Scientists feel that the earth is 4.55 billion years old but from physical evidence, such as rocks the oldest that they can derive is about 3.8 billion years old. This is because the earth was molten or semi molten for much of its early history.
Some of these rocks are sedimentary, and include minerals which are themselves as old as 4.1 to 4.2 billion years. Rocks of this age are relatively rare, however rocks that are at least 3.5 billion years in age have been found on North America, Greenland, Australia, Africa, and Asia.
The clocks are naturally radioactive elements, called isotopes, such as uranium.
Radioactive elements change spontaneously to non-radioactive elements. For example, radioactive uranium changes, or decays, to non-radioactive lead. If you start with a certain amount of radioactive uranium (100% U) it takes a certain amount of time for one half of the uranium to become lead (50% U,50% Pb). Then it takes the same amount of time for that half to become one half lead (25% U, 75% Pb), and so on. This is called the half-life, or decay constant; it never changes inside rocks.
Different radioactive elements decay at different rates. Some radioactive isotopes have short half-lives, others have very long half-lives, such as millions or billions of years. This is where you need a fancy machine and laboratory to find out how old Earth is; it is done by actually measuring the very tiny amounts of radioactive elements and their decay products, called the parent and daughter, in rocks.
Radiometric dating has a lot of assumptions built into it and there is no real way to test those assumptions.
And if man has been on the earth for as long as secular scientists claim, there would be a lot more people on the earth.
by weblog2 years ago
Anyone can answer if interested...
by qwark23 months ago
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by Emile R3 years ago
I've just been reading about 'out of place' artifacts. Oddities which are dated way, way way outside of the parameters of the currently accepted assumptions on human development on this planet. It appears a lot of these...
by IntuitiveMind6 years ago
How Do You Explain The Age of The Universe?I understand religious people believe God made the world and everything in it and everything in the universe. According to the bible, the world is only several...
by IDONO3 years ago
If the end of the world is inevitable, why not now?Whether it be war, disease, a meteorite, God, or something else we don't know about yet, I think we all believe someday, the Earth will cease to exist. Could be a...
by Anjili5 years ago
Our galaxy will collide with another one in 4 billion years time, says NASA. What do you think?
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