Zircon age dating Free adult chat no registtaion

07 Feb

Oxygen isotopes and atoms of radioactive uranium trapped in the crystals are, many believe, frozen in time.

Confined as they are in these crystals, many scientists believe that the ratio of parent radioactive uranium to daughter lead atoms in zircons can be used to calculate the ages of the crystals.

For example, as shown at left below, uranium-235 has a half-life of 704 million years.

That means that in 704 million years, one gram of uranium will be reduced to ½ gram of uranium.

The two cascades are different—235U becomes 207Pb and 238U becomes 206Pb.

What makes this fact useful is that they occur at different rates, as expressed in their half-lives (the time it takes for half the atoms to decay).

Both are unstable and radioactive, shedding nuclear particles in a cascade that doesn't stop until they become lead (Pb).We provide examples of complex magmatic zircon from a southern Indian granulite terrane where SHRIMP II and LA-ICP-MS analyses are compared.The SHRIMP data are shown to be more precise and reliable, and we caution against the use of LA-ICP-MS in deciphering the chronology of complex zircons from high-grade terranes.Radioisotopic dating is a key tool for studying the timing of both Earth's and life's history.This suite of techniques allows scientists to figure out the dates that ancient rock strata were laid down — and hence, provides information about geologic processes, as well as evolutionary processes that acted upon the organisms preserved as fossils in interleaved strata.