Manicouagan Reservoir (also Lake Manicouagan) is an

annular lake An impact crater lake is a lake inside a depression caused by the impact of a meteor. It is also known as an annular lake in cases where the water body is shaped like a ring, as many impact crater lakes are. Examples One of the largest impac ...

in central

Quebec Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...

, Canada, covering an area of . The

lake island A lake island is any landmass within a lake. It is a type of inland island. Lake islands may form a lake archipelago. Formation Lake islands may form in numerous ways. They may occur through a build-up of sedimentation as shoals, and become ...

in its centre is known as

René-Levasseur Island René-Levasseur Island is a large island in the centre of Lake Manicouagan in Quebec, Canada. Its highest peak is Mount Babel, at 952 m (3,123 feet), which is contained in the Louis-Babel Ecological Reserve. With a total area of 2,020&n ...

, and its highest point is Mount Babel. The structure was created 214 (±1) million years ago, in the

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch ...

, by the impact of a meteorite in diameter. The lake and island are clearly seen from space and are sometimes called the "eye of Quebec". The lake has a volume of .

Geography

Manicouagan Reservoir in winter by Sentinel-2

The reservoir is located in

Manicouagan Regional County Municipality Manicouagan is a regional county municipality in the Côte-Nord region of Quebec, Canada. It is located on the north shore of the Saint Lawrence River with its seat in Baie-Comeau. It was created in 1981, and named after the Manicouagan River. Su ...

in the

Côte-Nord Côte-Nord (, ; ; land area ) is the second-largest administrative region by land area in Quebec, Canada, after Nord-du-Québec. It covers much of the northern shore of the Saint Lawrence River estuary and the Gulf of Saint Lawrence past Tadous ...

region of Quebec, Canada, about north of the city of

Baie-Comeau Baie-Comeau (; 2021 city population 20,687; CA population 26,643) is a city located approximately north-east of Quebec City in the Côte-Nord region of the province of Quebec, Canada. It is located on the shores of the Saint Lawrence River nea ...

, although its northernmost part is located in

Caniapiscau Regional County Municipality Caniapiscau is a regional county municipality in the Côte-Nord region of Quebec, Canada. The seat is Fermont. The census groups Caniapiscau RCM with neighbouring Sept-Rivières into the single census division of Sept-Rivières—Caniapiscau. ...

Quebec Route 389 Quebec's Route 389 connects Route 138 adjacent to Baie-Comeau with the Newfoundland and Labrador border, connecting with the Trans-Labrador Highway (Newfoundland and Labrador provincial route 500) to Wabush and Labrador City, and beyond to Goose ...

passes the eastern shore of the lake. The crater is a multiple-ring structure about across, with the reservoir at its diameter inner ring being its most prominent feature. It surrounds an inner island plateau called

and Mount Babel is the highest peak of the island, at above sea level and above the reservoir level. The Louis-Babel Ecological Reserve makes up the central part of the island.

Impact structure

Manicouagan Reservoir lies within the remnant of an ancient, deeply eroded

impact crater An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters ...

(

Impact structure An impact structure is a generally circular or craterlike geologic structure of deformed bedrock or sediment produced by impact on a planetary surface, whatever the stage of erosion of the structure. In contrast, an impact crater is the surface ...

). The crater was formed following the impact of an

asteroid An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. ...

with a diameter of , which excavated a crater originally about wide, although erosion and deposition of sediments have since reduced the visible diameter to about . It is the Earth's sixth-largest confirmed impact structure according to rim-to-rim diameter. Mount Babel is interpreted as the central peak of the crater, formed by post-impact

uplift Uplift may refer to: Science * Geologic uplift, a geological process ** Tectonic uplift, a geological process * Stellar uplift, the theoretical prospect of moving a stellar mass * Uplift mountains * Llano Uplift * Nemaha Uplift Business * Uplif ...

. 1992 radiometric dating has estimated that impact melt within the impact structure has an age of 214 ± 1 million years. A later estimate found an age of 215.4 ± 0.16 Ma. As this is more than 12 million years before the end of the Triassic, the impact that produced the crater cannot have been the cause of the

Triassic–Jurassic extinction event The Triassic–Jurassic (Tr-J) extinction event, often called the end-Triassic extinction, marks the boundary between the Triassic and Jurassic periods, , and is one of the top five major extinction events of the Phanerozoic eon, profoundly affect ...

