The information on this page is a summary description.
The full formal description is available here: Tielt Formation
| Abbreviation | Tt |
| Parent unit | Ieper Group |
| Child units | Kortemark Member, Egemkapel Member |
| Lithological description | This marine unit consists in general of a very fine sandy, coarse silt and clay. |
| Age | Middle to Late Ypresian. |
| Thickness | Maximum 25 m in the centre of the outcrop area. It decreases to the south and the east, and probably to the north. |
| Area of occurrence | The western and northern part of Belgium. The formation outcrops in the north of Hainaut, the south and the centre of East‐ and West‐Flanders and the western and southwestern part of Brabant. Outliers occur in the Mons Basin and south of the river Sambre. The regional distribution map of the Tielt Formation is figured in Maréchal, R. (1993, p 222), Walstra et al. (2014) and in https://dov.vlaanderen.be |
| Type locality | At its base the formation is defined by the top of the Aalbeke Member (see Aalbeke Member). In the compendium this boundary is placed at 48.5m in the Tielt 053E0061 borehole (see also Aalbeke Member). Steurbaut (1998) defined a boundary in the Tielt 068E0169 borehole in which the Aalbeke top was located at 71 m (see also Geets, 2000) which is different from the present definition (see Aalbeke Member). Steurbaut (1998) correlated the in‐the‐present‐text defined top of the Aalbeke Member with the top of his unit D in the Kortemark silt Member (sensu Steurbaut 1998) of the Tielt 068E0169 borehole located at 46.7 m ( Sheet 21/6 (Wakken). Coordinates: x =76439, y = 187576, z = +48 m). The upper boundary is placed at the base of the Egem Mbr in the “Ampe/Egem” quarry ‐ 053W0060 (see Steurbaut, 1998 Figs 5,11). Sheet 21/1 (Wingene). Co‐ordinates: x = 70.150, y = 190.150, z = +44 m. |
| Alternative names | |
| Authors | Steurbaut, E., De Ceukelaire, M., Lanckacker, T., Matthijs, J., Stassen, P., Van Baelen, H. & Vandenberghe, N. |
| Date | 09/01/2017 |
| Cite as | Steurbaut, E., De Ceukelaire, M., Lanckacker, T., Matthijs, J., Stassen, P., Van Baelen, H. & Vandenberghe, N., 2017. The Tielt Formation, 09/01/2017. National Commission for Stratigraphy Belgium. http://ncs.naturalsciences.be/lithostratigraphy/Tielt-Formation |
