Chances are, you learned a simplified version of the technique at one point—if you remember your chemistry teacher discussing isotopes, half-lives, hourglasses, well, that was it—but have since removed the lesson to a box labeled "High School Amnesia" in some dark corner of your brain.

radiometric dating answers-40

Therefore, one can use the measured ratio of potassium to argon in a given mineral to infer the time at which the mineral crystallized and began to accumulate argon (note: 40Ca is not considered in the equation, because it is a common isotope that is already abundant in the rock).

Typically, one assumes that no argon (or negligible amounts thereof) was initially present, because argon is a noble gas and can easily diffuse out of minerals that are still hot.

But whatever your passion for decaying metals and your level of chemical comprehension is now, I want to share my confidence that you can follow along just fine.

Anyone can learn technical jargon (queue Wikipedia page for Potassium Argon Dating); reading this post only requires a knack for scientific reasoning.

I remember reading similar reports years ago, which cited numerous cases of historical lava flows (note: historical meaning humans witnessed it) that were dated radiometrically to be a few hundred thousand to millions of years old.

I was originally quite convinced by the discrepancy that radiometric dating methods were fundamentally flawed: "If radiometric dating methods are so wrong when the age is known, how can we trust them when the age is unknown?When 40K decays radioactively, it produces both 40Ar (argon) and 40Ca (calcium), with a half-life of 1.25 billion years.For example, imagine you crsytallize a rock with 1 gram of 40K (and no 40Ar).Their motivation is obvious: all techniques consistently yield age estimates far older than the purported So where to start?I imagine that I will return to this topic some time in the future, as Ai G has published a number of articles and books that discuss radiometric dating methods (and the Potassium-Argon method in particular).Regardless of the article's technical level, Ai G authors will make all 3 (or 4) points in their publications, so I decided this jargon-free, "short enough to read on your smoke break" commentary on New Zealand volcanoes was a great place to start.