The Trout River 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 Late Devonian 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...

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It takes the name from 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:...

, and was first described on the banks of the river, 35 kilometres (21.7 mi) upstream from 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...

, by C.H. Crickmay in 1953.

Lithology

The Trout River Formation is composed bedded 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....

 (top), silty limestone and 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...

 (middle), silty limestone and calcareous 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...

 (base).
Brachiopod

Brachiopod

Brachiopods are a phylum of marine animals that have hard "valves" on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection...

 and 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...

 paleo-fauna can be found in outcrops.

Distribution

The Trout River Formation reaches a maximum thickness of 91 metres (298.6 ft). It occurs in the District of Mackenzie

District of Mackenzie

The District of Mackenzie was a regional administrative district of Canada's Northwest Territories. The district consisted of the portion of the Northwest Territories directly north of British Columbia, Alberta, and Saskatchewan on Canada's mainland....

 in outcrop and dips south into the Fort Nelson

Fort Nelson, British Columbia

Fort Nelson is a town of approximately 5000 residents in British Columbia's northeastern corner. It is the administrative centre of the newly formed Northern Rockies Regional Municipality, a first for BC. The majority of Fort Nelson's economic activities have historically been concentrated in the...

 area 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...

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Relationship to other units

The Trout River Formation is conformably overlain by the Tetcho Formation

Tetcho Formation

The Tetcho Formation is a stratigraphical unit of Famennian age in the Western Canadian Sedimentary Basin.It takes the name from Tetcho Lake, and was first described in the Imperial Island River No. 1 well The Tetcho Formation is a stratigraphical unit of Famennian age in the Western Canadian...

 and 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...

 overlays the Kakisa Formation

Kakisa Formation

The Kakisa Formation is a stratigraphical unit of Frasnian age in the Western Canadian Sedimentary Basin.It takes the name from the Kakisa River, a tributary of the Mackenzie River, and was first described in outcrop on the banks of the Trout River by H.R. Belyea and D.J...

. In its western extent, it overlies and grades 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...

.

It is equivalent to the Sassenach Formation in the central Alberta Rockies, with the Graminia Formation 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...

, the Crowfoot Formation

Crowfoot Formation

The Crowfoot Formation is a stratigraphical unit of Frasnian age in the Western Canadian Sedimentary Basin.It takes the name from Crowfoot Creek, a tributary of the Bow River and was first described in the Royalite Crowfoot No. 2 well, located near the creek by H.R. Belyea and D.J. McLaren in 1957...

 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 Torquay Formation in Saskatchewan

Saskatchewan

Saskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota....

 and Lyleton Formation in Manitoba

Manitoba

Manitoba is a Canadian prairie province with an area of . The province has over 110,000 lakes and has a largely continental climate because of its flat topography. Agriculture, mostly concentrated in the fertile southern and western parts of the province, is vital to the province's economy; other...

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