Question
How many dating systems like carbon dating are there and what age ranges are they suitable for?
Answer
There's quite a few, all of which are types of radioactive dating. They include potassium-argon dating, that's useful for rocks over 100,000 years old. There's also uranium-lead dating, which has an age range of 1-4.5 million years old. It can be used for such long time spans because the half-life of uranium turning into lead is billions of years, in the order of the age of the Earth at 4.5 billion years.
Mike, from Cambridge, also called in to remind us about thermo-luminescence which can be used in pottery, also obsidian hydration and uranium trail dating when you observe the trails left behind by uranium decomposition.
Comments
Dating rock on planets.
I am extremely interested in pre- history on Earth and other civilizations that have visited Earth during the last few millennia . Why is it that as scientists we can`t seem to tie down better dates when we talk about millions and/or billions of years. I am very surprised that we use moss and lichens these days : such a crude way to date anything. In the field it is useful but I would expect a much more accurate result in a laboratory setting.
I realise that carbon dating is often out of the question and we are looking at Potassium or Uranium for half-lives. Are we struggling with this or is it a matter of time or even another dating progress using light for example.
Add a comment