In determining the absolute age of two rocks, the most important thing is the radioactive dating of the rocks to compare the radioactive isotopes within them.
Absolute dating involves ascribing numerical age to a rock body. It is usually done by the process of radioactive dating in which the number of daughter to parent isotopes are compared.
This helps to give a precise numerical age to a rock.
Highwall mining is often used when excavating an open-pit mine becomes too expensive. There are many advantages over underground mining, including the fact that it is both more cost-effective and involves less lead time.
Earth spins around its axis, just as a top spins around its spindle. This spinning movement is called Earth's rotation. At the same time that the Earth spins on its axis, it also orbits, or revolves around the Sun. This movement is called revolution.
