A block mountain is formed as a result of

A block mountain is formed as a result of faulting, specifically a type of fault called a normal fault.
When the Earth's crust experiences stress, it can cause rocks to break along fault lines. In the case of a normal fault, the rocks on one side of the fault move downward relative to the rocks on the other side. This downward movement creates a step-like feature on the Earth's surface, with one side lower than the other. This step-like feature is what we call a block mountain.
As time goes on, the forces of erosion, such as wind, water, and glaciers, start to wear away at the block mountain. However, the harder and more resistant rocks that make up the mountain are less easily eroded compared to the softer surrounding rocks. This causes the block mountain to stand out even more as a prominent and elevated feature in the landscape.
So, to summarize, a block mountain is formed when the Earth's crust experiences faulting, specifically a normal fault. The downward movement of rocks on one side of the fault creates a step-like feature on the Earth's surface, which we call a block mountain. Erosion then works to shape and define the mountain's features over time.