Glauconite radiometric dating Chat with webcam girls for free no sign up

However, because the daughter isotopes are a different size they are excluded from the crystal structure.

glauconite radiometric dating-79glauconite radiometric dating-22glauconite radiometric dating-18

This dating method is principally used for determining the age of formation of igneous rocks, including volcanic units that occur within sedimentary strata.

It is also possible to use it on authigenic minerals, such as glauconite, in some sedimentary rocks.

The choice of method of determination of the age of the rock is governed by its age and the abundance of the appropriate elements in minerals.

The samples of rock collected for radiometric dating are generally quite large (several kilograms) to eliminate inhomogeneities in the rock.

As time goes by daughter isotopes are unable to escape the solid crystal.

Thus, radiometric dating of a mineral will yield the time of crystallization. Except under rare circumstance sedimentary rock cannot be radiometrically dated.

It must also be assumed that all the daughter isotope measured in the rock today formed as a result of decay of the parent.

This may not always be the case because addition or loss of isotopes can occur during weathering, diagenesis and metamorphism and this will lead to errors in the calculation of the age.

The only exception to this occurs when the mineral glauconite is present within the rock.

This mineral forms in marine environments as a result of chemical reactions with clay minerals during lithification.

Radiometric dating of minerals in metamorphic rocks usually indicates the age of the metamorphism.

Tags: , ,