Tithonian

In the geological timescale the Tithonian is the latest age of the Late Jurassic epoch or the uppermost stage of the Upper Jurassic series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma (million years ago). It is preceded by the Kimmeridgian and followed by the Berriasian stage (part of the Cretaceous).

The Tithonian was introduced in scientific literature by German stratigrapher Albert Oppel in 1865. The name Tithonian is unusual in geological stage names because it is derived from Greek mythology. Tithonus was the son of Laomedon of Troy. He fell in love with Eos, the Greek goddess of dawn and finds his place in the stratigraphy because this stage, the Tithonian, finds itself hand in hand with the dawn of the Cretaceous.

The base of the Tithonian stage is at the base of the ammonite biozone of Hybonoticeras hybonotum. A global reference profile (a GSSP or golden spike) for the base of the Tithonian had in 2009 not yet been established.

The top of the Tithonian stage (the base of the Berriasian stage and the Cretaceous system) is marked by the first appearance of small globular calpionellids of the species Calpionella alpina, at the base of the Alpina Subzone .

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