Question

read the passage and answer the following question(s).
fossils in rock strata
scientists are investigating rock formations at two different locations. the scientists find different fossils in the layers at each location. the scientists have labeled each rock layer with a letter. the rock layers are shown.
how does layer a compare to layer g?
a. layer a and layer g are the oldest layers in their locations
b. layer a is older than layer g
c. layer a is younger than layer g
d. layer a and layer g are the youngest layers in their locations

Explanation:

In geology, the principle of superposition states that in undisturbed sedimentary rock layers, the lower layers are older than the upper layers. In Location A, Layer A is at the bottom, so it is the oldest layer in Location A. In Location B, Layer G is not at the bottom (Layer F is below Layer G), so Layer G is not the oldest in Location B. Also, since Layer A is at the bottom of its location (oldest there) and Layer G is above Layer F (so younger than Layer F in its location), and comparing their positions in the strata - based on the superposition principle.

Answer:

B. Layer A is older than Layer G