Which theory holds that changes in the Earth's crust are the result of continuous and uniform processes?

• A. Evolution
• B. Uniformitarianism
• C. Catastrophism
• D. Plate Tectonics

Answer: (B)

Uniformitarianism is the idea that the Earth's crust changes through the same kinds of forces we see today—like weathering, erosion, sedimentation, and uplift—acting steadily over long periods. Because these processes are continuous and operate in a consistent way, small changes accumulate to create major features like mountains and valleys over time. That fits the description of changes caused by continuous and uniform processes. In contrast, catastrophism emphasizes sudden, dramatic events as the primary shapers of the crust, plate tectonics explains the movement of large crustal plates and the features that result from those movements, and evolution deals with biological change rather than geological processes.