Which one of the following is not an example of Block Mountain ?

Question

Accepted Answer

The correct answer is Option 4: Caucasus. Here's why:

*   **Why Caucasus is NOT a Block Mountain:** The Caucasus Mountains are primarily a fold mountain range. They were formed by the collision of the Arabian Plate with the Eurasian Plate. This collision caused the Earth's crust to buckle and fold, creating the high peaks and complex geological structures characteristic of fold mountains. While faulting and uplift may have played a secondary role in their formation, the dominant process was folding.

*   **Why the other options ARE Block Mountains:**

*   **Black Forest:** The Black Forest in Germany is a classic example of a block mountain. It was formed by faulting, which caused large blocks of the Earth's crust to be uplifted (horst) and others to subside (graben). The Black Forest represents an uplifted block.

*   **Vosges:** The Vosges Mountains in France are the counterpart to the Black Forest, located on the other side of the Rhine Graben. Like the Black Forest, they are a block mountain range formed by faulting and uplift.

*   **Sierra Nevada:** The Sierra Nevada in California is also a block mountain range. It was formed by faulting along its eastern side, causing the entire block to tilt upwards to the west.

Therefore, because the Caucasus Mountains are primarily a fold mountain range formed by plate collision and folding, and the other options are examples of block mountains formed by faulting and uplift, Option 4 is the correct answer.