The Rupel Formation is a geologic formation in the subsurface

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...

 that consists of 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...

 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...

 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...

s and 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...

s. The Rupel 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

Correlation

In statistics, dependence refers to any statistical relationship between two random variables or two sets of data. Correlation refers to any of a broad class of statistical relationships involving dependence....

 exactly with the 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...

 Rupel Group

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.-Name:...

.

Name

The Rupel Formation was first described by André Hubert Dumont in 1849. The formation is taken from Belgian lithostratigraphy, although it is considered a group in Belgium. The age in which the formation formed is the Rupelian

Rupelian

The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene epoch/series. It spans the time between and . It is preceded by the Priabonian stage and is followed by the Chattian stage....

 (34 to 28 million years ago), a subdivision of the Oligocene epoch. The age and the formation are both named after the Belgian river Rupel

Rupel

The Rupel is a tidal river in northern Belgium, right tributary of the Scheldt. It is about 12 km long. It flows through the Belgian province Antwerp. It is formed by the confluence of the rivers Dijle and Nete, in Rumst. It flows into the Scheldt at Rupelmonde. Towns along the Rupel are...

.

Facies and lithologies

The Rupel Formation can be 250 meters thick at maximum. During the Rupelian age the Netherlands (and Belgium) were covered by a shallow sea, which became deeper towards the northwest. In the northwest, the sedimentary facies can be more than 500 m deep marine, while in southeastern parts of the Netherlands the formation has a near coastal facies.

The formation is subdivided in four members: the Bilzen Member (yellow-white glauconiferous

Glauconite

Glauconite is an iron potassium phyllosilicate mineral of characteristic green color with very low weathering resistance and very friable.It crystallizes with a monoclinic geometry...

 fine sand, containing fossils), the Boom Member (a thick clay deposit, containing loam

Loam

Loam is soil composed of sand, silt, and clay in relatively even concentration . Loam soils generally contain more nutrients and humus than sandy soils, have better infiltration and drainage than silty soils, and are easier to till than clay soils...

 layers and septaria), the Eigenbilzen Member (strongly layered sands) and the Ratum Member (sand, clay and loam, appears only in the east of the Netherlands).

Stratigraphy

In the southwest of the Netherlands the Rupel Formation lies stratigraphically on top of 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...

 to early Oligocene Tongeren Formation

Tongeren Formation

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...

. Further east the Rupel Formation is found on top of the Eocene sands of the 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:...

. In the east, on the Middel-Netherlands High, the base of the formation can also be a nonconformity

Nonconformity

Nonconformity may refer to:* Nonconformity , a memoir by Nelson Algren, published posthumously in 1992* Nonconformity , a term in quality management* A type of unconformity in geology...

 with Mesozoic

Mesozoic

The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...

 deposits.

In some places the younger Veldhoven Formation

Veldhoven Formation

The Veldhoven Formation is a geologic formation in the subsurface of the Netherlands. The formation consists of an alternation of marine clay and sand from the Oligocene epoch.-Lithology:...

 lies conformily on top of the Rupel Formation. In other places the top of the Rupel Formation is a hiatus, on which Neogene

Neogene

The Neogene is a geologic period and system in the International Commission on Stratigraphy Geologic Timescale starting 23.03 ± 0.05 million years ago and ending 2.588 million years ago...

 formations (such as the Breda Formation

Breda Formation

The Breda Formation is a geologic formation in the subsurface of the Netherlands. The formation consists of marine glauconiferous sands and clays that were deposited during the Miocene epoch...

 or Naaldwijk Formation) can be found.

External links

; 2003: Formatie van Rupel, TNO

Netherlands 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