Multiple impact event claims

It was suggested that the Manicouagan crater may have been part of a multiple

impact event An impact event is a collision between astronomical objects causing measurable effects. Impact events have physical consequences and have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or me ...

which also formed the

Rochechouart impact structure Rochechouart impact structure or Rochechouart astrobleme is an impact structure in France. Erosion has over the millions of years has mostly destroyed its impact crater, the initial surface expression of the asteroid impact leaving highly deform ...

in France, the

Saint Martin crater Saint Martin is an impact crater in Manitoba, Canada. It is located in the northern part of the Rural Municipality of Grahamdale, northwest of Lake St. Martin. The crater is in diameter and its age was determined to be 227.8 ± 1.1 million year ...

Manitoba Manitoba ( ) is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population o ...

, the

Obolon' crater Obolon' crater uk, Оболонь is a diameter buried meteorite impact crater situated about southeast of Kyiv in Ukraine (Poltava Oblast). The site has been drilled, which revealed the presence of shocked minerals and impact melt rock; the h ...

Ukraine Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...

, and the

Red Wing crater Red Wing or Red Wing Creek structure is a meteor crater located in McKenzie County, North Dakota, about southwest of Watford City, North Dakota, United States. The crater is not exposed to the surface, but was discovered using seismic techniqu ...

North Dakota North Dakota () is a U.S. state in the Upper Midwest, named after the Native Americans in the United States, indigenous Dakota people, Dakota Sioux. North Dakota is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north a ...

. David Rowley, a

geophysicist Geophysics () is a subject of natural science concerned with the physical processes and physical properties of the Earth and its surrounding space environment, and the use of quantitative methods for their analysis. The term ''geophysics'' som ...

, with the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...

, working with John Spray of the

University of New Brunswick The University of New Brunswick (UNB) is a public university with two primary campuses in Fredericton and Saint John, New Brunswick. It is the oldest English-language university in Canada, and among the oldest public universities in North Ameri ...

and Simon Kelley of the

Open University The Open University (OU) is a British public research university and the largest university in the United Kingdom by number of students. The majority of the OU's undergraduate students are based in the United Kingdom and principally study off- ...

, discovered that the five craters appeared to form a chain, indicating the breakup and subsequent impact of an asteroid or comet, similar to the well observed string of impacts of

Comet Shoemaker–Levy 9 Comet Shoemaker–Levy 9 ( formally designated D/1993 F2) broke apart in July 1992 and collided with Jupiter in July 1994, providing the first direct observation of an extraterrestrial collision of Solar System objects. This generated a ...

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...

in 1994. However, more recent work has found that the craters formed many millions of years apart, with the Saint Martin crater dating to 227.8 ± 1.1 Ma. While the Rochechouart structure formed 206.92 ± 0.20/0.32 Ma.

Hydroelectric project

The Manicouagan Reservoir as it presently exists was created in the 1960s, by flooding the earlier Lake Mushalagan (Mouchalagan) to the west of the central plateau and then-smaller Manicouagan to the east, by construction of the Daniel-Johnson dam. The works were part of the enormous Manicouagan or Manic series of

hydroelectric Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and ...

projects undertaken by Hydro-Québec, the provincial electrical utility. The complex of dams is also called the Manic-Outardes Project because the rivers involved are the Manicouagan and the Outardes. The reservoir acts as a giant headpond for the Manicouagan River, feeding the

Jean-Lesage generating station The Jean-Lesage generating station, (French: Centrale Jean-Lesage) formerly known as Manic-2, is a dam located 22 km from Baie-Comeau built on Manicouagan River in Quebec, Canada. It was constructed between 1961 and 1967. On June 22, 2010, t ...

(Manic-2), René-Lévesque generating station (Manic-3), and Daniel-Johnson Dam ( Manic-5) generating stations downstream. In the peak period of the winter cold, the lake surface is usually lower, since the

turbines A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful Work (physics), work. The work produced by a turbine can be used ...

run all the time at peak load to meet the huge electrical heating needs of the province. The surface of the lake also experiences low levels in the extreme periods of heat in

New England New England is a region comprising six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York to the west and by the Canadian provinces ...

during the summer, since in that period Hydro-Québec sells electrical energy to the joint New England grid and individual utilities in the United States.

References

External links