Amerada Crown GF23-11 well near Debolt by G...

.

It can be correlated with the Tunnel Mountain Formation, the Kananaskis Formation, the Mattson Formation and the Mount Head Formation of the southern 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...

, and with the Amsden Formation in Montana

Montana

Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

.