geologic time
The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronolo ...
Late Pliocene
Late or LATE may refer to:
Everyday usage
* Tardy, or late, not being on time
* Late (or the late) may refer to a person who is dead
Music
* Late (The 77s album), ''Late'' (The 77s album), 2000
* Late (Alvin Batiste album), 1993
* Late!, a pseudo ...
and
Early Pleistocene
The Early Pleistocene is an unofficial epoch (geology), sub-epoch in the international geologic timescale in chronostratigraphy, representing the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently esti ...
Lorenzo Pareto
Lorenzo Nicolò Pareto (Genoa, 6 December 1800 – Genoa, 19 June 1865) was an Italian geologist and statesman.
As a man of science, he is considered one of the fathers of modern geology. A member of the Italian National Academy of Sciences, h ...
for a sequence of terrestrial sediments studied near Villafranca d'Asti, a town near
Turin
Turin ( , ; ; , then ) is a city and an important business and cultural centre in northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. The city is main ...
, it succeeds the Ruscinian age, and is followed by the Galerian.
The Villafranchian is sub-divided into six faunal units based on the localities of Triversa, Montopoli, Saint-Vallier, Olivola, Tasso and Farnetta.The Pleistocene Boundary and the Beginning of the Quaternary edited by John A. Van Couvering. Cambridge University Press 1997
A major division of European geological deposits and time, the Villafranchian is significant because it marked the first arrival of archaic humans into Europe towards the end of the period. The Villafranchian is partially contemporaneous with the
Blancan
The Blancan North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 4,750,000 to 1,806,000 years BP, a period of .
The beginning of the Villafranchian is typically defined by the first appearance of the bovid genus '' Leptobos'' in Italy, dated to around 3.5-3.6 million years ago (mya). The beginning of the Middle Villafranchian is defined by the "elephant–''Equus'' event" denoting the first appearance of the mammoth '' Mammuthus meridionalis'' and the equine '' Equus stenonis,'' thought to be around 2.5-2.6 mya''.'' The beginning of the Late Villafranchian was formerly typically defined by the "Wolf event", the first appearance of '' Canis etruscus ,'' but this was later considered to be
diachronous
In geology, a diachronism ( Greek ''dia'', "through" + ''chronos'', "time" + ''-ism''), or diachronous deposit, is a sedimentary rock formation in which the material, although of a similar nature, varies in age with the place where it was deposite ...
. It was later proposed that the boundary be placed at the first appearance of the giant hyena ''Pachycrocuta brevirostri''s approximately 1.8 mya. The transition between the Villafranchian and the following Galerian has been placed as its own biochron, the Epivillafranchian, coincident with the end of the Early Pleistocene around 1.2-0.9/0.8 million years ago. This period was marked by numerous extinctions, including those of ''Pachycrocuta'', the sabertoothed cat ''
Megantereon
''Megantereon'' is an extinct genus of prehistoric machairodontine saber-toothed cat that lived in Eurasia, Africa and possibly North America from the late Pliocene to the Middle Pleistocene. It is a member of the tribe Smilodontini, and close ...