Bajocian — Middle Jurassic age and stage Bajocian The Bajocian is a stage of the Middle Jurassic (about 170.3–168.3 Ma), defined by marine strata and ammonite biozones. It succeeds the Aalenian and precedes the Bathonian.
Radiometric dating Techniques that determine the age of materials by measuring radioactive isotopes and their decay products. Widely used in geology, archaeology and planetary science.
