|
Hasler Formation
The Fort St. John Group is a stratigraphic unit of Lower Cretaceous age in the Western Canada Sedimentary Basin. It takes the name from the city of Fort St. John, British Columbia and was first defined by George Mercer Dawson in 1881. Lithology The Fort St. John Group is mostly composed of dark shale deposited in a marine environment. Bentonite is present in the shale, and it is interbedded with sandstone, siltstone and conglomerates. Distribution The Fort St. John Group occurs in the subsurface in the Peace River Country of northeastern British Columbia and north-western Alberta, in southern Yukon and southern Northwest Territories. It has a thickness of to . Relationship to other units The Fort St. John Group is conformably overlain by the Dunvegan Formation and conformably underlain by the Bullhead Group or may rest disconformably on older units. Subdivisions The Fort St. John Group is subdivided into the following formations: Canadian Rockies foothills of British Colu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness (geology), thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Canadian Sedimentary Basin
The Western Canada Sedimentary Basin (WCSB) underlies of Western Canada including southwestern Manitoba, southern Saskatchewan, Alberta, northeastern British Columbia and the southwest corner of the Northwest Territories. This vast sedimentary basin consists of a massive wedge of sedimentary rock extending from the Rocky Mountains in the west to the Canadian Shield in the east. This wedge is about thick under the Rocky Mountains, but thins to zero at its eastern margins. The WCSB contains one of the world's largest reserves of petroleum and natural gas and supplies much of the North American market, producing more than per day of gas in 2000. It also has huge reserves of coal. Of the provinces and territories within the WCSB, Alberta has most of the oil and gas reserves and almost all of the oil sands. Conventional oil The WCSB is considered a mature area for exploration of petroleum and recent development has tended toward natural gas and oil sands rather than conventio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albian
The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/series (stratigraphy), Series. Its approximate time range is 113.0 ± 1.0 annum, Ma to 100.5 ± 0.9 Ma (million years ago). The Albian is preceded by the Aptian and followed by the Cenomanian. Stratigraphic definitions The Albian Stage was first proposed in 1842 by Alcide d'Orbigny. It was named after Alba, the Latin name for Aube (river), River Aube in France. A Global Boundary Stratotype Section and Point (GSSP), ratified by the IUGS in 2016, defines the base of the Albian as the first occurrence of the planktonic foraminiferan ''Hedbergellidae, Microhedbergella renilaevis'' at the Col de Pré-Guittard section, Arnayon, Drôme, France. The top of the Albian Stage (the base of the Cenomanian Stage and Upper Cretaceous Series) is defined ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Unit
A stratigraphic unit is a volume of rock of identifiable origin and relative age range that is defined by the distinctive and dominant, easily mapped and recognizable petrographic, lithologic or paleontologic features ( facies) that characterize it. Units must be ''mappable'' and ''distinct'' from one another, but the contact need not be particularly distinct. For instance, a unit may be defined by terms such as "when the sandstone component exceeds 75%". Lithostratigraphic units Sequences of sedimentary and volcanic rocks are subdivided on the basis of their shared or associated lithology. Formally identified lithostratigraphic units are structured in a hierarchy of lithostratigraphic rank, higher rank units generally comprising two or more units of lower rank. Going from smaller to larger in rank, the main lithostratigraphic ranks are bed, member, formation, group and supergroup. Formal names of lithostratigraphic units are assigned by geological surveys. Units of forma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian Rockies
The Canadian Rockies () or Canadian Rocky Mountains, comprising both the Alberta Rockies and the British Columbian Rockies, is the Canadian segment of the North American Rocky Mountains. It is the easternmost part of the Canadian Cordillera, which is the northern segment of the North American Cordillera, the expansive system of interconnected mountain ranges between the Interior Plains and the Pacific Coast that runs northwest–southeast from central Alaska to the Isthmus of Tehuantepec in Mexico. Canada officially defines the Rocky Mountains system as the mountain chains east of the Rocky Mountain Trench extending from the Liard River valley in northern British Columbia to the Albuquerque Basin in New Mexico, not including the Mackenzie, Richardson and British Mountains/ Brooks Range in Yukon and Alaska (which are all included as the "Arctic Rockies" in the United States' definition of the Rocky Mountains system). The Canadian Rockies, being the northern segment of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unconformity
An unconformity is a buried erosional or non-depositional 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 layer, but the term is used to describe any break in the sedimentary geologic record. The significance of angular unconformity (see below) was shown by James Hutton, who found examples of Hutton's Unconformity at Jedburgh in 1787 and at Siccar Point in Berwickshire in 1788, both in Scotland. The rocks above an unconformity are younger than the rocks beneath (unless the sequence has been overturned). An unconformity represents time during which no sediments were preserved in a region or were subsequently eroded before the next deposition. The local record for that time interval is missing and geologists must use other clues to discover that part of the geologic history of that area. The interval ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northwest Territories
