Smoky Group
Encyclopedia
The Smoky 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 Late Cretaceous 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 Smoky River
Smoky River
Smoky River is a river in western Alberta, Canada. It is a major tributary of the Peace River. The descriptive name refers to the presence of "smouldering beds of coal in the riverbank" noted by the Cree Indians....

, and was first described in outcrops along the banks of the Smoky River, Spirit River and Pouce Coupe River
Pouce Coupe River
Pouce Coupe is a river in Alberta and British Columbia, Canada. It is a major tributary of the Peace River.Originating in Alberta's Saddle Hills County, it flows into British Columbia's Peace River Regional District, then returns in Alberta in Clear Hills County, where it empties into the Peace...

s by George Mercer Dawson
George Mercer Dawson
Dr. George Mercer Dawson F.R.S., C.M.G., was a Canadian scientist and surveyor. He was born in Pictou, Nova Scotia, the eldest son of Sir John William Dawson, Principal of McGill University and his wife, Lady Margaret Dawson...

 in 1881..

Lithology

The Smoky Group is represented by marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 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...

 with ironstone
Ironstone
Ironstone is a sedimentary rock, either deposited directly as a ferruginous sediment or created by chemical repacement, that contains a substantial proportion of an iron compound from which iron either can be or once was smelted commercially. This term is customarily restricted to hard coarsely...

 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...

 streaks. 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,...

 occurs at the base, and is transitional to the Dunvegan Formation
Dunvegan Formation
The Dunvegan Formation is a stratigraphical unit of Cenomanian age in the Western Canadian Sedimentary Basin.It takes the name from the settlement of Dunvegan, Alberta, and was first described in an outcrop on Peace River near Dunvegan by George Mercer Dawson in 1881.-Lithology:The Dunvegan...

.

Hydrocarbon 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 the southern reaches of the Group, 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 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...

.

Distribution

The Kaskapau Shale reaches 477m in the Pouce Coupe River
Pouce Coupe River
Pouce Coupe is a river in Alberta and British Columbia, Canada. It is a major tributary of the Peace River.Originating in Alberta's Saddle Hills County, it flows into British Columbia's Peace River Regional District, then returns in Alberta in Clear Hills County, where it empties into the Peace...

 area and thins towards the east in the Smoky River
Smoky River
Smoky River is a river in western Alberta, Canada. It is a major tributary of the Peace River. The descriptive name refers to the presence of "smouldering beds of coal in the riverbank" noted by the Cree Indians....

 area. The Bad Heart Formation sandstone is up to 8m thick, while the Puskwaskau Formation ranges from 200m in the Pouce Coupe Prairie to 123m in the Spirit River
Spirit River, Alberta
Spirit River is a town in northern Alberta, Canada. It is located north of Grande Prairie at the junction of Highway 49 and Highway 731.The community is largely agricultural, being located in the fertile Peace Country. Together with neighboring Rycroft, it is a service centre for the oil and gas...

 area. The entire group measures up to 677 m (2,221.1 ft) in the Pouce Coupe Prairie, and can reach 1100 m (3,608.9 ft) 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 of northeast 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 Smoky Group is conformably and transgressively
Transgression (geology)
A marine transgression is a geologic event during which sea level rises relative to the land and the shoreline moves toward higher ground, resulting in flooding. Transgressions can be caused either by the land sinking or the ocean basins filling with water...

 followed by the Wapiti Group
Wapiti Group
The Wapiti Group is a stratigraphical unit of Cretaceous age in the Western Canadian Sedimentary Basin. It has formation status in Alberta and group status in British Columbia....

 and rests conformably on the Dunvegan Formation
Dunvegan Formation
The Dunvegan Formation is a stratigraphical unit of Cenomanian age in the Western Canadian Sedimentary Basin.It takes the name from the settlement of Dunvegan, Alberta, and was first described in an outcrop on Peace River near Dunvegan by George Mercer Dawson in 1881.-Lithology:The Dunvegan...

 sandstone. The 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:...

 sandstone and Muskiki
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...

 shale are replacing the upper parts of 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 the south-east of the distribution area. The entire group correlates with the Blackstone Formation, 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 Wapiabi Formation of the Alberta Group
Alberta Group
The Alberta Group is a stratigraphical unit of Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the province of Alberta, and was first described in outcrops along the Highwood River in southern Alberta by G.S. Hume in 1930....

 in the southern foothills. The equivalent stratigraphic sequence 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...

 consists of the 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...

 and 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...

, in north-eastern Alberta it correlates with Labiche Formation, and with the Kotaneelee Formation
Kotaneelee Formation
The Kotaneelee Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the Kotaneelee River, and was first described in outcrop in the river valley by C.O...

 in the Liard River
Liard River
The Liard River flows through Yukon, British Columbia and the Northwest Territories, Canada. Rising in the Saint Cyr Range of the Pelly Mountains in southeastern Yukon, it flows southeast through British Columbia, marking the northern end of the Rocky Mountains and then curving northeast back...

 area.

Subdivisions

The Smoky Group has the following sub-divisions 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
Puskwaskau Formation  Santonian
Santonian
The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous epoch or Upper Cretaceous series. It spans the time between 85.8 ± 0.7 mya and 83.5 ± 0.7 mya...

 
dark marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 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...

, 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...

 beds
200 m (656.2 ft)
Bad Heart Formation  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...

 
medium to coarse grained marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 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,...

 
8 m (26.2 ft)
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...

 
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...

 
dark, fissile 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...

 
900 m (2,952.8 ft)
Basal sandstone tongues
Howard Creek Member  late 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...

 
fine to medium grained glauconitic
Glauconite
Glauconite is an iron potassium phyllosilicate mineral of characteristic green color with very low weathering resistance and very friable.It crystallizes with a monoclinic geometry...

 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,...

 
4 m (13.1 ft)
Doe Creek Member  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...

 
fine grained 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,...

 
25 m (82 ft)
Pouce Coupe Member  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...

 
massive, fine grained 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,...

 
9 m (29.5 ft)

The Kaskapau Formation is equivalent to the sum of Blackstone Formation, 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 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...

.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK