Rubidium dating rocks the guy your dating seldom calls

26 Apr

However, like caesium, rubidium ions are handled by living organisms in a manner similar to potassium ions, being actively taken up by plants and by animal cells.

Rubidium is a very soft, ductile, silvery-white metal.

German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed method of flame spectroscopy.

Rubidium's compounds have various chemical and electronic applications.

Elemental rubidium is highly reactive, with properties similar to those of other elements in Group 1, such as very rapid oxidation in air.

Rubidium has only one stable isotope, Rb, which composes almost 28% of naturally occurring rubidium, being slightly radioactive with a half-life of 49 billion years—more than three times longer than the estimated age of the universe.

Hence, the Rb/Sr ratio in residual magma may increase over time, resulting in rocks with increasing Rb/Sr ratios with increasing differentiation. Typically, Rb/Sr increases in the order plagioclase, hornblende, K-feldspar, biotite, muscovite.

Radiometric dating of minerals in metamorphic rocks usually indicates the age of the metamorphism.Radiometric dating--the process of determining the age of rocks from the decay of their radioactive elements--has been in widespread use for over half a century.There are over forty such techniques, each using a different radioactive element or a different way of measuring them.The discovery of radioactivity and the radiogenic decay of isotopes in the early part of the 20th century opened the way for dating rocks by an absolute, rather than relative, method.Up to this time estimates of the age of the Earth had been based on assumptions about rates of evolution, rates of deposition, the thermal behaviour of the Earth and the Sun or interpretation of religious scriptures.The Rubidum-strontium dating method, is one of the ways that geologists determine the age of rocks.The utility of the rubidium-strontium isotope system results from the fact that different minerals in a given geologic setting can have distinctly different Sr.For example, consider the case of a simple igneous rock such as a granite that contains several major Sr-bearing minerals including plagioclase feldspar, K-feldspar, hornblende, biotite, and muscovite.If these minerals crystallized from the same silicic melt, each mineral had the same initial Sr as the parent melt.He was employed at Caltech's Division of Geological & Planetary Sciences at the time of writing the first edition.He is presently employed in the Space & Atmospheric Sciences Group at the Los Alamos National Laboratory.