The Danian is the oldest
age or lowest
stage
Stage or stages may refer to:
Acting
* Stage (theatre), a space for the performance of theatrical productions
* Theatre, a branch of the performing arts, often referred to as "the stage"
* ''The Stage'', a weekly British theatre newspaper
* Sta ...
of the
Paleocene
The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''pal ...
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 ...
or
Series
Series may refer to:
People with the name
* Caroline Series (born 1951), English mathematician, daughter of George Series
* George Series (1920–1995), English physicist
Arts, entertainment, and media
Music
* Series, the ordered sets used in ...
, of the
Paleogene Period
Period may refer to:
Common uses
* Era, a length or span of time
* Full stop (or period), a punctuation mark
Arts, entertainment, and media
* Period (music), a concept in musical composition
* Periodic sentence (or rhetorical period), a concept ...
or
System, and of the
Cenozoic Era
An era is a span of time defined for the purposes of chronology or historiography, as in the regnal eras in the history of a given monarchy, a calendar era used for a given calendar, or the geological eras defined for the history of Earth.
Comp ...
or
Erathem
__NOTOC__
In stratigraphy, paleontology, geology, and geobiology an erathem is the total stratigraphic unit deposited during a certain corresponding span of time during an era in the geologic timescale.
It can therefore be used as a chronostra ...
. The beginning of the Danian (and the end of the preceding
Maastrichtian
The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval ...
) is at the
Cretaceous–Paleogene extinction event
The Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary extinction) was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago. With the ...
. The age ended , being followed by the
Selandian
The Selandian is a stage in the Paleocene. It spans the time between . It is preceded by the Danian and followed by the Thanetian. Sometimes the Paleocene is subdivided in subepochs, in which the Selandian forms the "middle Paleocene".
Stratig ...
.
Stratigraphic definitions
![Main floristic types from the Danian - journal](https://upload.wikimedia.org/wikipedia/commons/4/47/Main_floristic_types_from_the_Danian_-_journal.pone.0052455.g007-right.png)
The Danian was introduced in scientific literature by
German
German(s) may refer to:
* Germany (of or related to)
** Germania (historical use)
* Germans, citizens of Germany, people of German ancestry, or native speakers of the German language
** For citizens of Germany, see also German nationality law
**Ge ...
-
Swiss geologist
Pierre Jean Édouard Desor
Pierre Jean Édouard Desor (13 February 1811, Friedrichsdorf, Grand Duchy of Hesse23 February 1882) was a German-Swiss geologist and naturalist.
Biography
Desor studied law at Giessen and Heidelberg, was compromised in the republican movements ...
in 1847 following a study of fossils found in France and Denmark.
[Danien](_blank)
Den Store Danske Encyklopædi
''Den Store Danske Encyklopædi'' (''The Great Danish Encyclopedia'') is the most comprehensive contemporary Danish language encyclopedia. The 20 volumes of the encyclopedia were published successively between 1994 and 2001; a one-volume suppleme ...
He identified this stage in deposits from
Faxe
Faxe or Fakse is a town on the island of Zealand in eastern Denmark. It is located in Faxe Municipality in Region Zealand. The town is most known for the Faxe Brewery, Royal Unibrew, a relatively large brewery producing a range of beer and soft ...
and
Møns Klint
Møns Klint is a 6 km stretch of limestone and chalk cliffs along the eastern coast of the Danish island of Møn in the Baltic Sea. Some of the cliffs fall a sheer 120 m to the sea below. The highest cliff is , which is 128 m above sea le ...
and named it after the
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
name for
Denmark
)
, song = ( en, "King Christian stood by the lofty mast")
, song_type = National and royal anthem
, image_map = EU-Denmark.svg
, map_caption =
, subdivision_type = Sovereign state
, subdivision_name = Kingdom of Denmark
, establish ...
.
The
Montian
The Danian is the oldest age or lowest stage of the Paleocene Epoch or Series, of the Paleogene Period or System, and of the Cenozoic Era or Erathem. The beginning of the Danian (and the end of the preceding Maastrichtian) is at the Cretace ...
Stage from
Belgian
Belgian may refer to:
* Something of, or related to, Belgium
* Belgians, people from Belgium or of Belgian descent
* Languages of Belgium, languages spoken in Belgium, such as Dutch, French, and German
*Ancient Belgian language, an extinct languag ...
stratigraphy (named after the city of
Mons) is now known to be roughly equivalent to the Upper Danian and is considered a
junior synonym and is no longer in use.
The base of the Danian is defined at the
iridium anomaly
The term iridium anomaly commonly refers to an unusual abundance of the chemical element iridium in a layer of rock strata at the Cretaceous–Paleogene (K–Pg) boundary. The unusually high concentration of a rare metal like iridium is often tak ...
which characterized the
Cretaceous–Paleogene boundary (K–T boundary) in stratigraphic sections worldwide. A section in
El Kef
El Kef ( ar, الكاف '), also known as ''Le Kef'', is a city in northwestern Tunisia. It serves as the capital of the Kef Governorate.
El Kef is situated to the west of Tunis and some east of the border between Algeria and Tunisia. It has a ...
,
Tunisia
)
, image_map = Tunisia location (orthographic projection).svg
, map_caption = Location of Tunisia in northern Africa
, image_map2 =
, capital = Tunis
, largest_city = capital
, ...
was appointed as a reference profile (
GSSP
A Global Boundary Stratotype Section and Point (GSSP) is an internationally agreed upon reference point on a stratigraphic section which defines the lower boundary of a stage on the geologic time scale. The effort to define GSSPs is conducted ...
