The geology of Alberta encompasses parts of the Canadian Rockies and thick sedimentary sequences, bearing coal, oil and natural gas, atop complex Precambrian crystalline basement rock.
The Precambrian granite and gneiss crystalline basement rocks beneath Alberta are extremely ancient, dating to the Archean and Proterozoic. The Slave Craton and Southern Alberta craton are the oldest units at more 2.5 billion years old, while younger units from the Proterozoic include the Wopmay orogeny, Great Slave Lake shear zone, Pre-Taltston basement, Taltson magmatic zone, Athabasca polymetamorphic terrane, Red Earth granulite domain, Kimiwan isotopic anomaly, Ksituan magmatic arc, Virgin River shear zone, Central Alberta intrusions and Lacombe domain. In many cases, Proterozoic deformation overprinted older Archean rocks. The Hudsonian Orogeny from 1.9 to 1.6 billion years ago was the last major regional metamorphic event. [1]
Throughout the late Precambrian and Paleozoic, a long-running marine transgression flooded western Alberta, accumulating sedimentary rocks on a basement of 1.8 billion year old Churchillian rocks.
Carbonate deposition common in the Paleozoic ended during the Jurassic as the North American continent moved westward with the opening of the Atlantic Ocean. The Guichon Batholith emplaced 200 million years ago, near Ashcroft, British Columbia and was accompanied by a period of erosion that wore away Devonian, Mississippian and Triassic strata from east to west. The Late Jurassic Morrison Formation, known for its stockpiles of dinosaur bones formed as uplift in the Black Hills of western South Dakota shed sediments into Alberta. Advancing river deltas lay down the Kootenay Formation and Ferni basin in the Banff area, with offshore sands forming the Nikanassin Formation in Jasper further north. Until the Valanginian, marine conditions continued in Peace River arch and Keg River low, forming the Cretaceous Bullhead and Minnes groups.
With the uplift of the Rocky Mountains, erosion accelerated in Alberta stripping away up to 3,500 feet (1,100 meters) of the Kootenay Formation. Rivers flowing across British Columbia reversed course with debris blockage and deposited the Elk conglomerate atop the Kootenay Formation. Rivers shifted northward toward the Arctic Ocean, which transgressed southward, flooding much of Alberta in the Aptian. Fluvial coal swamps and deltas of the Blairmore and Manville groups formed along the edge of the ocean. These shorelines were important for coal and oil and gas formation.
The Blairmore Group reaches up to 2,500 feet (760 meters) thick, divided into the Gladstone Formation conglomerate, sandstone, green shale and non-marine red shale, the Beaver Mines Formation with shale and chlorite sandstone and the Mill Creek Formation with pyroclastic flow sediments, related to Mesozoic volcanism in the Canadian Rockies.
North of the Calgary-Banff highway, the Gladstone and Beaver Mines Formation become carbonaceous and coal-bearing. A significant unconformity separates the Blairmore Group from overlying rocks.
During the Cenomanian and Albian, the connection with the Arctic Ocean was nearly severed, creating the Mowry sea, which developed its own endemic group of ammonites. Fossils across western Canada with both exotic and endemic fish scales and ammonites indicates that the Gulf of Mexico flooded the area from the south. The sea filled with fine sediments of the Colorado Group concurrent with the deposition of clastic and volcanic sediments in the Mill Creek Formation. The Joli Fou shale and Viking (Bow Island) sand, plus lower Colorado Group shales cover the Blaimore Group in southern Alberta.
The Colorado Group (known locally as the Alberta Group) occupies the Cordilleran foothills with the 1700-foot thick Blackstone Formation near Nordegg, which holds silty and platy shales, together with the Cardium Formation marine sandstone and shales, and the Wapiabi Formation which reaches up to 2000 feet thick with mudstone, ironstone and ammonite fossils. [2]
During the Cenozoic sedimentation continued in the Western Canada Sedimentary Basin, spanning Alberta. The Paskapoo Formation deposited near the Rockies, together with the Ravenscrag Formation in the southern Cypress Hills Formation. The Paskapoo Formation reaches up to one kilometre thick and holds fossils of gliding mammals and early pangolins. [3]
The geology of India is diverse. Different regions of India contain rocks belonging to different geologic periods, dating as far back as the Eoarchean Era. Some of the rocks are very deformed and altered. Other deposits include recently deposited alluvium that has yet to undergo diagenesis. Mineral deposits of great variety are found in the Indian subcontinent in huge quantities. Even India's fossil record is impressive in which stromatolites, invertebrates, vertebrates and plant fossils are included. India's geographical land area can be classified into the Deccan Traps, Gondwana and Vindhyan.
