fossils: Relative dating techniques

Relative Dating

A method used to determine whether a fossil or artifact is older or younger than another based on its relative position, without determining its actual numerical age.

Fluorine Analysis

A relative dating technique that compares the amount of fluorine absorbed by fossilized bones from surrounding groundwater, where older bones contain higher fluorine levels.

Fluorine Analysis Limitation

This relative dating method can only compare fossils found within the same local area, as groundwater fluorine concentrations vary by location.

Stratigraphy

The study of rock layers (strata) and sedimentation to determine the relative chronological sequence of geological events and fossils.

Sedimentation

The geological process by which materials such as clay, silt, and rock fragments settle into layers over time.

Principle of Superposition

The geological rule stating that in undisturbed rock layers, the uppermost strata are younger than the strata lying beneath them.

Stratigraphic Distortion

Alterations to rock layers caused by Earth's crustal movements, which can disrupt or invert the original sequence of strata.

Correlation of Rock Strata

The process of matching and comparing rock layers from different geographical areas using rock types or contained fossils.

Index Fossils

Widely distributed fossils of organisms that existed on Earth for only a short geological time period, used to correlate rock layers and increase relative dating accuracy.