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The ten strata systems that compose the “standard geologic column” are the familiar Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian, Triassic, Jurassic, Cretaceous, and Tertiary periods.

Although no absolute methods were available to establish actual dates, Lyell needed to assign very old dates to the strata to make them consistent with the long eons of time that would be necessary to meet the new uniformitarianism theory developed by James Hutton and himself.

Studying the layers of rock or strata can also be useful. If a layer of rock containing the fossil is higher up in the sequence that another layer, you know that layer must be younger in age. This can often be complicated by the fact that geological forces can cause faulting and tilting of rocks.

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This uses radioactive minerals that occur in rocks and fossils almost like a geological clock.

It’s often much easier to date volcanic rocks than the fossils themselves or the sedimentary rocks they are found in.

Using relative dating the fossil is compared to something for which an age is already known.

For example if you have a fossil trilobite and it was found in the Wheeler Formation.

Ice core sampling normally uses the assumption that the ring bands observed represents years.

One known example where this assumption was used is very misleading.

The relative dating methods themselves are generally sound when used with good assumptions.

However, when scientists apply relative dating to a preconceived uniformitarianism model, the dating methods are only as good as the model.

Estimates of the absolute age of prehistoric and geological events and remains amounted to little more than inspired guesswork, as there was no scientific basis for testing such proposals.”With this background, it is strange that the “standard geologic column” that identifies the rock strata on the earth and assigns very old ages to those strata was developed by Sir Charles Lyell in 1830.

This was done 100 years before absolute dating methods were available.

There are two main methods determining a fossils age, relative dating and absolute dating.

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