) for this important boundary. The Danian is the oldest age of the Paleocene, defined at its base by the K-Pg boundary. It is very important because the readily recognized iridium anomaly and primitive Danian planktonic foraminifers define the base of the Danian. Danian
foraminiferans
Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular ectoplasm for catching food and other uses; and commonly an ...
repopulated the Paleocene seas after the Cretaceous mass extinction (Olsson et al., 1996). The first replacement foraminiferan of the Paleogene is the ''Globigerina eugubina,'' which is used to define the base of the Danian Age (Stainforth et al., 1975). This foraminiferan replaced the Cretaceous genus ''Globotruncana''.
The top of the Danian Stage (the base of the Selandian) is close to the boundary between
biozone
In biostratigraphy, biostratigraphic units or biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa, as opposed to a lithostratigraphic unit which is defined by the lithological properties ...
s NP4 and NP5 from marine
biostratigraphy
Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them.Hine, Robert. “Biostratigraphy.” ''Oxford Reference: Dictionary of B ...
. It is slightly after the first appearances of many new species of the calcareous
nanoplankton
Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a cruc ...
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
''Fasciculithus'' (''F. ulii'', ''F. billii'', ''F. janii'', ''F. involutus'', ''F. tympaniformis'' and ''F. pileatus'') and close to the first appearance of calcareous
nanoplankton
Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a cruc ...
species ''Neochiastozygus perfectus''.
The Danian Stage overlaps the
Puercan
The Puercan North American Stage on the geologic timescale is the North American faunal stage
In chronostratigraphy, a stage is a succession of rock strata laid down in a single age on the geologic timescale, which usually represents millions ...
and
Torrejonian North American land mammal ages and the Shanghuan and lowest part of the Nongshanian
Asian land mammal ages
The Asian land mammal ages, acronym ALMA, establish a geologic timescale for prehistoric Asian fauna beginning 58.7 Mya during the Paleogene and continuing through to the Miocene ( Aquitanian) (23.03 Ma). These periods are referred to as ages, s ...
. It includes the oldest
Mammal Paleogene zones
The Mammal Paleogene zones or MP zones are system of biostratigraphy, biostratigraphic biozone, zones in the stratigraphic record used to correlate mammal-bearing fossil localities of the Paleogene period of Europe. It consists of thirty consecutiv ...
, all included in the 1 - 5 group.
Paleontology
Though the non-avian
dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...
s were gone, the mammals and other land animals remained small, most not even bigger than a sheep; however; a few (like ''
Ankalagon saurognathus)'' reached the size of a medium-sized bear. Numerous lineages of
modern birds
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...
also survived, particularly in the area around
Australia but also elsewhere, e.g. ''
Scaniornis'' of the
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea, epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the ...
region. The oceans remained much the same as the
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...
seas, only that there was less life, few remaining marine
reptiles (mostly
turtle
Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked t ...
s,
choristodera and
crocodiles), and other lesser-known animals.
There are
controversial reports of
ammonites
Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttl ...
(mainly of the
Scaphitidae
Scaphitidae is a family of extinct cephalopods belonging to the family of heteromorph ammonites (suborder Ancyloceratina). There is a possible fossil record of them being the last ammonites with fossils dating to the Danian of the Paleocene in D ...
class in
Turkmenistan
Turkmenistan ( or ; tk, Türkmenistan / Түркменистан, ) is a country located in Central Asia, bordered by Kazakhstan to the northwest, Uzbekistan to the north, east and northeast, Afghanistan to the southeast, Iran to the sout ...
) still being around at this time, although they did not survive the Danian age.
Latest Danian Event
Close to the end of the Danian, around 62.2 Ma, occurred a hyperthermal, similar to but smaller in magnitude compared to the more famous
Palaeocene-Eocene Thermal Maximum (PETM), known as the Latest Danian Event (LDE).
The event, which took place over a 170-230 kyr time interval, is evidenced in the geologic record by two negative carbon isotope excursions and is believed to have led to a 2–3 °C warming of both deep and surface seawater.
This hyperthermal also led to a shallowing of the oceanic lysocline, as evidenced by the significant decrease in calcium carbonate preservation.
References
Literature
*; 1847: ''Sur le terrain Danien, nouvel étage de la craie'', Bulletin de la Société Géologique de France, série 2, 3, pp. 179–181, .
*; 2004: ''A Geologic Time Scale 2004'',
Cambridge University Press
Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by King Henry VIII in 1534, it is the oldest university press in the world. It is also the King's Printer.
Cambridge University Pre ...
.
*; 2006: ''The Global Boundary Stratotype Section and Point for the base of the Danian Stage (Paleocene, Paleogene, "Tertiary", Cenozoic) at El Kef, Tunisia: original definition and revision'', Episodes 29(4), pp. 263–273, .
*; 1996:''The Cretaceous-Tertiary catastrophe event at Millers Ferry, Alabama'' in Ryder, G., Fastovsky, D., and Gartner, S., eds., The Cretaceous-Tertiary Event and other catastrophes in Earth history: Geological Society of America Special Paper 307, pp. 263–277.
*; 1975: ''Cenozoic planktonic foraminifera zonation and characteristics of index forms'': The University of Kansas Paleontological Institute, Article 62, 425 p.
External links
GeoWhen Database – DanianPaleogene timescale (2008) at the website of the subcommission for stratigraphic information of the ICS
Stratigraphic chart of the Paleogene (2006) at the website of Norges Network of offshore records of geology and stratigraphy
{{Authority control
Paleocene geochronology
Geological ages