What two thing must scientists measure to find absoluite age of rock?
To determine the absolute age of a rock, scientists typically measure two key things: the radioactive isotopes present in the rock and the abundance of certain isotopes and their decay products.
First, scientists analyze the rock for radioactive isotopes. Radioactive isotopes, such as carbon-14 or uranium-238, are unstable elements that decay over time, transforming into different elements. By measuring the amount of these radioactive isotopes present in the rock, scientists can calculate how much of the original isotope has decayed and estimate the age of the rock.
Secondly, scientists measure the abundance of specific isotopes and their decay products. Some isotopes found in rocks have stable decay products that accumulate over time. By measuring the ratio of these parent isotopes to their decay products, scientists can determine the length of time it took for the parent isotope to decay and calculate the age of the rock.
These processes, known as radiometric dating methods, provide scientists with valuable tools to determine the absolute age of rocks and fossils. Different isotopes are used for dating different types of materials, depending on their half-life and the age range being investigated.