The Fernie Formation is a stratigraphic unit of Jurassic age. It is present in the western part of the Western Canada Sedimentary Basin in western Alberta and northeastern British Columbia. It takes its name from the town of Fernie, British Columbia, and was first defined by W.W. Leach in 1914.
The geology of Uruguay combines areas of Precambrian-aged shield units with a region of volcanic rock erupted during the Cretaceous and copious sedimentary facies the oldest of which date from the Devonian. Big events that have shaped the geology of Uruguay include the Transamazonian orogeny, the breakup of Rodinia and the opening of the South Atlantic.
The geology of Mozambique is primarily extremely old Precambrian metamorphic and igneous crystalline basement rock, formed in the Archean and Proterozoic, in some cases more than two billion years ago. Mozambique contains greenstone belts and spans the Zimbabwe Craton, a section of ancient stable crust. The region was impacted by major tectonic events, such as the mountain building Irumide orogeny, Pan-African orogeny and the Snowball Earth glaciation. Large basins that formed in the last half-billion years have filled with extensive continental and marine sedimentary rocks, including rocks of the extensive Karoo Supergroup which exist across Southern Africa. In some cases these units are capped by volcanic rocks. As a result of its complex and ancient geology, Mozambique has deposits of iron, coal, gold, mineral sands, bauxite, copper and other natural resources.
The geology of Tanzania began to form in the Precambrian, in the Archean and Proterozoic eons, in some cases more than 2.5 billion years ago. Igneous and metamorphic crystalline basement rock forms the Archean Tanzania Craton, which is surrounded by the Proterozoic Ubendian belt, Mozambique Belt and Karagwe-Ankole Belt. The region experienced downwarping of the crust during the Paleozoic and Mesozoic, as the massive Karoo Supergroup deposited. Within the past 100 million years, Tanzania has experienced marine sedimentary rock deposition along the coast and rift formation inland, which has produced large rift lakes. Tanzania has extensive, but poorly explored and exploited natural resources, including coal, gold, diamonds, graphite and clays.
The geological history of Zambia begins in the Proterozoic eon of the Precambrian. The igneous and metamorphic basement rocks tend to be highly metamorphosed and may have formed earlier in the Archean, but heat and pressure has destroyed evidence of earlier conditions. Major sedimentary and metamorphic groups formed in the mid-Proterozoic, followed by a series of glaciations in the Neoproterozoic and much of the Paleozoic which deposited glacial conglomerate as well as other sediments to form the Katanga Supergroup and rift-related Karoo Supergroup. Basalt eruptions blanketed the Karoo Supergroup in the Mesozoic and Zambia shifted to coal and sandstone formation. Geologically recent windblown sands from the Kalahari Desert and alluvial deposits near rivers play an important role in the modern surficial geology of Zambia. The country has extensive natural resources, particularly copper, but also cobalt, emeralds, other gemstones, uranium and coal.
The geology of Eswatini formed beginning 3.6 billion years ago, in the Archean Eon of the Precambrian. Eswatini is the only country entirely underlain by the Kaapvaal Craton, one of the oldest pieces of stable continental crust and the only craton regarded as "pristine" by geologists, other than the Yilgarn Craton in Australia. As such, the country has very ancient granite, gneiss and in some cases sedimentary rocks from the Archean into the Proterozoic, overlain by sedimentary rocks and igneous rocks formed during the last 539 million years of the Phanerozoic as part of the Karoo Supergroup. Intensive weathering has created thick zones of saprolite and heavily weathered soils.
The geology of Nigeria formed beginning in the Archean and Proterozoic eons of the Precambrian. The country forms the Nigerian Province and more than half of its surface is igneous and metamorphic crystalline basement rock from the Precambrian. Between 2.9 billion and 500 million years ago, Nigeria was affected by three major orogeny mountain-building events and related igneous intrusions. Following the Pan-African orogeny, in the Cambrian at the time that multi-cellular life proliferated, Nigeria began to experience regional sedimentation and witnessed new igneous intrusions. By the Cretaceous period of the late Mesozoic, massive sedimentation was underway in different basins, due to a large marine transgression. By the Eocene, in the Cenozoic, the region returned to terrestrial conditions.
