Charlevoix crater
Encyclopedia
The Charlevoix crater is a large eroded meteorite
impact crater
in the Charlevoix
region of Quebec
, Canada
. Only part of the crater is exposed at the surface, the rest being covered by the Saint Lawrence River
. The original crater is estimated to have been 54 kilometres (33.6 mi) in diameter
and the age is estimated to be 342 ± 15 million years (Mississippian). The projectile was probably a stony asteroid, at least 2 kilometres (1.2 mi) in diameter, and weighing an estimated 15 billion tonne. The Mont des Éboulements
, situated in the exact centre of the crater, is interpreted as the central uplift, a consequence of elastic rebound. The crater is classified as a multi-ringed basin with a central uplift.
The impact origin of Charlevoix crater was first realized in 1965 after the discovery of many shatter cone
s in the area. Other evidence for impact includes planar deformation features
(PDFs) in quartz
and feldspar
grains.
In contrast to the surrounding craggy Laurentian Mountains
, the crater is relatively smooth and flat, which has facilitated human settlement. Today, 90% of the people of Charlevoix live within this crater.
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
impact crater
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
in the Charlevoix
Charlevoix
The Charlevoix region, located in Quebec, includes parts of the north shore of the Saint Lawrence River and the Laurentian Mountains region of the Canadian Shield...
region of Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. Only part of the crater is exposed at the surface, the rest being covered by the Saint Lawrence River
Saint Lawrence River
The Saint Lawrence is a large river flowing approximately from southwest to northeast in the middle latitudes of North America, connecting the Great Lakes with the Atlantic Ocean. It is the primary drainage conveyor of the Great Lakes Basin...
. The original crater is estimated to have been 54 kilometres (33.6 mi) in diameter
Diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle...
and the age is estimated to be 342 ± 15 million years (Mississippian). The projectile was probably a stony asteroid, at least 2 kilometres (1.2 mi) in diameter, and weighing an estimated 15 billion tonne. The Mont des Éboulements
Les Éboulements, Quebec
Les Éboulements is a municipality in the Capitale-Nationale region of Quebec, Canada.Its population centres include Les Éboulements , Éboulements-Est , Cap-aux-Oies, Sainte-Marie-de-Charlevoix, and Saint-Joseph-de-la-Rive Les Éboulements is a municipality in the Capitale-Nationale region of Quebec,...
, situated in the exact centre of the crater, is interpreted as the central uplift, a consequence of elastic rebound. The crater is classified as a multi-ringed basin with a central uplift.
The impact origin of Charlevoix crater was first realized in 1965 after the discovery of many shatter cone
Shatter cone
Shatter cones are rare geological features that are only known to form in the bedrock beneath meteorite impact craters or underground nuclear explosions...
s in the area. Other evidence for impact includes planar deformation features
Planar deformation features
Planar deformation features, or PDFs, are optically recognizable microscopic features in grains of silicate minerals , consisting of very narrow planes of glassy material arranged in parallel sets that have distinct orientations with respect to the grain's crystal structure.PDFs are only produced...
(PDFs) in quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
and feldspar
Feldspar
Feldspars are a group of rock-forming tectosilicate minerals which make up as much as 60% of the Earth's crust....
grains.
In contrast to the surrounding craggy Laurentian Mountains
Laurentian mountains
The Laurentian Mountains are a mountain range in southern Quebec, Canada, north of the St. Lawrence River and Ottawa River, rising to a highest point of 1166 metres at Mont Raoul Blanchard, north east of Quebec City in the Reserve Faunique des Laurentides. The Gatineau, L'Assomption, Lièvre,...
, the crater is relatively smooth and flat, which has facilitated human settlement. Today, 90% of the people of Charlevoix live within this crater.