Kakisa Formation
Encyclopedia
The Kakisa 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 Frasnian
Frasnian
The Frasnian is one of two faunal stages in the Late Devonian epoch. It lasted from 385.3 ± 2.6 million years ago to 374.5 ± 2.6 million years ago. It was preceded by the Givetian stage and followed by the Famennian stage...

 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 Kakisa River
Kakisa River
Kakisa River is a river in the Northwest Territories of Canada. It is a major tributary of the Mackenzie River.The river gives the name to the Kakisa Formation, a stratigraphical unit of the Western Canadian Sedimentary Basin.-Course:...

, a tributary of the Mackenzie River
Mackenzie River
The Mackenzie River is the largest river system in Canada. It flows through a vast, isolated region of forest and tundra entirely within the country's Northwest Territories, although its many tributaries reach into four other Canadian provinces and territories...

, and was first described in outcrop on the banks of the Trout River
Trout River (Northwest Territories)
Trout River is a river in the Northwest Territories of Canada. It is a major tributary of the Mackenzie River.The river gives the name to the Trout River Formation, a stratigraphical unit of the Western Canadian Sedimentary Basin.-Course:...

 by H.R. Belyea and D.J. McLaren in 1962.

Lithology

The Kakisa Formation is composed of silty
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...

 and dolomitic
Dolomite
Dolomite is a carbonate mineral composed of calcium magnesium carbonate CaMg2. The term is also used to describe the sedimentary carbonate rock dolostone....

 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....

.

Reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....

 builders such as coral
Coral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...

s and stromatoporoids can be identified in the formation. It is refoid in its northern extent, where its thickness is variable.

Distribution

The Kakisa Formation reaches a maximum thickness of 57 metres (187 ft). it occurs at the surface in outcrops along the Kakisa River
Kakisa River
Kakisa River is a river in the Northwest Territories of Canada. It is a major tributary of the Mackenzie River.The river gives the name to the Kakisa Formation, a stratigraphical unit of the Western Canadian Sedimentary Basin.-Course:...

 between Tathlina Lake
Tathlina Lake
Tathlina Lake is a large, shallow lake, located in the Northwest Territories, Canada. An outcropping of the Kakisa Formation occurs along the side of this lake....

 and Kakisa Lake
Kakisa Lake
Kakisa Lake is a large lake located in the Northwest Territories, Canada. It is fed by the Kakisa River, and near to the community of Kakisa. An outcropping of the Kakisa Formation occurs along the side of this lake.-See also:...

 and as an escarpment
Escarpment
An escarpment is a steep slope or long cliff that occurs from erosion or faulting and separates two relatively level areas of differing elevations.-Description and variants:...

 along the Mackenzie River
Mackenzie River
The Mackenzie River is the largest river system in Canada. It flows through a vast, isolated region of forest and tundra entirely within the country's Northwest Territories, although its many tributaries reach into four other Canadian provinces and territories...

. In the sub-surface, it can be found 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...

, where it is typically 30 metres (98.4 ft) thick, and thins out towards the Peace River Arch.

Relationship to other units

The Kakisa Formation is disconformably
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...

 overlain by the Trout River Formation
Trout River Formation
The Trout River Formation is a stratigraphical unit of Late Devonian age in the Western Canadian Sedimentary Basin.It takes the name from the Trout River, and was first described on the banks of the river, upstream from the Mackenzie River, by C.H...

 and conformably overlays the Redknife Formation
Redknife Formation
The Redknife Formation is a stratigraphical unit of Devonian age in the Western Canadian Sedimentary Basin.It takes the name from Redknife River, a tributary of the Mackenzie River, and was first described in the banks of the Trout River, north of Trout Lake, Northwest Territories, at Table Rock...

 (east) or the Fort Simpson Formation
Fort Simpson Formation
The Fort Simpson Formation is a stratigraphical unit of Devonian age in the Western Canadian Sedimentary Basin.It takes the name from the settlement of Fort Simpson, and was first described in well Briggs Turkey Lake No. 1 by A.E...

 (west).

It is equivalent to parts of the Winterburn Group
Winterburn Group
The Winterburn Group is a stratigraphical unit of Frasnian age in the Western Canadian Sedimentary Basin.It takes the name from Winterburn area located west of Edmonton, and was first described in well P.A. Pyrcz No...

 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...

. Towards the west, it becomes 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...

y and turns into the Fort Simpson Formation
Fort Simpson Formation
The Fort Simpson Formation is a stratigraphical unit of Devonian age in the Western Canadian Sedimentary Basin.It takes the name from the settlement of Fort Simpson, and was first described in well Briggs Turkey Lake No. 1 by A.E...

.
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