European land mammal age

Epoch ICS age ELMMZ Age (Ma)
Miocene Aquitanian Agenian younger
Oligocene Chattian Arvernian 23.03-29.2
Rupelian
Suevian 29.2-33.8
Headonian 33.8-37.2
Eocene Priabonian
Bartonian Robiacian 37.2–42.7
Lutetian
Geiseltalian 42.7-48.5
Grauvian 48.5–50.8
Ypresian
Neustrian 50.8-55.0
Paleocene Thanetian
Cernaysian 55.0-55.9
Subdivision of the Paleogene period into European Land Mammal Mega Zones (ELMMZ).

The European Land Mammal Mega Zones (abbreviation: ELMMZ, more commonly known as European land mammal ages or ELMA) are zones in rock layers that have a specific assemblage of fossils (biozones) based on occurrences of fossil assemblages of European land mammals. These biozones cover most of the Neogene and Paleogene systems (i.e. rock layers which are 65.5 to 2.588 million years old). In cases when fossils of mammals are abundant, stratigraphers and paleontologists can use these biozones as a more practical regional alternative to the stages of the official ICS geologic timescale. European Land Mammal Mega Zones are often also confusingly referred to as ages, stages, or intervals.[1]

Biostratigraphic methods

Mammal zones were, like all biozones, established using geographic place names where fossil materials were obtained. The basic unit of measure is the first/last boundary statement. This shows that the first appearance event of one taxon is known to predate the last appearance event of another. If two taxa are found in the same fossil quarry or at the same stratigraphic horizon, then their age-range zones overlap.

The terrestrial stratigraphy of the Cenozoic is more difficult than that of marine deposits. The geologic timescale of the ICS is therefore based on marine fossils, that don't occur in terrestrial sediments. This makes the correlation of terrestrial deposits with the ICS timescale often difficult. Correlation is possible when marine deposits interfinger with terrestrial deposits (resulting from a series of transgressions and regressions of the sea during deposition), but this isn't the case everywhere. A fine stratigraphic division of the terrestrial record can in most places only be made using fossils of land species. Small mammals are often the best choice as they are quite abundant in the terrestrial record, especially their teeth. Teeth have an even better change of preservation than bones.

The European mammalian biozones were established for the Paleogene (8 zones) and Neogene (7 zones) separately. Some of these, especially for the Neogene, were already established in the 19th century. The Villafranchian was, for example, introduced by Lorenzo Pareto in 1865. A finer subdivision was established by Pierre Mein in 1975, who divided the Neogene in 17 zones, known as the MN zonation, indicated by the letters MN (Mammal Neogene) and a number.

Similarly, a more detailed subdivision for the Paleogene period was established. There are 30 such Mammal Paleogene zones (MP1 to MP30, numbered from old to young).[2]

Neogene European mammal zones

Neogene ELMMZ
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MN 1
MN 2
MN 3
MN 4
MN 5
MN 6
MN 6
MN 9
MN 10
MN 11
MN 12
MN 13
MN 14
MN 15
MN 16
MN 17
MNQ1
 
 
 
 

European Land Mammal Mega Zones most often have their bases at first appearances (FAD, First Appearance Date) of a certain species or genus. The numbers are higher for younger zones. Due to a redefinition of the boundary between the Neogene and Quaternary periods, MN 17 is now in fact considered a Quaternary biozone.

Biozone Small mammals Large mammals
MN 17 Kislangia gusi, Mimomys tornensis, Mimomys pliocaenicus, Mimomys reidi Eucladoceros
MN 16 Kislangia ischus, Mimomys polonicus, Kislangia cappettai, Mimomys hajnackensis Equus (horse), Mammuthus (mammoth), Homotherium, Megantereon, Ursus etruscus,
Pliohyaena perrieri, Gazellospira torticornis, Arvernoceros ardei, Hesperidoceras merlai, Cervus perrieri
MN 15 Mimomys occitanus, Oryctolagus, Mimomys vandemeuleni, Mimomys davakosi Chasmaporthetes lunensis
MN 14 Promimomys, Trilophomys, Celadensia, Castor (beaver) Sus arvernensis, Croizetoceros, Acinonyx, Felis issiodorensis
MN 13 Paraethomys, Rhagapodemnus, Stephanomys, Apodemus, Apocricetus Parabos, Paracamelus, Agriotheirum, Apocricetus, Nyctereutes, Hexaprotodon
MN 12 Parapodemus barbarae, Huerzelerimys turoliensis Pliocervus, Hispanodorcas, Palaeoryx, Occitanomys adroveri, Procapreolus
MN 11 Parapodemus lugdunensis, Huerzelerimys vireti, Occitanomys sondaari Birgerbohlinia, Lucentia
MN 10 Rotundomys, Pliopetaurista, Schreuderia, Progonomys cathalai Hyaenictis almerai, Adcrocuta eximia, Microstonyx major, Tragoportax gaufryi
MN 9 Cricetulodon Hippotherium, Decennatherium, Machairodus
MN 7/8 Megacricetodon ibericus, Megacricetodon gregarius Parachleuastochoerus, Propotamochoerus, Palaeotragus, Protragocerus, Tetralophodon
MN 6 Megacricetodon crusafonti, Megacricetodon gersi Tethytragus, Hispanomeryx, Euprox, Listriodon
MN 5 Megacricetodon collongensis Miotragocerus, Micromeryx, Heteroprox, Hispanotherium
MN 4 Megacricetodon primitivus Bunolistriodon, Dorcatherium, Chalicotherium, Eotragus, Prodeinotherium
MN 3 Gomphotherium, Procervulus, Lagomeryx, Actoocemas, Palaeomeryx, Brachyodus, Anchitherium, Aureliachoerus, Hemicyon
MN 2 Ligerimys, Prolagus, Lagopsis, Ritterneria manca Teruelia, Lorancameryx, Oriomeryx, Pseudaelurus, Xenohyus, Andegameryx, Amphitragulus
MN 1 Rhodanomys schlosseri, Vasseuromys Hyotherium

Other continental mammalian biozones

References

Notes

  1. According to Steininger (1999), it is better to just use ELMMZ's in a biostratigraphic sense
  2. Mammal Paleogene zones, The Paleobiology Database

Literature

External links

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