Dating of zircons dating after death of spouse with children
If the rim is wider than 5 microns a precise age can be measured.
Moreover, even if the rim is not preserved, and the core not encountered, the Pb loss zone if wide enough (~15 mcirons) can be used to construct a discordia on that single grain with moderately precise lower and upper intercept ages.
Now since all rocks are somewhat porous, and since we are pretty much obliged to date rocks from near the surface, it's hard to find instances in which uranium has not been lost.
For this reason we expect zircons, when formed, to contain some uranium, but virtually no lead.
Using the rim-piercing technique gives us indication of the Himalayan event in about 5 to 10 percent of all analysed grains.
In 60 seconds, a metamorphic rim, Pb loss region, and inherited core can be analysed.
This will not only limit the progression of research, but potentially stifle Australia’s ability to compete with the world in the field of palaeontology.
The Winton Formation is one of the only places on the planet that preserves fossils from before, during and after the break-up of a supercontinent. Palaeontologists need to start using all the dating techniques available to them, to ensure valuable sites like the Winton Formation are given the scientific consideration they deserve.