Piacenzian

The Piacenzian is a stage of the Pliocene Epoch in the modern geologic time scale (International Commission on Stratigraphy). It is the latter of the two Pliocene stages, succeeding the Zanclean and preceding the Gelasian, and roughly spans from about 3.6 million to 2.58 million years ago. The name derives from the Italian city of Piacenza, a practice common in early stratigraphy of naming stages after locality features.

Stratigraphic boundaries and dating

The Piacenzian begins at the close of the Zanclean and ends at the base of the Gelasian. While exact boundary definitions are tied to global stratigraphic markers, the approximate radiometric ages are widely used: about 3.6 million years ago at the lower limit and about 2.58 million years ago at the upper limit. The Piacenzian is therefore the late Pliocene in the ICS timescale.

Climate and environment

The Piacenzian was a time of gradual cooling and increasing climatic variability compared with earlier Pliocene conditions. Global temperatures declined, weather patterns became more seasonal, and indications of growing ice volume in the hemispheres emerged. These changes contributed to shifts in ocean circulation, vegetation, and habitats, setting the stage for the widespread glaciations of the following Pleistocene.

Fossil record and significance

The Piacenzian preserves important mammal, flora, and marine faunas that document the transition toward cooler, more arid conditions in many regions. Its biostratigraphic and geochemical records help illuminate late Cenozoic climate dynamics and the ecological contexts in which early hominins and other modern lineages began to evolve.

Overall, the Piacenzian marks the late phase of the Pliocene, a pivotal interval leading into the Pleistocene.