Clearwater Formation
Encyclopedia
The Clearwater Formation is a stratigraphical
unit of Albian
age
in the Western Canadian Sedimentary Basin
.
It takes the name from Clearweater River
. The formation is exposed on the banks of the Athabasca River
between Brule Falls and Boiler Falls, as well as along the Christina River, a tributary of the Clearwater River. It was first defined by R.G. McConnell in 1893.
and sandstone
interbeds. In the Cold Lake area it contains bituminous sands. The Wabiskaw Member consists of glauconitic
sandstone.
is produced from the Wabiskaw Member of the Clearwater Formation in the Wabasca Oil Field
. The formation contains bitumenous sand in the Cold Lake
and Primrose Lake
region.
as well as on the banks of the Christina River, south-east of Fort McMurray
. It reaches a maximum thickness of 85 metres (278.9 ft) on the Athabasca River, thins out to 6 metres (19.7 ft) in the Cold Lake
area, and wedges out towards the south. It is not present south of Edmonton.
. It is equivalent to the Bluesky Formation
and the lower Spirit River Formation
in the Peace River
region, may be equivalent to the Cummings Member in the Lloydminster
region, and corresponds to parts of the Manville Group in central Alberta
.
bed characterized by the presence of glauconite
. A thin fissile shale
bed occurs at its base, and separates it from the underlying McMurray Formation
.
It was defined in well Barnsdall West Wabiskaw No. 1 (located between Wabasca River
and Lesser Slave Lake
in central Alberta
) by P.C. Badgley in 1952. Heavy oil is extracted from the loose sandstone by means of horizontal drilling in the Wabasca Oil Field
.
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 Albian
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...
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 Clearweater River
Clearwater River (Saskatchewan)
Clearwater River is the name of a river in the Canadian provinces of Saskatchewan and Alberta.-Course:The Clearwater River totals 295 kilometres in length and rises in northwestern Saskatchewan in the northern forest region of the Precambrian Shield. From its headwaters at Broach Lake it flows...
. The formation is exposed on the banks 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...
between Brule Falls and Boiler Falls, as well as along the Christina River, a tributary of the Clearwater River. It was first defined by R.G. McConnell in 1893.
Lithology
The Clearwater Formation consists of black and green shaleShale
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 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,...
interbeds. In the Cold Lake area it contains bituminous sands. The Wabiskaw Member consists of 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.
Oil/gas production
Heavy OilPetroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
is produced from the Wabiskaw Member of the Clearwater Formation in the Wabasca Oil Field
Wabasca Oil Field
Wabasca is an oil field in a remote area of northern Alberta, where heavy petroleum is produced. It is also known as the Pelican Lake Oilfield.The closest community is Wabasca...
. The formation contains bitumenous sand in the Cold Lake
Cold Lake (Alberta)
Cold Lake is a large lake in Northern Alberta and Saskatchewan, Canada. The lake straddles the Alberta/Saskatchewan border, and has a water area of . It is also one of the deepest lakes in Alberta with a maximum depth of . It has around 24 known species of fish in it and is a major ice fishing lake...
and Primrose Lake
Primrose Lake
Primrose Lake is a large lake in Saskatchewan and Alberta, Canada. The lake straddles the Alberta/Saskatchewan border, with most of the water surface in Saskatchewan. It is close to the better known Cold Lake, Alberta....
region.
Distribution
The Clearwater Formation occurs in the sub-surface of north-eastern and central Alberta, and is exposed on lower course of the Athabasca RiverAthabasca River
The Athabasca River originates from the Columbia Glacier of the Columbia Icefield in Jasper National Park in Alberta, Canada...
as well as on the banks of the Christina River, south-east of Fort McMurray
Fort McMurray, Alberta
Fort McMurray is an urban service area in the Regional Municipality of Wood Buffalo in Alberta, Canada. It was previously incorporated as a city on September 1, 1980. It became an urban service area when it amalgamated with Improvement District No. 143 on April 1, 1995 to create the Municipality...
. It reaches a maximum thickness of 85 metres (278.9 ft) on the Athabasca River, thins out to 6 metres (19.7 ft) in the Cold Lake
Cold Lake, Alberta
Cold Lake is a city in northeastern Alberta, Canada, named after the lake it is situated near.-Geography:The city is situated in Alberta's "Lakeland" district, 300 km northeast of Edmonton, near the Alberta-Saskatchewan provincial border. The area surrounding the city is sparsely populated,...
area, and wedges out towards the south. It is not present south of Edmonton.
Relationship to other units
The Clearwater Formation is conformably overlain by the Grand Rapids Formation and conformably overlays the McMurray FormationMcMurray Formation
The McMurray Formation is a stratigraphical unit of Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from Fort McMurray, and was first described in the outcrop occurring on the banks of the Athabasca River by F.H...
. It is equivalent to the Bluesky Formation
Bluesky Formation
The Bluesky Formation is a stratigraphical unit of Lower Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the hamlet of Bluesky, and was first described in Shell's Bluesky No. 1 well by Badgley in 1952..-Lithology:...
and the lower Spirit River Formation
Spirit River Formation
The Spirit River Formation is a stratigraphical unit of middle Albian age in the Western Canadian Sedimentary Basin.It takes the name from the Spirit River, and was first described in Imperial Oil Spirit River No...
in the Peace River
Peace River, Alberta
Peace River is a town in northwestern Alberta, Canada, situated along the banks of the Peace River, at its confluence with the Smoky River, the Heart River and Pat's Creek. It is located northwest of Edmonton, and northeast of Grande Prairie, along Highway 2. The Peace River townsite is nearly ...
region, may be equivalent to the Cummings Member in the Lloydminster
Lloydminster
Lloydminster is a Canadian city which has the unusual geographic distinction of straddling the provincial border between Alberta and Saskatchewan...
region, and corresponds to parts of the Manville 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...
.
Wabiskaw Member
The Wabiskaw Member occurs at the base of the Clearwater Formation, and is a thin sandstoneSandstone
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,...
bed characterized by the presence of glauconite
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...
. A thin 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...
bed occurs at its base, and separates it from the underlying McMurray Formation
McMurray Formation
The McMurray Formation is a stratigraphical unit of Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from Fort McMurray, and was first described in the outcrop occurring on the banks of the Athabasca River by F.H...
.
It was defined in well Barnsdall West Wabiskaw No. 1 (located between Wabasca River
Wabasca River
Wabasca River is a river in northern Alberta, Canada. It is a major tributary of the Peace River.It has a total drainage area of .-Course:...
and Lesser Slave Lake
Lesser Slave Lake
Lesser Slave Lake is a lake located in central Alberta, Canada, northwest of Edmonton. It is the second largest lake entirely within Alberta boundaries , covering and measuring over long and at its widest point. Lesser Slave Lake averages in depth and is at its deepest...
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...
) by P.C. Badgley in 1952. Heavy oil is extracted from the loose sandstone by means of horizontal drilling in the Wabasca Oil Field
Wabasca Oil Field
Wabasca is an oil field in a remote area of northern Alberta, where heavy petroleum is produced. It is also known as the Pelican Lake Oilfield.The closest community is Wabasca...
.