The information on this page is a summary description.
The full formal description is available here: Jamoigne Formation
Abbreviation
JAM
Parent unit
Child units
Rossignol Member, Muno Member, Warcq Member
Lithological description
Bioturbated dark grey marl with decimetre-thick argillaceous-sandy limestone or sandstone beds (increasingly frequent towards the top of the unit). The Warcq Member, capping the formation at the contact with the Luxembourg Formation, consists of light grey argillaceous sand or sandstone. Locally, micaceous sandstone and gravel beds are observed at the base of the Jamoigne Formation. Fauna and bioturbation are quite abundant.
Age
The Jamoigne Formation is only Hettangian in age in eastern Belgian Lorraine, covering the Psiloceras planorbis, Alsatites liasicus and Schlotheimia angulata ammonite Zones; in the western part, the formation also includes the Warcq Member (Arietites bucklandi Zone) and thus extends into the Lower Sinemurian (Maubeuge, 1954; Mergen, 1984; Guérin-Franiatte & Muller, 1986).
Thickness
Constant thickness of about 45 m. The thickness gradually increases towards the south to reach 70 m in boreholes close to the French border. In the west, the Jamoigne Formation is transgressive on the Rhaetian (Rossignol Member) and on the Palaeozoic basement (Muno Member) with a more arenaceous and fossiliferous facies.
Area of occurrence
The formation outcrops in Belgian Lorraine
Type locality
Latour borehole.
Alternative names
Authors
Boulvain, F., Belanger, I., Delsate, D., Ghysel, P., Godefrout, P., Laloux, M., Monteyne, R. & Roche, M.
Date
01/01/2001
Cite as
Boulvain, F., Belanger, I., Delsate, D., Ghysel, P., Godefrout, P., Laloux, M., Monteyne, R. & Roche, M., 2001. The Jamoigne Formation, 01/01/2001. National Commission for Stratigraphy Belgium. http://ncs.naturalsciences.be/lithostratigraphy/Jamoigne-Formation
