Which theory suggests that current geological processes are the same as those that occurred in the past?

The theory that proposes current geological processes are similar to those that occurred in the past is known as uniformitarianism. This concept, introduced by geologist James Hutton in the 18th century and later expanded upon by Charles Lyell, suggests that the same natural laws and processes that operate in the universe now have always operated in the past, and they can explain the geological features we observe today.

Uniformitarianism is foundational to the field of geology as it implies that by studying current geological features and processes, scientists can infer how those features were shaped over time. For example, processes like erosion, sedimentation, and volcanic activity today have been occurring for millions of years, thus allowing researchers to understand the Earth's history.

In contrast, catastrophism focuses on the idea that the Earth has been shaped largely by sudden, short-lived, and violent events, such as meteorite impacts or massive volcanic eruptions. Biogeography deals with the distribution of species and ecosystems in geographic space and time, while natural selection is a key mechanism of evolution, explaining how species adapt over generations. Each of these theories addresses different aspects of biological and geological sciences but does not provide the same direct correlation to the continuity of geological processes as uniformitarianism does.