Rb sr dating
Strontium-89 is employed in the treatment of bone cancer, as it targets bone tissues, delivers its beta radiation, and then decays in a few months’ time (half-life 51 days).
Although early stratigraphers could determine the relative order of rock units and fossils, they could only estimate the lengths of time involved by observing the rates of present geologic processes and comparing the rocks produced by those processes with those preserved in the stratigraphic record.
The abundance and variety of fossils in Phanerozoic rocks have allowed geologists to decipher in considerable detail the past 600 million years or so of the Earth’s history.
In Precambrian rocks, however, fossils are rare; thus, the geologic record of this important part of the Earth’s history has been especially difficult to decipher.
The metal was isolated (1808) by Sir Humphry Davy, who electrolyzed a mixture of the moist hydroxide or chloride with mercuric oxide, using a mercury cathode, and then evaporated the mercury from the resultant amalgam. Strontium may be obtained in the form of sticks by the contact cathode method of electrolysis, in which a cooled iron rod, acting as a cathode, just touches the surface of a fused mixture of potassium and strontium chlorides and is raised as the strontium solidifies on it.
Metallic strontium may be also obtained by reduction of the oxide with aluminum.
This variation is used in dating geological samples and in identifying the provenance of skeletons and clay artifacts.