Age of Rock Layers: A Journey Through Time

What can we infer about the age of upper rock layers if the lowermost layer is more than 2 million years old?

A. Less than 1 million

B. Greater than 3.5 million

C. Between 2 million and 3 million

D. Between 3 million and 3.5 million

Answer:

If the age of the lowermost layer of a rock sample is more than 2 million years, we can infer that the age of the upper layers would likely be less than 2 million years old. The closest option to this inference from the choices provided is A. Less than 1 million.

Understanding the age of rock layers can give us valuable insights into the geological history of a region. When analyzing rock samples, scientists often use principles of stratigraphy to determine the relative ages of different layers.

If the age of the lowermost layer is more than 2 million years old, it indicates that the rock layers above it are likely younger. This is because in undisturbed rock sequences, the oldest layers are found at the bottom, while the youngest layers are at the top. This concept is known as the Law of Superposition.

Therefore, if the lowermost layer is older than 2 million years, the upper layers would be relatively younger. While the exact age of the upper layers cannot be pinpointed with precision based on this information alone, we can confidently say that they would be less than 2 million years old.

By applying these geological principles, scientists can reconstruct the history of Earth's surface and unveil the fascinating stories hidden within the layers of rock.