The oldest rock formation identified on Earth is found on the shoreline of Hudson Bay in Canada. This rock formed 4.28 billion years ago. What information does a scientist need to more accurately determine the age of a rock? (1 point)
Responses
The amount of each radioactive element present in the rock.
The amount of each radioactive element present in the rock.
The percentage of each mineral that makes up the rock.
The percentage of each mineral that makes up the rock.
The thickness of younger rock layers that cover the rock.
The thickness of younger rock layers that cover the rock.
The amount of weathering present on the surface of the rock.
The amount of weathering present on the surface of the rock.
Choose one
Both options are correct and equally important in determining the age of a rock.
The first two options are correct:
1. The amount of each radioactive element present in the rock: This is important because radioactive elements decay at a known rate, allowing scientists to use the ratio of parent to daughter isotopes to determine the age of the rock.
2. The percentage of each mineral that makes up the rock: Different minerals have different rates of decay, so knowing the proportions of different minerals in the rock can help determine its age. Additionally, certain minerals are only formed during specific time periods, so their presence can provide clues to the age of the rock.