The Maastricht Formation ( Dutch: ''Formatie van Maastricht''; abbreviation: MMa), named after the city of Maastricht in the Netherlands, is a geological

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondary ...

in the Netherlands and Belgium whose strata date back to the Late Cretaceous, within 500,000 years of the

Cretaceous–Paleogene boundary The Cretaceous–Paleogene (K–Pg) boundary, formerly known as the Cretaceous–Tertiary (K–T) boundary, is a geological signature, usually a thin band of rock containing much more iridium than other bands. The K–Pg boundary marks the end of ...

, now dated at . The formation is part of the

Chalk Group The Chalk Group (often just called the Chalk) is the lithostratigraphic unit (a certain number of rock strata) which contains the Upper Cretaceous limestone succession in southern and eastern England. The same or similar rock sequences occur acr ...

and is between thick. It crops out in southern parts of Dutch and Belgian Limburg and adjacent areas in Germany. It can be found in the

subsurface In geology, bedrock is solid rock that lies under loose material (regolith) within the crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface material. An exposed portion of bedro ...

of northern Belgium and southeastern Netherlands, especially in the

Campine Basin The Campine (French ) or De Kempen (Dutch ) is a natural region situated chiefly in north-eastern Belgium and parts of the south-eastern Netherlands which once consisted mainly of extensive moors, tracts of sandy heath, and wetlands. It encomp ...

and

Roer Valley Graben The Rur or Roer (german: Rur ; Dutch and li, Roer, , ; french: Rour) is a major river that flows through portions of Belgium, Germany and the Netherlands. It is a right (eastern) tributary to the Meuse ( nl, links=no, Maas). About 90 perce ...

. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 588-593. .

Lithology

The Maastricht Formation consists of soft, sandy shallow

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

limestone (in Limburg locally called " mergel"), in fact chalk and calcareous arenite. These lithologies locally alternate with thin bands of

marl Marl is an earthy material rich in carbonate minerals, clays, and silt. When hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae. Marl makes up the lower part o ...

or clay. The lower parts of the formation contain flint concretions. The upper parts can have shellrich layers. Its age is between about 70 and 66 million years, which puts it in the Maastrichtian, a stage that was named after the formation. The top of the formation has been identified as Danian (early Paleocene) in age. The

type locality Type locality may refer to: * Type locality (biology) * Type locality (geology) See also * Local (disambiguation) * Locality (disambiguation) {{disambiguation ...

is at the ruins of Lichtenberg castle on Mount Saint Peter, Maastricht.

Stratigraphy

The Maastricht Formation was first described by Belgian geologist André Dumont in 1849. The formation is subdivided in seven members, from top to bottom these are the Meerssen Member, Nekum Member, Emael Member, Schiepersberg Member, Gronsveld Member, Valkenburg Member and Kunrade Member. The members are often hard to distinguish.See for example
Stratigraphy of the ENCI quarry
by H. Zevenberg The Maastricht Formation is overlain by the Paleocene

Houthem Formation 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 co ...

and was deposited on top of the older

Gulpen Formation Gulpen (; li, Gullepe ) is a village in the Dutch province of Limburg. It is approximately midway between the Dutch city of Maastricht and the German city of Aachen. Gulpen was a separate municipality until 1999, when it merged with Wittem. The ...

Vertebrate paleofauna

Dinosaurs

Mammals

Mosasaurs

Testudines

* ''Glyptochelone suyckerbuyki'' * ''Allopleuron hoffmani''

References

{{DEFAULTSORT:Maastricht Geologic formations of the Netherlands Geologic formations of Belgium Upper Cretaceous Series of Europe Mesozoic Belgium Cretaceous Netherlands Cretaceous–Paleogene boundary Paleocene Series of Europe Paleogene Belgium Paleogene Netherlands Danian Stage Chalk Open marine deposits Fossiliferous stratigraphic units of Europe Paleontology in the Netherlands

Formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondary ...