Why is u 238 used for dating rocks
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.
(Of course, as soon as it was the topic of this post, putting Voyager play time in the Dark for the first time ever, the monkey suddenly wanted to do other things and kept clicking away from the page.
But that’s a whole other topic.) So, for all these reasons, it seemed like the right time for a post about names, trends, and the things expecting parents need to think about as they make this decision.
Three years and six friend babies later, I’m 32 and have numbed to the whole thing considerably. (Note: definitely best to keep the name candidates a secret until after the baby’s born—no name will please everyone and other peoples’ opinions really shouldn’t be part of the process for something so personal.
Many are also unaware that Bible-believing Christians are among those actively involved in radiometric dating.
Alpha decay of the The sum of the mass numbers of the products (234 4) is equal to the mass number of the parent nuclide (238), and the sum of the charges on the products (90 2) is equal to the charge on the parent nuclide.
Nuclei can also decay by capturing one of the electrons that surround the nucleus.
The 235U–207Pb cascade has a half-life of 704 million years and the 238U–206Pb cascade is considerably slower, with a half-life of 4.47 billion years.
So when a mineral grain forms (specifically, when it first cools below its trapping temperature), it effectively sets the uranium-lead "clock" to zero.