Select all the correct answers. Sully works as a geologist in the southwestern United States. He plans to choose an unstable isotope to find the absolute age of a rock sample. Which two aspects must he consider before making his choice? There should be a sufficient amount of the selected isotope in the rock. The isotope should be one that decays at a very fast rate. The hall-life of the isotope must be long enough to capture the age of the rock.

When selecting an unstable isotope for dating rock samples, it’s crucial for Sully to ensure there is a sufficient amount of the isotope present in the rock. If the quantity is too low, the measurements may be unreliable or impossible. This is typically important because a significant amount of the parent isotope will help achieve a more accurate age estimate. Additionally, he must consider the half-life of the isotope he chooses. It needs to be long enough to effectively measure the age of the rock sample. If the half-life is too short, the isotope may have decayed away completely in older rocks, rendering it useless for dating those samples. Choosing an isotope with a suitable half-life is essential for gaining accurate insights into geological timelines!