The Breda Formation ( nl, Formatie van Breda; abbreviation: BR) is a

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

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 the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

. The formation consists of

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 * ...

glauconiferous

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a soil texture, textur ...

s and

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay part ...

s that were deposited during the

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ...

epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by ...

. Although the formation is not very rich in fossils, sometimes bones of

fishes Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of liv ...

, mammals ( ''Leptophoca'' cf. ''proxima'', '' Protophocaena minima''),Liessel
at

Fossilworks Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was cre ...

.org

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses ** Thin-shell structure Science Biology * Seashell, a hard o ...

s and

shark teeth Sharks continually shed their teeth; some Carcharhiniformes shed approximately 35,000 teeth in a lifetime, replacing those that fall out. There are four basic types of shark teeth: dense flattened, needle-like, pointed lower with triangular upp ...

(a.o of

megalodon Megalodon (''Otodus megalodon''), meaning "big tooth", is an extinct species of mackerel shark that lived approximately 23 to 3.6 million years ago (Mya), from the Early Miocene to the Pliocene epochs. It was formerly thought to be a me ...

) are found.

Stratigraphy and lithology

The Breda Formation was deposited in the shallow sea that covered the

during the Miocene. It is mostly on top of the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

clays of the

Rupel Formation The Rupel Formation (abbreviation: RU) 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 Belgi ...

or late Oligocene sands and clays of the

Veldhoven Formation The Veldhoven Formation ( nl, Formatie van Veldhoven; abbreviation: VE) 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 The Veldhove ...

. The Breda Formation can be a couple of meters (in the Roerdal Graben) to more than thick. The top is formed by an

erosion Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is di ...

disconformity An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval o ...

in the south and east of the Netherlands. In the west the contact with the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Oosterhout Formation The Oosterhout Formation is a geological formation in the subsoil in the central and south area of the Netherlands. The formation was formed during the Pliocene (5.333 million to 2.58 million years BP). The formation was named after the city of Oo ...

is more gradual. In the Roerdal Graben the mostly Pliocene Kiezeloolite Formation is sometimes on top of the Breda Formation. Locally the Breda Formation can be subdivided into

members Member may refer to: * Military jury, referred to as "Members" in military jargon * Element (mathematics), an object that belongs to a mathematical set * In object-oriented programming, a member of a class ** Field (computer science), entries in ...

: the Aalten Member (

silt Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water. Silt usually has a floury feel wh ...

y calcareous clay, rich in shells), the Eibergen Member (clay alternating with thin sand layers, with a basal conglomerate in which shark teeth and

whale Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and ...

bones were found), the Zenderen Member (green, glauconiferous fine sand) and the Delden Member (sandy, glauconite and

goethite Goethite (, ) is a mineral of the diaspore group, consisting of iron(III) oxide-hydroxide, specifically the "α" polymorph. It is found in soil and other low-temperature environments such as sediment. Goethite has been well known since ancient ...

bearing clay and

loam Loam (in geology and soil science) is soil composed mostly of sand ( particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–si ...

. The Breda Formation corresponds largely with the

Berchem Formation Berchem () is a southern Districts of Antwerp, district of the municipality and city of Antwerp in the Flemish Region of Belgium. Berchem is located along the old ''Grote Steenweg'' (Dutch language, Dutch for 'Big Paved Road') that has connected ...

of northern

Belgium Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to ...

References

Bibliography

* ; 1975: ''Formaties van het Kwartair en Boven-Tertiair in Nederland'', in: (''eds.''): ''Toelichting bij geologische overzichtskaarten van Nederland'', Rijks Geologische Dienst, Haarlem, pp. 11–56. ()

External links

* ; 2003
Formatie van Breda
TNO website {{DEFAULTSORT:Breda Lithostratigraphy of the Netherlands Miocene geology Neogene Europe Breda Formation Sandstone formations Fossiliferous stratigraphic units of Europe Paleontology in the Netherlands