Orleanium
Orleanium (also Orléans stage, or just Orléans) is a regional stage in the terrestrial neogene of Europe. It corresponds to zones MN 3 to 5 of the European land mammal chronology ( ELMMZ = "European Land Mammal Mega-Zones"). It is underlain by the Agenium and overlaid by the Astaracium .
History and type locality
The step is named after the French city Orléans , near which the type locality is located.
definition
The lower limit is defined by the introduction of the large mammal genera Gomphotherium , Procervulus , Lagomeryx , Actoocemas , Palaeomeryx , Brachyodus , Anchitherium , Aureliachoerus , Hemicyon . No corresponding zone fossil has yet been found in small mammals. The stage ends with the first appearance of Tethytragus , Hispanomeryx , Euprox , Listriodon (large mammals) and Megacricetodon crusafonti and Megacricetodon gersi (small mammals). The level is correlated with the chronostratigraphic level of the Burdigalium and the lower Langhium . In geochronology, this corresponds to the period from 20.4 to 15 million years.
Breakdown
The stage is divided into three biozones MN 3, 4 and 5. The level is accordingly divided into Lower, Middle and Upper Orleanium.
literature
- J. Agustí, L. Cabrera, M. Garcés, W. Krijgsman, O. Oms, JM Parés: A calibrated mammal scale for the Neogene of Western Europe. State of the art. Earth Science Reviews, 52: 247-260, Amsterdam 2001 ISSN 0012-8252
- Everett Lindsay: Eurasian mammal biochronology: an overview. Palaeogeography, Palaeoclimatology, Palaeoecology, 133: 117-128, Amsterdam 1997 ISSN 0031-0182