Charlevoix impact structure

The Charlevoix impact structure is a large eroded meteorite impact structure in the Charlevoix region of Quebec, Canada.<ref name=EIDBCharlevoix>Template:Cite Earth Impact DB</ref> Only part of the impact structure is exposed at the surface, the rest lying beneath the Saint Lawrence River.

Description

The original impact structure is estimated to have been Template:Convert in diameter and the age of the impact is estimated to be 450 ± 20 million years (Ordovician to Silurian age).<ref name="SchmiederOthers2019a">Schmieder, M., Shaulis, B.J., Lapen, T.J., Buchner, E. and Kring, D.A., 2019. In situ U–Pb analysis of shocked zircon from the Charlevoix impact structure, Québec, Canada. Meteoritics & Planetary Science. 54(8) pp. 1808-1827.</ref> The projectile was probably a stony asteroid, at least Template:Convert in diameter, and weighing an estimated Template:Convert. The Mont des Éboulements, situated in the exact centre of the impact structure, is interpreted as the central uplift, a consequence of elastic rebound.<ref name="grandsjardins">Interpretation Centre, Parc national des Grands-Jardins, Charlevoix</ref> The impact structure is classified as a multi-ringed basin with a central uplift.

The impact origin of Charlevoix impact structure was first realized in 1965 after the discovery of many shatter cones 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 impact structure is relatively smooth and flat, which has facilitated human settlement. Today, 90% of the people of Charlevoix live within this impact structure.<ref name="grandsjardins"/>

External links

• Earth Impact Database
• Satellite image of the region (from Google Maps)
• Aerial Exploration of the Charlevoix Structure