Relative dating of rock layers
If you know the relative ages of two rock layers, you know which is older and which is younger.Geologic processes often complicate the dating of geologic layers.Most sedimentary rocks are laid down in flat, horizontal layers.These can later tilt and fold due to tectonic activity, and river cuttings can cause gaps among the layers.Relative dating does not provide actual numerical dates for the rocks.Fossils are important for working out the relative ages of sedimentary rocks.Relative age dating assumes that the lower layers in any particular cross section are.Relative dating simply orders stratigraphic units, or layers of rock, from oldest to youngest.
Correlation can involve matching an undated rock with a dated one at another location.
Correlation with them has helped geologists date many New Zealand rocks, including those containing dinosaurs.
Bring relative dating principles to life with the activity Rock layers and relative dating.
Relative dating is used to arrange geological events, and the rocks they leave behind, in a sequence.
The method of reading the order is called stratigraphy (layers of rock are called strata).