If both the moon and Earth formed at the same time,why have no 4.6 billion year old rocks been found on Earth?

Answer 1

great question, asking things like that is exactly what science is all about!

The best theory which has resulted from analysing rock samples from the moon suggests that early in the solar system's history, a body roughly the size of Mars collided with the Earth. The resulting debris accreted to form both the Earth and the Moon. The Earth is much larger than the moon, The pressure and radioactivity within the Earth keep it hot and molten. Convection currents in the molten Earth drive the thin crust in what we call plate tectonics. This is the theory that the Earth's crust is a thin shell comprising a series of broken plates that rub against each other. At the boundaries of some plates, one piece of crust will be forced beneath another. Throughout the history of the planet, much of the ancient crust has been consumed at such plate boundaries. New crust is being formed even today at places like the mid-atlantic spreading ridge. This is why there are not many craters left on Earth. Some areas including parts of Africa, Canada, and Australia have been dated to be the oldest surviving crust on the planet. Some Zircon (a very hardy mineral) grains from Australia have been dated from their radioactive parent and daughter isotope ratios to be 4.4 billion years old! the moon's crust is too rigid to have plate tectonics, hence its original crust has survived. It is thought that Mars used to have active plate tectonics. Half of mars is relatively free of impact craters and is believed to represent younger crust than the older more rigid side.

Answer 2

The moon has existed in a sterile atmosphere for the previous 4.6 billion years, provide-or-take a week or so. IE no climate erosion or something like that. the situation in basic terms bakes interior the sunlight for 2 weeks and large freezes with the aid of a 2 week nighttime with an occasional impact from a meteor. different than that the moon is a quite boring place. Ask Neil Armstrong, he spent a weekend there as quickly as. The Earth on the different hand is a swinging place. each and all the time recycling itself. previous rocks get floor into sand and swallowed up in fissures and get spit back out returned as lava.

Answer 3

Why? The record is very incomplete, and becomes more incomplete with time due to erotion and tectonics.

Earth's age is inferred 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?

Answer 4

The earth and the moon were both entirely molten at first. The oldest solid rock crystals appear to have solidified about 4,000,000,000 (4 billion) years ago. The moon was molten at about the same time. There is nothing in the relationship between the earth and the moon that would limit the solidification times of either body. That part of your question is not clear.

Try internet searches on "petrology" and "oldest rock." Or visit the library.

Answer 5

where did you hear that at? i think technically the moon formed much later after the earth did.

its been a while but from what i remember the the moon was once an asteroid or a comet of some sort, and it hit the earth which then nocked it off its axis and caused all sorts of problems like ice melting and freezing in different areas, and the earth now has seasons because of this, and i think there's north and "true north".
anyway after the collision the left over material from the impact was caught in the gravitational pull of the earth and began to circle where it is now, although not perfect because eventually it will crash back into earth.

in more severe cases it would be blown up so badly that it would end up like a ring around saturn.

Answer 6

The moon was not formed with the earth.... When the earth was young, a large asteroid collided with the earth, destroying the earth.... the remaining debris (both of the earth and the asteroid) then reformed both the earth and the moon and they came back together.