The Houthem Formation, named after the Dutch town of Houthem, is a geological formation that crops out in the south of Belgian and Dutch Limburg. It has also been found in borings in the northeastern part of the Campine Basin. The formation consists of calcareous sandstone and was formed about 60 million years ago, in the Paleocene epoch.
The Hesbaye Group is a stratigraphic group in the subsurface of northeastern Belgium. This group was deposited during the early Paleocene epoch and is subdivided into two formations: the Houthem Formation (lower) and the Opglabbeek Formation (upper). The group is named after the region of Hesbaye in the south of Limburg.
The Landen Formation is a lithostratigraphic unit in the subsurface of the Netherlands. This formation shares its name with the Belgian Landen Group, but the Belgian unit is thinner and has different definitions. The Landen Formation consists of shallow marine and lagoonal sediments from the late Paleocene to early Eocene. Dutch stratigraphers see the Landen Formation as part of the Lower North Sea Group.
The Heers Formation is a geologic formation in the subsurface of Belgium. The formation consists of sand and marl and was deposited in the shallow sea that covered Belgium during the middle to late Selandian age of the Paleocene epoch.
The Landen Group is a lithostratigraphic unit in the Belgian subsurface. The group consists of two formations of Thanetian to Ypresian age. The Landen Group is named after the town of Landen in Flemish Brabant.
The Tienen Formation is a geologic formation in the subsurface of northern Belgium. The formation crops out in the province of Hainaut and the Hesbaye region in the province of Limburg. It has a late Thanetian (Paleocene) to early Ypresian (Eocene) age.
The Ieper Group is a group of rock strata in the subsurface of northwest Belgium. The group is subdivided into three marine formations, all formed during the Ypresian, a single age of the geologic timescale. Both age and group are named after the West Flemish town of Ypres, for which the Dutch name is "Ieper".
The Dongen Formation is a geologic formation in the subsurface of the Netherlands. The formation consists of early Eocene marine clay and sand. It is named after the town of Dongen in North Brabant.
The Rupel Formation is a geologic formation in the subsurface of the Netherlands that consists of Oligocene marine sands and clays. The Rupel Formation is part of the Middle North Sea Group and correlates exactly with the Belgian Rupel Group.
The Rupel Group is a stratigraphic group of rock strata in the subsurface of Belgium. It is subdivided into three formations that are all marine deposits of Oligocene age.
The Zenne Group is a group of rock strata in the subsurface of central and northwest Belgium. The group consists of three formations, all from the Ypresian and Lutetian ages. These formation have their shallow marine facies in common.
The Tongeren Formation is a geologic formation in the subsurface of the Netherlands. The formation consists of shallow marine, epicontinental and continental sediments, predominantly clay and sand from the late Eocene and early Oligocene epochs. The Tongeren Formation is part of the Middle North Sea Group and correlates with the Tongeren Group from Belgian stratigraphy.
The Aalter Formation is a geologic formation in the subsurface of northwest Belgium. The formation consists of marine clay and sand, deposited in the shallow sea that covered northern and central Belgium in the Eocene epoch.
The Gentbrugge Formation is a geologic formation in the west of Belgium. The formation crops out in East Flanders and West Flanders and also occurs in the subsurface of the Province of Antwerp. It consists of marine clay, silt and sand, deposited in the shallow sea that covered northern Belgium during the Ypresian age.
The Tielt Formation 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.
The Kortrijk Formation is a geologic formation in the Belgian subsurface. This formation crops out in northern Hainaut, southern West and East Flanders and in Walloon Brabant. The formation consists of marine clay from the Ypresian age.
The Voort Formation or Voort Member is a stratigraphic unit in the subsurface of north Belgium and the south of the Netherlands. The unit has the status of a formation in Belgium but is seen as a member of the Veldhoven Formation in the Netherlands. The Voort Formation consists of shallow marine sands with a late Oligocene age.
The Maldegem Formation is a geologic formation in the Belgian subsurface. The formation consists of alternating marine clay and sand strata, deposited during the late Eocene.
The Brussel Formation is a geologic formation in the subsurface of central Belgium. The formation is named after the Belgian capital, Brussels. It consists of shallow marine sandstone and calcareous sands, deposited in the sea that covered Belgium 45 million years ago, in the Eocene.
The Lede Formation is a geologic formation in the subsurface of Belgium. The formation is named after the town of Lede in East Flanders. It consists of shallow-marine limestone and sandstone, deposited in the former sea that covered Belgium during the Eocene.
