The Alberta 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 Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 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 province of 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...

, and was first described in outcrops along 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 southern Alberta

Southern Alberta

Southern Alberta is a region located in the Canadian province of Alberta. As of the year 2004, the region's population was approximately 272,017. The primary cities are Lethbridge and Medicine Hat...

 by G.S. Hume in 1930.

Lithology

The Alberta Group is composed of silty 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...

 for the most part. Two thick 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...

 deposits (Blackstone Formation and Wapiabi Formation) are present above and below a 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,...

 sequence (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:...

). Sideritic

Siderite

Siderite is a mineral composed of iron carbonate FeCO3. It takes its name from the Greek word σίδηρος sideros, “iron”. It is a valuable iron mineral, since it is 48% iron and contains no sulfur or phosphorus...

 concretions and thin argillaceous 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....

 beds are present within the shale stacks.

Oil/gas production

Gas

Natural gas

Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...

 is produced from 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:...

 in Yellowhead County

Yellowhead County, Alberta

Yellowhead County is a municipal district in west central Alberta, Canada.It is the only county in Alberta Division 14, and shares the boundaries with this census division.-History:*1994: Established as a Municipal District of Yellowhead No...

.

Distribution

The Alberta Group occurs along 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 United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

-Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 border to the Athabasca River

Athabasca River

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

. In its type locality along 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 Southern Alberta

Southern Alberta

Southern Alberta is a region located in the Canadian province of Alberta. As of the year 2004, the region's population was approximately 272,017. The primary cities are Lethbridge and Medicine Hat...

, the group has a thickness of 610 feet (185.9 m). It reaches a maximum of 1219 feet (371.6 m) north of the North Saskatchewan River

North Saskatchewan River

The North Saskatchewan River is a glacier-fed river that flows east from the Canadian Rockies to central Saskatchewan. It is one of two major rivers that join to make up the Saskatchewan River....

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Relationship to other units

The Alberta Group is conformably overlain by the Belly River Formation and rests unconformably

Unconformity

An unconformity is a buried erosion surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval of time before deposition of the younger, but the term is used to describe...

 on deposits of the Blairmore Group and Luscar Group 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 and on the volcanic Crowsnest Formation

Crowsnest Formation

The Crowsnest Formation, also called the Crowsnest Volcanics, is a well-known outcroping of volcanic rock in southwestern Alberta, Canada. These volcanics were formed about 100 million years ago during the Cretaceous period and is estimated to cover a volume of...

 in southern Alberta

Southern Alberta

Southern Alberta is a region located in the Canadian province of Alberta. As of the year 2004, the region's population was approximately 272,017. The primary cities are Lethbridge and Medicine Hat...

's west. The group is equivalent with the Colorado Group

Colorado Group

The Colorado Group, also called the Colorado shale, is a stratigraphical unit of Cretaceous age in the Western Canadian Sedimentary Basin.It was first described in the Rocky Mountains front ranges of Colorado by A. Hague and S.E...

 and Lea Park Formation

Lea Park Formation

The Lea Park Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin, Canada.It takes the name from the settlement of Lea Park, Alberta, located north-west of Lloydminster on the banks of the North Saskatchewan River. It was first defined in an outcrop...

 in southern Alberta's prairies, and with 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...

 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...

 and north-east 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...

.

The Wapiabi Formation is equivalent to the upper Colorado Group

Colorado Group

The Colorado Group, also called the Colorado shale, is a stratigraphical unit of Cretaceous age in the Western Canadian Sedimentary Basin.It was first described in the Rocky Mountains front ranges of Colorado by A. Hague and S.E...

 shales and Lea Park Formation

Lea Park Formation

The Lea Park Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin, Canada.It takes the name from the settlement of Lea Park, Alberta, located north-west of Lloydminster on the banks of the North Saskatchewan River. It was first defined in an outcrop...

 in central Alberta

Central Alberta

Central Alberta is a region located in the Canadian province of Alberta.Central Alberta is the most densely populated rural area in the province...

 and the sum of Puskwaskau Formation, Bad Heart Formation and Muskiki Formation

Muskiki Formation

The Muskiki Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin.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...

 in the west part of 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...

.

Subdivisions

The Alberta Group has the following sub-divisions from top to base:

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
Wapiabi Formation	Campanian Campanian The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma ...	marine 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... , which sideritic Siderite Siderite is a mineral composed of iron carbonate FeCO3. It takes its name from the Greek word σίδηρος sideros, “iron”. It is a valuable iron mineral, since it is 48% iron and contains no sulfur or phosphorus...  concretions, 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... , 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 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....   *contains the Chungo Member sandstone	640 m (2,099.7 ft)
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:...	Turonian Turonian The Turonian is, in the ICS' geologic timescale, the second age in the Late Cretaceous epoch, or a stage in the Upper Cretaceous series. It spans the time between 93.5 ± 0.8 Ma and 89.3 ± 1 Ma...  to Coniacian Coniacian The Coniacian is an age or stage in the geologic timescale. It is a subdivision of the Late Cretaceous epoch or Upper Cretaceous series and spans the time between 89.3 ± 1 Ma and 85.8 ± 0.7 Ma...	marine 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,...	108 m (354.3 ft)
Blackstone Formation	Cenomanian Cenomanian The Cenomanian is, in the ICS' geological timescale the oldest or earliest age of the Late Cretaceous epoch or the lowest stage of the Upper Cretaceous series. An age is a unit of geochronology: it is a unit of time; the stage is a unit in the stratigraphic column deposited during the corresponding...  to Turonian Turonian The Turonian is, in the ICS' geologic timescale, the second age in the Late Cretaceous epoch, or a stage in the Upper Cretaceous series. It spans the time between 93.5 ± 0.8 Ma and 89.3 ± 1 Ma...	marine 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...  and 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...  with minor 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.... , 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 bentonite Bentonite Bentonite is an absorbent aluminium phyllosilicate, essentially impure clay consisting mostly of montmorillonite. There are different types of bentonite, each named after the respective dominant element, such as potassium , sodium , calcium , and aluminum . Experts debate a number of nomenclatorial... *contains the Jumping Pound Member sandstone	426 m (1,397.6 ft)