Tongeren Formation
Encyclopedia
The Tongeren Formation is a geologic formation in the subsurface
of the Netherlands
. The formation consists of shallow marine
, epicontinental and continental
sediments, predominantlyy clay
and sand
from the late Eocene
and early Oligocene
epochs
(between 37 and 30 million years old). The Tongeren Formation is part of the Middle North Sea Group
and correlates with the Tongeren Group
from Belgian
stratigraphy
.
The name was introduced by Belgian geologist André Hubert Dumont in 1849.
the Tongeren Formation is lies on top of formations of the Lower North Sea Group
(in particular the late Paleocene
to early Eocene Dongen Formation
and Landen Formation
) or the Dutch Chalk Group (represented by the Late Cretaceous
to early Paleocene Vaals Formation, Gulpen Formation and Houthem Formation
).
In most places, the late Oligocene, marine sands and clays of the Rupel Formation
are found on top of the Tongeren Formation.
website
Subsurface
Subsurface is the seventh studio album by British progressive metal band Threshold. The album was released in August 2004, and received an Album of the Month award in several European music magazines....
of the Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
. The formation consists of shallow marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...
, epicontinental and continental
Continent
A continent is one of several very large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents—they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia.Plate tectonics is...
sediments, predominantlyy clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
and sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
from the late Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
and early Oligocene
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...
epochs
Epoch (geology)
An epoch is a subdivision of the geologic timescale based on rock layering. In order, the higher subdivisions are periods, eras and eons. We are currently living in the Holocene epoch...
(between 37 and 30 million years old). The Tongeren Formation is part of the Middle North Sea Group
Middle North Sea Group
The Middle North Sea Group is a group of geologic formations in the Dutch subsurface, part of the North Sea Supergroup. The three formations of this group form a thick sequence of sediments in the Dutch subsurface, they crop out in parts of the southern Netherlands...
and correlates with the Tongeren Group
Tongeren Group
The Tongeren Group is a lithostratigraphic unit in the subsurface of Belgium. It consists of shallow marine, epicontinental and/or continental clays and sands from the late Eocene to early Oligocene epochs .The Belgian Tongeren Group correlates with the Dutch Tongeren Formation...
from Belgian
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
stratigraphy
Stratigraphy
Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....
.
The name was introduced by Belgian geologist André Hubert Dumont in 1849.
Lithologies and subdivision
The Tongeren Formation is subdivided into three members:- the Goudsberg Member, an alternation of clay with chertChertChert is a fine-grained silica-rich microcrystalline, cryptocrystalline or microfibrous sedimentary rock that may contain small fossils. It varies greatly in color , but most often manifests as gray, brown, grayish brown and light green to rusty red; its color is an expression of trace elements...
nodules and thin ligniteLigniteLignite, often referred to as brown coal, or Rosebud coal by Northern Pacific Railroad,is a soft brown fuel with characteristics that put it somewhere between coal and peat...
layers; - the Klimmen Member, micaMicaThe mica group of sheet silicate minerals includes several closely related materials having highly perfect basal cleavage. All are monoclinic, with a tendency towards pseudohexagonal crystals, and are similar in chemical composition...
ceous fine sand; and - the Zelzate Member, shallow marine glauconiferousGlauconiteGlauconite is an iron potassium phyllosilicate mineral of characteristic green color with very low weathering resistance and very friable.It crystallizes with a monoclinic geometry...
sand alternating with clay layers.
Stratigraphic position
In southern LimburgLimburg (Netherlands)
Limburg is the southernmost of the twelve provinces of the Netherlands. It is located in the southeastern part of the country and bordered by the province of Gelderland to the north, Germany to the east, Belgium to the south and part of the west, andthe Dutch province of North Brabant partly to...
the Tongeren Formation is lies on top of formations of the Lower North Sea Group
Lower North Sea Group
The Lower North Sea Group is a group of geologic formations in the subsurface of the Netherlands and adjacent parts of the North Sea....
(in particular the late Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...
to early Eocene Dongen Formation
Dongen Formation
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.-Lithology and stratigraphy:...
and Landen Formation
Landen Formation
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...
) or the Dutch Chalk Group (represented by the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...
to early Paleocene Vaals Formation, Gulpen Formation and Houthem Formation
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...
).
In most places, the late Oligocene, marine sands and clays of the Rupel Formation
Rupel Formation
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....
are found on top of the Tongeren Formation.
Literatuur
; 1849: Rapport sur la Carte géologique du Royaume, Bulletin de l'Académie royale de Belgique 16 (2ième partie), p. 370. ; 1975: Lithostratigrafie van de Mio-Oligocene afzettingen in Zuid-Limburg, in: (eds.): Toelichting bij geologische overzichtskaarten van Nederland, Rijks Geologische Dienst, Haarlem, pp. 56–63.External links
; 2003: Formatie van Tongeren, TNONetherlands Organisation for Applied Scientific Research
Nederlandse Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek or TNO is a not-for-profit organization in the Netherlands that focuses on applied science. The main office of TNO is located in Delft...
website