2.1.2.HaineGreen Sandstone Group - HNE

Authors: Robaszynski, herein.

Description:Detriticfacies, more or less conglomeratic and glauconitic, with a siliceousopalinecement or with a carbonate cement, occasionally sandy, or highly glauconitic, sometimes marly, with many sponges (body fossils, spicules, cement with chalcedony, "spongolites"..). In this group all the lithological units formerly described as "meules" are assembled, from bottom to top:

- Pommeroeul Fm.: conglomerates and sands;

- Harchies Fm.: mainly conglomerates;

- Catillon Fm.: marls and sands;

- Bracquegnies Fm.: glauconitic conglomerates;

- Bernissart Fm.: granular limestones

(details below).

Stratotype: The Harchies pit exposes most of the Group (Marlière, 1939).

Area: The western part of the Mons Basin. In the eastern part the Group is represented by facies with sands and glauconitic gravel with a chalcedony cement  ("gaizes").

This Group is mainly known in abandoned mine shafts and boreholes.

Thickness: May reach 150 m in subsiding zones of the western Mons Basin (Harchies).

Age: The fossil assemblages indicate a Middle Albian to Early Cenomanian age.

Remarks: - the Bracquegnies, Catillon and Harchies fms were united in a "Groupe du Hainaut" by Marlière & Robaszynski (1975).  This name was pre-occupied by a “Groupe du Hainaut” proposed by the same authors to denote Wealden facies. Here, the new term "Haine Group" has a wider meaning and includes the similar facies of the Pommeroeul Greensand Fm. and the Bernissart Calcirudites Fm. Thus the "Haine Group" is closer to the "meules" concept as previously used.

- References: Marlière (1936a, b, 1939, 1954); Marlière & Robaszynski (1975).