Since the rock formation contains both types of fossils the ago of the rock formation must be in the overlapping date range of 415 to 420 million years.
The Wheeler Formation has been previously dated to approximately 507 million year old, so we know the trilobite is also about 507 million years old. Selector .selector_input_interaction .selector_input. Selector .selector_input_interaction .selector_spinner. There are two main methods determining a fossils age, relative dating and absolute dating.If a radioactive isotope is said to have a half-life of 5,000 years that means after 5,000 years exactly half of it will have decayed from the parent isotope into the daughter isotopes.Then after another 5,000 years half of the remaining parent isotope will have decayed.