Radiometric dating methods ppt

08-Jun-2015 17:02

Carbon-14 is a method used for young (less than 50,000 year old) sedimentary rocks.This method relies on the uptake of a naturally occurring radioactive isotope of carbon, carbon-14 by all living things.A commonly used radiometric dating technique relies on the breakdown of potassium (Ar in an igneous rock can tell us the amount of time that has passed since the rock crystallized.

But at the same time, it will be enriched in the elements contained in the later forming minerals, namely sodium and potassium.This belief in long ages for the earth and the existence of life is derived largely from radiometric dating.These long time periods are computed by measuring the ratio of daughter to parent substance in a rock and inferring an age based on this ratio.Since the 1950s, geologists have used radioactive elements as natural "clocks" for determining numerical ages of certain types of rocks. "Forms" means the moment an igneous rock solidifies from magma, a sedimentary rock layer is deposited, or a rock heated by metamorphism cools off.It's this resetting process that gives us the ability to date rocks that formed at different times in earth history.

But at the same time, it will be enriched in the elements contained in the later forming minerals, namely sodium and potassium.This belief in long ages for the earth and the existence of life is derived largely from radiometric dating.These long time periods are computed by measuring the ratio of daughter to parent substance in a rock and inferring an age based on this ratio.Since the 1950s, geologists have used radioactive elements as natural "clocks" for determining numerical ages of certain types of rocks. "Forms" means the moment an igneous rock solidifies from magma, a sedimentary rock layer is deposited, or a rock heated by metamorphism cools off.It's this resetting process that gives us the ability to date rocks that formed at different times in earth history.This age is computed under the assumption that the parent substance (say, uranium) gradually decays to the daughter substance (say, lead), so the higher the ratio of lead to uranium, the older the rock must be.