Tielt Formation

Tielt Formation
Stratigraphic range: Ypresian ~53 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Unit of	Ieper Group
Sub-units	Egemkapel & Kortemark Members
Underlies	Hyon Formation
Overlies	Kortrijk Formation
Thickness	up to 25 m (82 ft)
Lithology
Primary	Sandstone
Location
Region	Hainaut, West-, East Flanders, Flemish & Walloon Brabant
Country	Belgium
Extent	Campine Basin
Type section
Named for	Tielt
Region	West Flanders

The Tielt Formation (Dutch: Formatie van Tielt; French: Formation de Tielt; abbreviation: Tt; named after the town of Tielt in West Flanders) is a geologic formation in the subsurface of Belgium. The formation crops out in the north of Hainaut, in the southern and central parts of West- and East Flanders and in Walloon and Flemish Brabant. It consists of marine very fine sand and silt, deposited in the shallow sea that covered Belgium during the middle and late Ypresian age (early Eocene, about 53 million years ago).^[1][2]