2.1.11. Hautrage Flints Formation - HTR

Authors: Robaszynski (1975c).

Description: Chalky marls or coarse-grained chalks, slightly glauconitic, with numerous and voluminous irregular brown-black flints. These flints often contain numerous, small (mm size), white sponge spicules.

Stratotype: In the railway cutting at Hautrage (see Robaszynski, 1975, p. 36) .

Area: MonsBasin. Towards the west in France the equivalent is the  "Craie à cornus". Near the northern border of the Mons basin between Ghlin and Saint-Denis the Hautrage Formation is strongly silicified: see Saint-Denis Silicite Formation.

Thickness:  3 to 25 m near Saint-Vaast in the eastern part of the basin.

Age: Late Turonian on the basis of Micraster leskei.

Remarks: - These are the "Rabots" auct. (J. Cornet, 1923).

- The denomination "Formation d'Esplechin" (Doremus, 1997) is a junior synonym of the "Formation des Silex d'Hautrage" of  Robaszynski  (1975c).