Firstly: please try not to bring creation/evolution into this. I will award the correct answer to a response which provides links to evidence and sound explanations.
Motivation for the question to follow:
Some of the common mistakes we make in evaluating claims are resisting contrary evidence, looking for confirming evidence, and preferring available evidence. To counteract these tendencies, we need to take deliberate steps to examine critically even our most cherished claims, search for disconfirming evidence as well as confirming, and look beyond evidence that is merely the most striking or memorable. (see link)
Scenario:
I heard about a group of people (yes they happen to be creationists with an agenda, but this should be irrelevant to the question I am posing! ) who obtained some samples of rocks from a lava flow from Mt Ngauruhoe in New Zealand. They claim that the rocks they obtained were from a lava flow which came out of the volcano in 1945. They sent these rocks to 2 labs and had them dated by potassium-argon dating to be between 270, 000 and 1 million years old. (see relevant bits of the link - and please ignore all agenda-based stuff in there! )
My question:
Since the real age of the rocks was around 50 years, does this demonstrate that K-Ar dating is inaccurate? I can think of several possibilities in response to this question:
- K-Ar will never give a lower number than something like 200, 000 years
- They lying about the results
- They sent in the wrong rocks
2 & 3 seem easily falsifiable - anyone else could simply repeat the procedure and see if their results were the same. I haven't heard of this being done, however if you have some evidence to this effect please share it.
The answer to 1 may be what I'm after. I have very little knowledge in the field of radioactive dating, and I'm not even sure if 1 is a true statement. However if it is, then wouldnt this invalidate any results made using K-Ar dating?
Please respond with and flaws in my reasoning or any additional reasons why the experiment was flawed.
edit 1
above i said
They sent these rocks to 2 labs and had them dated by potassium-argon dating to be between 270, 000 and 1 million years old.
which i wrote based on a quick glance of table 1 in the link. however i should have read the article more carefully and written this:
They sent these rocks to 2 labs and had them dated by potassium-argon dating to be either less than 270, 000 years or up to 3.7 million years old.
(the upper limit comes from the 3.5+0.2 figure in table 1). apologies.