Question

The index fossils have:

• A. Limited geographic distribution and a wide range of time
• B. Limited geographic distribution and a short range of time
• C. Wide geographic distribution and a wide stratigraphic range
• D. Wide geographic distribution and a limited stratigraphic range

Hint:

A good index fossil is widespread geographically but short-lived stratigraphically.

Answer 1

The Correct Option is D

Concept:
Index fossils are used for correlation and relative dating of sedimentary rocks.

Step 1: Geographic distribution.
A good index fossil should be widely distributed geographically so that it can be found in many regions. \[ \text{Index fossil} \Rightarrow \text{wide geographic distribution} \]

Step 2: Time range.
A good index fossil should exist for a short geological time interval. \[ \text{Index fossil} \Rightarrow \text{limited stratigraphic range} \]

Step 3: Final answer.
Therefore, index fossils have wide geographic distribution and limited stratigraphic range. \[ \therefore \text{Correct Answer is (D)} \]