2007-01-17 08:24:14 · 15 answers · asked by Anonymous in Science & Mathematics ➔ Earth Sciences & Geology
It's based on several things:
1) dating meteorites. When we find a meteorite from this solar system that has a similar composition to earth, you get many young ages, but the oldest and most common date to 4.6 Ga (billion years).
2) isotope trends. When you look at certain radiogenic isotope ratios that change with time, like Rb/Sr or U/Pb, you find that many rocks with differnt ratios of many ages form a line, and the line traces back to an origin of 4.6 Ga as well.
The oldest life is 3 1/2 Ga, the oldest rock is about 4 Ga, and the oldest date ever found is on the highly durable mineral Zircon from Australia, it's date is 4.2 Ga. So, there is no direct method, it is based on inferences. However, many different inferences lead to the same number 4.559 Ga (to be specific).
You would have to throw out everything we know and love about Geology to accept a young earth view. When you look at the Grand Canyon, how can you say that only took 6000 years to form?
2007-01-17 14:26:02 · answer #1 · answered by QFL 24-7 6 · 2⤊ 0⤋
4,500 million (4.5 billion) years is a fair estimate.
BEWARE: Young Earth Creationists will always muscle in on this sort of question and insist that this is all some sort of scientific conspiracy. Trust me - as a practising geologist,these arguments are all without foundation (either that or oh dear I'm destined to burn in hell for an eternity!).
To refute two claims selected at random (I don't have the time to discuss all of them):
(1) C14 is found in Coal. Coal is highly microporous (like charcoal) and easily adsorbs atmospheric CO2, when mined or exposed at the surface. So C14 would be expected. The method when applied to coal is simply highly susceptible to contamination.
(2) old radiometric dates are produced from deposits resulting from the Mount St Helens volcanic eruption (>therefore one cannot rely on radiometric dating). Well of course - nearly all of the volcanic products were not fresh lava, but were pulverized remains of earlier volcanic material (ash & dust) and crustal material ripped out from the underlying strata when the volcano blew. So one would naturally expect a huge range of dates, many of them very old! You have to be very careful what you sample!
2007-01-18 04:35:09 · answer #2 · answered by grpr1964 4 · 1⤊ 0⤋
To be exact... 4.7 billion years, 294 days, 14 minutes and 12, no 13 seconds ago. Strangely enough, tommorrow is the Earths Birthday.
Hope it helps you out
2007-01-17 17:03:28 · answer #3 · answered by pop c 2 · 0⤊ 0⤋
Widely accepted scientific evidence indicates that the Earth was formed around 4.57 billion years ago.
You could get more information from the link below...
2007-01-18 05:22:18 · answer #4 · answered by catzpaw 6 · 0⤊ 0⤋
about 4 Billion years old.
2007-01-17 16:32:28 · answer #5 · answered by daddyspanksalot 5 · 0⤊ 0⤋
Experts say over 4 billion.
2007-01-21 16:11:01 · answer #6 · answered by Ollie 7 · 0⤊ 0⤋
Approximately 4.5 billion years.
2007-01-17 16:27:51 · answer #7 · answered by cigaro19 5 · 0⤊ 0⤋
Depends how many decimal places you want and how precise measurements are:
Current "best guess" is about: 4.567 billion years old; see:
http://en.wikipedia.org/wiki/Age_of_the_Earth
2007-01-17 16:30:25 · answer #8 · answered by Anonymous · 0⤊ 0⤋
No one on earth knows the answer to your question.Most of the so called scientific test are nothing more that guess work.
2007-01-17 20:47:21 · answer #9 · answered by Anonymous · 0⤊ 2⤋
It was formed around 4.6 billion years ago.
2007-01-17 16:36:28 · answer #10 · answered by Toby 2 · 0⤊ 0⤋