The geology of South Dakota began to form more than 2.5 billion years ago in the Archean eon of the Precambrian. Igneous crystalline basement rock continued to emplace through the Proterozoic, interspersed with sediments and volcanic materials. Large limestone and shale deposits formed during the Paleozoic, during prevalent shallow marine conditions, followed by red beds during terrestrial conditions in the Triassic. The Western Interior Seaway flooded the region, creating vast shale, chalk and coal beds in the Cretaceous as the Laramide orogeny began to form the Rocky Mountains. The Black Hills were uplifted in the early Cenozoic, followed by long-running periods of erosion, sediment deposition and volcanic ash fall, forming the Badlands and storing marine and mammal fossils. Much of the state's landscape was reworked during several phases of glaciation in the Pleistocene. South Dakota has extensive mineral resources in the Black Hills and some oil and gas extraction in the Williston Basin. The Homestake Mine, active until 2002, was a major gold mine that reached up to 8000 feet underground and is now used for dark matter and neutrino research.
The geology of Wyoming includes some of the oldest Archean rocks in North America, overlain by thick marine and terrestrial sediments formed during the Paleozoic, Mesozoic and Cenozoic, including oil, gas and coal deposits. Throughout its geologic history, Wyoming has been uplifted several times during the formation of the Rocky Mountains, which produced complicated faulting that traps hydrocarbons.
The geology of Utah, in the western United States, includes rocks formed at the edge of the proto-North American continent during the Precambrian. A shallow marine sedimentary environment covered the region for much of the Paleozoic and Mesozoic, followed by dryland conditions, volcanism, and the formation of the basin and range terrain in the Cenozoic.
The bedrock of Colorado was assembled from island arcs accreted onto the edge of the ancient Wyoming Craton. The Sonoma orogeny uplifted the ancestral Rocky Mountains in parallel with the diversification of multicellular life. Shallow seas covered the regions, followed by the uplift current Rocky Mountains and intense volcanic activity. Colorado has thick sedimentary sequences with oil, gas and coal deposits, as well as base metals and other minerals.
The geology of Montana includes thick sequences of Paleozoic, Mesozoic and Cenozoic sedimentary rocks overlying ancient Archean and Proterozoic crystalline basement rock. Eastern Montana has considerable oil and gas resources, while the uplifted Rocky Mountains in the west, which resulted from the Laramide orogeny and other tectonic events have locations with metal ore.
The geology of Kazakhstan includes extensive basement rocks from the Precambrian and widespread Paleozoic rocks, as well as sediments formed in rift basins during the Mesozoic.
The geology of Kyrgyzstan began to form during the Proterozoic. The country has experienced long-running uplift events, forming the Tian Shan mountains and large, sediment filled basins.
The geology of North Korea has been studied by the Central Geological Survey of Mineral Resources, rare international research and by inference from South Korea's geology.
The geology of Bulgaria consists of two major structural features. The Rhodope Massif in southern Bulgaria is made up of Archean, Proterozoic and Cambrian rocks and is a sub-province of the Thracian-Anatolian polymetallic province. It has dropped down, faulted basins filled with Cenozoic sediments and volcanic rocks. The Moesian Platform to the north extends into Romania and has Paleozoic rocks covered by rocks from the Mesozoic, typically buried by thick Danube River valley Quaternary sediments. In places, the Moesian Platform has small oil and gas fields. Bulgaria is a country in southeastern Europe. It is bordered by Romania to the north, Serbia and North Macedonia to the west, Greece and Turkey to the south, and the Black Sea to the east.
Geology of Latvia includes an ancient Archean and Proterozoic crystalline basement overlain with Neoproterozoic volcanic rocks and numerous sedimentary rock sequences from the Paleozoic, some from the Mesozoic and many from the recent Quaternary past. Latvia is a country in the Baltic region of Northern Europe.
The geology of the Northwest Territories has been mapped in different quadrangles by the Canadian government. The region has some of the oldest rocks in the world and among the oldest in North America, formed from several sections of stable craton continental crust, including the Slave Craton, Rae Craton and Hearne Craton. These rocks form the Archean and Proterozoic Precambrian basement rock of the region and are the subject of extensive research to understand continental crust and tectonic conditions on the early Earth.
The Parnaíba Basin is a large cratonic sedimentary basin located in the North and Northeast portion of Brazil. About 50% of its areal distribution occurs in the state of Maranhão, and the other 50% occurring in the state of Pará, Piauí, Tocantins, and Ceará. It is one of the largest Paleozoic basins in the South American Platform. The basin has a roughly ellipsoidal shape, occupies over 600,000 km2, and is composed of ~3.4 km of mainly Paleozoic sedimentary rock that overlies localized rifts.