Question

Examine the sample rock outcrops with index fossils that follow and the key that accompanies

the sample


Use the index fossils to determine the proper relative age of the three rock columns.



Please help!!

Answer 1

The relative age of rock layers is determined by examining the index fossils in each layer. The layer with the oldest index fossil is considered the oldest, and the one with the youngest index fossil is the youngest. This is based on the principal of superposition and the use of index fossils.

Step-by-step explanation:

The relative age of rock layers is determined by the concept of superposition, which means that in undisturbed rock formations, the oldest rocks are on the bottom and the layers become progressively younger going towards the top. Index fossils are useful in dating rocks because they represent species that lived for a short period of time but had a wide geographic spread. If two rock layers contain the same index fossils, they are likely to be of the same age.

The process for determining the relative age is as follows:

1. Examine the identified index fossils in each rock layer.
2. Determine the relative age of the index fossils using the provided key.
3. The rock layer containing the oldest index fossil would have the oldest relative age, and thus would be at the bottom of the sequence. The layer with the youngest index fossil would be at the top.

Learn more about Relative Age of Rocks