The Northwest Territories is a federal Provinces and territories of Canada, territory of Canada. At a land area of approximately and a 2021 census population of 41,070, it is the second-largest and the most populous of Provinces and territories of Canada#Territories, the three territories in Northern Canada. Its estimated population as of the first quarter of 2025 is 45,074. Yellowknife is the capital, most populous community, and the only city in the territory; its population was 20,340 as of the 2021 census. It became the territorial capital in 1967, following recommendations by the Carrothers Commission. The Northwest Territories, a portion of the old North-Western Territory, entered the Canadian Confederation on July 15, 1870. At first, it was named the North-West Territories. The name was changed to the present Northwest Territories in 1906. Since 1870, the territory has been divided four times to create new provinces and territories or enlarge existing ones. Its current ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yukon
Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s westernmost territory and the smallest territory by land area. As of the 2021 Canadian census, 2021 census, Yukon is the middle territory in terms of population, but the most densely populated. Yukon has an estimated population of 47,126 as of 2025. Whitehorse, the territorial capital, is the largest settlement. Yukon was History of the Northwest Territories, split from the Northwest Territories by a federal statute in 1898 as the Yukon Territory. The current governing legislation is a new statute passed by the federal Parliament in 2002, the ''Yukon Act''. That act established Yukon as the territory's official name, although Yukon Territory remains in popular usage. Canada Post uses the territory's internationally approved postal abbrevia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alberta
Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, the Northwest Territories to its north, and the U.S. state of Montana to its south. Alberta and Saskatchewan are the only two landlocked Canadian provinces. The eastern part of the province is occupied by the Great Plains, while the western part borders the Rocky Mountains. The province has a predominantly humid continental climate, continental climate, but seasonal temperatures tend to swing rapidly because it is so arid. Those swings are less pronounced in western Alberta because of its occasional Chinook winds. Alberta is the fourth largest province by area, at , and the fourth most populous, with 4,262,635 residents. Alberta's capital is Edmonton; its largest city is Calgary. The two cities are Alberta's largest Census geographic units ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peace River Country
The Peace River Country (or Peace Country; ) is an aspen parkland region centring on the Peace River in Canada. It extends from northwestern Alberta to the Rocky Mountains in northeastern British Columbia, where a certain portion of the region is also referred to as the Peace River Block. Geography The Peace River Country includes the incorporated communities of Fort St. John, Dawson Creek, Tumbler Ridge and Chetwynd in British Columbia. Major communities in the Alberta portion of the Peace Country include Grande Prairie, Peace River, High Level and Fairview. It has no fixed boundaries but covers some 260,000 to 390,000 km2 (100,000 to 150,000 square miles). In British Columbia, the area extends from Monkman Provincial Park and Tumbler Ridge in the south, to Hudson's Hope and the Williston Lake in the west, to Fort St. John and Charlie Lake in the north. The term is used also in a broader sense to mean the whole of the Northeastern Interior past the Rockies, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar, because they are the most resistant minerals to the weathering processes at the Earth's surface. Like uncemented sand, sandstone may be imparted any color by impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other topography, topographic features, certain colors of sandstone have become strongly identified with certain regions, such as the red rock deserts of Arches National Park and other areas of the Southwestern United States, American Southwest. Rock formations composed of sandstone usually allow the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bentonite
Bentonite ( ) is an Absorption (chemistry), absorbent swelling clay consisting mostly of montmorillonite (a type of smectite) which can either be Na-montmorillonite or Ca-montmorillonite. Na-montmorillonite has a considerably greater swelling capacity than Ca-montmorillonite. Bentonite usually forms from the weathering of volcanic ash in seawater, or by hydrothermal circulation through the porosity of volcanic ash beds, which converts (devitrification) the volcanic glass (obsidian, rhyolite, dacite) present in the ash into clay minerals. In the mineral alteration process, a large fraction (up to 40–50 wt.%) of amorphous silica is dissolution (chemistry), dissolved and leaching (agriculture), leached away, leaving the bentonite deposit in place. Bentonite beds are white or pale blue or green (traces of redox, reduced ) in fresh exposures, turning to a cream color and then yellow, red, or brown (traces of oxidation, oxidized ) as the exposure is weathered further. As a swel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
