everyday i see the documentries and scientists tell the age of things in thousands of years how can they guess that. is there any accurate method of that or just guessing.
2006-06-06 11:35:15 · 9 answers · asked by Anonymous in Science & Mathematics ➔ Earth Sciences & Geology
they guess!!!???
2006-06-06 11:38:23 · answer #1 · answered by amylinehan14 2 · 0⤊ 0⤋
Radioisotope dating, as corvis_9 explained. I would add that for trees and wood, the growth rings can often be used to help place a date. Even if the tree is long dead, they can often match the pattern of the growth rings to major climate events. A major volcanic ashfall would leave its mark on the growth patterns of all the trees in a given area, and might be identifiable from historical records. These sorts of things also go into calibrating the carbon dating process.
2006-06-06 20:30:04 · answer #2 · answered by injanier 7 · 0⤊ 0⤋
Radioisotope decay. Yes it is accurate, in spite of creationist claims to the contrary, The half-lives of radioisotopes can be predicted from first principles through quantum mechanics. Any variation would have to come from changes to fundamental constants.
The 'half life' is the time it would take for half of the sample to decay into something else. Half life is calculated by measuring the amount and type of radiation produced by a given sample size in a set period of time. The radiation is produced by the decay of unstable isotopes. The radiation produced by natural decay does not induce accelerated decay in normal concentrations.
Carbon-14's half life is 5,700 years, it's reliable for dating objects up to about 60,000 years old, after that the amount of carbon-14 in the sample would be so low as to be within the sampling error margin putting the age at +60,000 years minimum.
Potassium-40 is another radioisotope found in living things
it's half-life is 1.3 billion years.
Some other radioisotopes
Uranium -235 half-life = 704 million years
Uranium -238 half-life = 4.5 billion years
Thorium-232 half-life = 14 billion years
Rubidium-87 half-life = 49 billion years
2006-06-06 19:47:32 · answer #3 · answered by corvis_9 5 · 0⤊ 0⤋
it's all guessing. Carbon dating is not acurate at all. It's based on an assumption that carbon depletes at the same rate in everything and also at a steady rate. Not true.
2006-06-06 18:40:19 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Its called Carbon-Dating.
2006-06-06 18:38:14 · answer #5 · answered by fscarberry20 3 · 0⤊ 0⤋
currently the new process of chlorine dating it much more accurate. since carbon can be accelerated.
2006-06-13 17:39:55 · answer #6 · answered by Jase Mighty Pirate 3 · 0⤊ 0⤋
This topic was covered accurately enough, I wont bore you with more data
2006-06-13 11:51:05 · answer #7 · answered by Opus 3 · 0⤊ 0⤋
they measure the amount of radioactive elements in the fossil.
2006-06-06 22:42:52 · answer #8 · answered by That one guy 6 · 0⤊ 0⤋
don't know
2006-06-06 19:31:54 · answer #9 · answered by Annie Mae 3 · 0⤊ 0⤋