Use the drop-down menus to answer the questions. Which rock layer was the youngest? How do you know that the rock layer is the youngest?

1. The top most layer of rock is the youngest

2. By using Rule of Superposition, one can know which of the rock layer is the youngest.

Explanation:

Based on principle of superposition which explains that in a relative dating and undeformed stratigraphic sequences, the oldest strata is at the bottom of the sequence.

In other words, the stratigraphic dating suggests that the law of superposition is reliable, as an object cannot be older than the materials of which it is composed.

Hence, the oldest sedimentary rock units are considered to be at the bottom, and the youngest are at the top.