The information on this page is a summary description.
The full formal description is available here: Anchamps Formation
| Abbreviation | ANC |
| Parent unit | Revin Group |
| Child units | |
| Lithological description | Formation subdivided into three members: the unnamed lower member (old: Rv3a) black slate, slightly micaceous with a few thin black quartzite beds; the Crapaude-Pierre Member (CRP, old: Rv3b): a few black, pyritic, finegrained quartzite beds, 4 m thick at most; the unnamed upper member (old: Rv3c): alternation of black “psammitic” slates and thin to medium bedded black pyritic quartzite (a few cm to 2 m). Towards the top the beds are increasingly thicker and the slate more and more sandy and micaceous. The boundary with the covering Petite-Commune Fm is placed below the first appearance of a quartzite bed of at least 5 m thickness. Many sedimentary structures of turbidites including convolute bedding are present. The cleavage planes of the slate beds have a polished aspect. Some slate beds contain chloritoids (Beugnies, 1960; Belanger, 1998 ms). |
| Age | Most of the formation contains acritarchs of the Zone 4b, dated as Mid to Late Cambrian (Vanguestaine, 1992). |
| Thickness | 200 to 600 m. The upper member takes up two thirds of the thickness of the formation (Beugnies, 1960). |
| Area of occurrence | Rocroi massif; the Crapaude-Pierre Mbr seems to have a remarkable continuity. |
| Type locality | Not yet defined; type area in the outcrops along the Meuse valley south of Fumay. |
| Alternative names | Rv3 |
| Authors | Verniers, J., Herbosch, A., Vanguestaine, M., Geukes, F., Delcambre, B., Pingot, J.-L., Belanger, I., Hennebert, M., Debacker, T., Sintubin, M. & De Vos, W. |
| Date | 01/01/2001 |
| Cite as | Verniers, J., Herbosch, A., Vanguestaine, M., Geukes, F., Delcambre, B., Pingot, J.-L., Belanger, I., Hennebert, M., Debacker, T., Sintubin, M. & De Vos, W., 2001. The Anchamps Formation, 01/01/2001. National Commission for Stratigraphy Belgium. https://ncs.naturalsciences.be/lithostratigraphy/Anchamps-Formation |
| Additional information |
