some line a’-b’-c’ (Figure 2), whose slope will

Determining the numerical age of rocks and fossils

for methods to quantify the age of the Earth. Lord Kelvin and

whereas the Sr isotopic composition (87Sr/86Sr ratio) doesn’t. The two ages

(34). These authors studied dikes of basalt that intruded

Using paleomagnetism to date rocks and fossils

independently discovered that the glassy margins of submarine

Radiometric age dating

most common interpretation is that it signifies the age of the

Sciencing_icons_atomic & molecular construction atomic & molecular structure

isochron diagram (Figure 2). The 87Rb and 87Sr

of carbon equilibrium. Evidence for the interval of accelerated decay is found in zircon

Sciencing_icons_electronics electronics

example, within the rubidium-strontium technique one compares rubidium-87/strontium-86