RE: Researchers were fairly certain that this particular meteor was a member of the primordial solar nebula and chose samples of it for radiometric dating.
OK, here are a few questions:
1) The first major assumption built into radiometric dating is the idea that the parent elements have decayed in the past A THE EXACT SAME RATE as they are decaying today. no one alive today knows what kind of environment existed in the distant past. How do we know how fast elements decayed in the past?
Suppose you come upon a man who is cutting down trees in a forest. You watch him for an entire hour, and he cuts down only 1 tree. Then you count the number of trees he has cut—31 in all. If you assume that he has been cutting trees down at the same rate, then you calculate that he has chopped for 31 hours. However, when you talk to the man, he tells you that, earlier in the day when his ax was sharp and his stomach was full, he was cutting down 5 trees an hour; only in the last hour had he slacked off. With this information, you now understand that he worked for only seven hours, not 31. How do we prove the assumption that the decay rates in the past were the same as they are now?
2) The second assumption is this — We must assume that the daughter element in the sample was not there in the beginning. must assume that the daughter element in the sample was not there in the beginning.
Suppose you go to a swimming pool and find a hose that is pumping water into the pool at a rate of 100 gallons an hour. You discover that the pool has 3,000 gallons of water in it. You calculate that the hose must have been running for 30 hours. However, when you ask the owner of the pool how long she has been running the hose, she tells you that she has been running it for only 1 hour. Most of the water was already in the pool due to a heavy rain the night before. If you assumed that all the water came from the hose, your calculations would be way off—29 hours off to be exact.
I am not saying that these assumptions are wrong in respect to Canyon Diablo meteorites chosen in 1953, but how do you prove that?
You're right about the assumptions. Also, one has to make assumptions about the original concentration of radioisotope being measured, and its original ratio to the decay products.
I can't really prove anything. I was trying to establish the relatively recent origin of the 4.55 Gyr figure.
Figures as from 40 million to 8 billion years has been measured from lunar rock samples, so it's nowhere near an exact science. Hundreds of measurements are taken to see where the trend is.
This might interest you: http://www.scienceagainstevolution.org/v12i9f.htm