The Serpukhovian is in Earth's history the top chronostratigraphic stage of Mississippiums ( Carboniferous). The level ranges in absolute geochronological from about 330.9 million to about 323.2 million years. The stage following the Viseum and is detached from the Bashkirian.
Naming and history
The stage is named after the city of Serpukhov near Moscow ( Russia).
Definition and GSSP
The lower boundary of the stage is defined by the first appearance of the conodont species Lochriea crusiformis. The stage and therefore the Mississippian ends with the first appearance of the conodont species Declinognathodus nodiliferus sl An official reference profile of the International Commission on Stratigraphy ("Global Stratotype Section and Point" ) for the Serpukhovian is not yet established.
The Serpukhovian is divided into four conodont zones:
- Gnathodus postbilineatus zone
- Gnathodus bollandensis zone
- Lochria cruciformis zone
- Lochria ziegleri zone