# How to calculate relative age for Unknown Rock Succession using the known Absolute age of a Known succession

Most of the time we need to identify the accurate date of the new stratigraphic section for new research. Hence, we have to correlate the absolute age with the Global stratotype section and points (GSSP) like Meishan. The correlation is very important and the need precise age calculation

Let’s Calculate the age of the known Bed.

Example from the Meishan section (GSSP)

Age at the Bed 22: 252.104±0.089 Ma

Max : 252.104+0.089 = 252.193 Ma

Min: 252.104-0.089= 252.015 Ma

Age at the Bed 25: 251.941±0.037 Ma

Max: 251.941+0.037= 251.978 Ma

Min: 251.941-0.037= 251.904 Ma

Max (Bed 22) – Min (Bed 25) (largest interval): A = 252.193 Ma-251.904 Ma=0.289 Ma=289 kyrs

Min (Bed 22) – Max (Bed 25) (smallest interval): B= 252.015 Ma-251.978 Ma= 0.037 Ma=37 kyrs

Error = A – B

= 289-37=252 kyrs

(Bed 22 to Bed 25 height is 400 cm and height of isotopic zone A to C is 25 cm)

Age interval of Bed 22 to Bed 25 is:

400 cm = 252.104-251.941= 0.163 Ma=163 kyrs

So. Age interval of isotopic zone A to C= (163*25)/400= 10.1875 kyrs

For error: 400 cm = 252 kyrs

25 cm = (252*25)/400 = 15.75 kyrs

Age interval of A-C is 10.19±15.75 kyrs